SELF REGULATORY DEPLETION EFFECTS ON SPEED WITHIN
A COMPLEX SPEECH PROCESSING TASK
Angela Reif
A Thesis
Submitted to the Graduate College of Bowling Green
State University in partial fulfillment of
the requirements for the degree of
MASTER OF SCIENCE
August 2014
Committee:
Miriam Krause, Advisor
Alexander Goberman, Committee Member
Ronald Scherer, Committee Member
© 2014
Angela Reif
All Rights Reserved
iii
ABSTRACT
Miriam Krause, Advisor
Past research has supported the idea that self-regulation uses a limited resource which is
subject to depletion (Hagger, Wood, Stiff, & Chatzisarantis, 2010). Depletion has generally been
measured by the reduced accuracy of task performance on one executive function task that
follows another executive function task. The current study used two measures of time within a
speech processing task to explore the effects of depletion on complex speech processing. Half of
the participants completed the speech processing task before an inhibitory writing task (Group
A), and the other half of the participants completed the inhibitory writing task before the speech
processing task (Group B); Group B was therefore predicted to be depleted in their ability to
complete the speech processing task relative to Group A. During the speech processing task,
participants listened to sentences from two different speakers simultaneously, one a native
speaker of English and the other a non-native speaker of English. Listeners were visually cued to
listen to and repeat one speaker or the other in a random sequence. After repeating each sentence,
participants were given a forced choice question requiring them to identify the sentence spoken
by the target speaker. The forced choice answer set provided two answer choices, the sentence
spoken by the native speaker of English and the sentence spoken by the non-native accented
speaker of English. Answers to these forced choice questions were used to verify whether
participants had attended to the correct target. The current study analyzed response times for the
forced choice questions (FCR) as well as the self-paced advancement (SPA) times (the times the
participants waited before progressing from item to item). Times were analyzed for each
participant and as means across participants between the two experimental groups. Results
iv
indicated no significant group differences for either forced choice response (FCR) times or selfpaced advancement (SPA) times. Regression analyses revealed a trend of decreasing SPA time
over the course of the experiment but no trends were observed for FCR time. These results
indicate a lack of depletion effects on measures of FCR and SPA time and the possible effect of
increasing automaticity on the SPA time measure.
Keywords: depletion, self-regulation, speech processing, processing speed
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ACKNOWLEDGMENTS
I would like to express my gratitude to my advisor, Dr. Miriam Krause, for all of her
guidance in helping me in the process of conducting this thesis project. You have been a
wonderful mentor to me and have allowed me to grow immensely in my understanding of
executing, analyzing, and writing findings for a research project. Your help was invaluable to
me, and I am extremely thankful for your direction and encouragement throughout my thesis
project. I really enjoyed learning from you during this experience and appreciated the quality of
your feedback and considerable commitment in helping me to succeed.
I would also like to thank my committee members, Dr. Alexander Goberman and Dr.
Ronald Scherer, for agreeing to be on my committee. I greatly appreciated your beneficial advice
and suggestions. You both have inspired me immensely to conduct research and have helped me
to improve my ability to evaluate and engage in research.
I would especially like to thank Mr. Jason Whitfield for his help in collecting data and
answering questions I have encountered along the way. Your help has really increased my
understanding of research methods and statistics.
Lastly, I would like to thank my husband, Jeff, and my family and friends for their
support! I owe a great deal to them, especially my husband, and my sister, Chriss, for her belief
in me.
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TABLE OF CONTENTS
Page
INTRODUCTION .....……....................................................................................................
1
Executive Function/ Self-Regulation ........................................................................
1
Self-Regulation Depletion Theory ............................................................................
2
Decision Making ..........................................................................................
3
Emotional Regulation ..................................................................................
4
Attention ......................................................................................................
6
Alternating Attention and Switch Costs ......................................................
6
SR Depletion with respect to Fatigue, Motivation, and Affect ................................
7
Fatigue ...........................................................................................................
7
Motivation .....................................................................................................
8
Affect ............................................................................................................
9
Recovery from Self-regulatory Depletion ................................................................
10
Speech Processing and Working Memory .................................................................
11
Processing Speed ......................................................................................................
12
METHODOLOGY
...........................................................................................................
16
Participants
...........................................................................................................
16
Structure of overall study ..........................................................................................
18
Speech Processing task .............................................................................................
18
Stimuli ...........................................................................................................
19
Instruction Phase ...........................................................................................
20
Familiarization Phase ....................................................................................
20
vii
Training Phase ..............................................................................................
20
Assessment Phase .........................................................................................
21
Experimental Phase .......................................................................................
22
Inhibitory Writing Task ............................................................................................
23
Standardized Testing .................................................................................................
24
Data Analysis ............................................................................................................
24
RESULTS
............................................................................................................
27
Forced Choice Response Time ................................................................................
27
Overall Group Effects ....................................................................................
27
Group Effects Considering Trial ...................................................................
28
Group Effects Considering Trial and Speaker ..............................................
28
Within-Participant Trends .............................................................................
30
Switch Costs...................................................................................................
32
Self-Paced Advancement Time .................................................................................
32
Overall Group Effects ...................................................................................
32
Group Effects Considering Trial ...................................................................
33
Group Effects Considering Trial and Speaker ..............................................
34
Within-Participant Trends .............................................................................
34
Significance of Within-Participant Trends ...................................................
36
Switch Costs...................................................................................................
36
............................................................................................................
38
Forced Choice Response Time ..................................................................................
38
Self-Paced Advancement Time..................................................................................
41
DISCUSSION
viii
Target Speaker Effects ...............................................................................................
43
Switch Costs ............................................................................................................
44
Limitations and Future Directions .............................................................................
45
CONCLUSIONS
………………………………............................................................
48
REFERENCES
……………………............................................................................
49
APPENDIX A. Participant Means and Standard Deviations................................................
54
APPENDIX B. Regression Graphs .......................................................................................
55
APPENDIX C. Outliers ........................................................................................................
59
APPENDIX D. HSRB Approval ..........................................................................................
70
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LIST OF TABLES
Table
Page
1
Participant Characteristics .........................................................................................
17
2
FCR Regression Results ................................................................................………
31
3
SPA Regression Results.................................................................................………
36
x
LIST OF FIGURES
Figure
Page
1
Non-native speaker cue ..............................................................................................
21
2
Native speaker cue .....................................................................................................
21
3
Quiz Screen
………………………………………………………………………
22
4
Effort Rating …………………………………………………………………….…
23
5
FCR Times by Group .....................................................................................………
27
6
FCR Times for Native-accented Speaker ......................................................………
29
7
FCR Times for Non-native-accented Speaker ...............................................………
29
8
Representative Slope –Participant A4 ...........................................................………
31
9
SPA Times by Group .....................................................................................………
33
10
SPA Time Over Trial .....................................................................................………
34
11
Representative Slope –Participant B4........................................................................
35
1
INTRODUCTION
The current study examined whether two different measures of speed in a speech
processing task, forced choice response times (FCR times) and self-paced advancement times
(SPA times), were sensitive to self- regulatory depletion in a group of healthy adult participants.
For the purposes of the current study, self-paced advancement times (SPA times) are defined as
the self-paced time the participants waited before progressing from one item to the next. Forced
choice response times (FCR times) are defined as the amount of time the participants took to
answer a two-option multiple choice question of which target speaker they had just attempted to
repeat. These measures of speed are of interest because processing speed is often impaired in
certain populations, including people with traumatic brain injury (TBI). The analysis of selfregulatory depletion effects in the current pilot group of healthy participants can later be used for
comparison with people with TBI in a future study.
Executive Function/Self Regulation
In neurocognitive contexts, self-regulation is often studied in terms of “executive
functions” or executive control. According to Miyake, Friedman, Emerson, Witzki, Howerter,
and Wager (2000), executive functions include “shifting of mental sets, monitoring and updating
of working memory representations, and inhibition of prepotent responses” (p. 50). These
functions can also be conceptualized as higher level cognitive processes used in inhibition,
planning, and organization, which can become impaired with damage to the frontal lobe
(Sohlberg & Mateer, 2001). These processes of inhibition, planning, and organization are
important for every-day tasks. A breakdown in these processes significantly affects one’s life, for
example, causing difficulty with meeting requirements at work or school or with completing
family obligations.
2
One model used for studying executive functions is Baddeley’s (1986) framework for
working memory. This model includes three parts: the phonological loop, involved in processing
of speech information; the visuospatial sketchpad, involved in processing visual and spatial
information; and the system that controls these two components, the central executive. This
model broadly attributes control of information to a unitary system of executive function. More
simply stated, this unitary system or central executive is the system responsible for controlling
one’s response to visual, spatial, and/or speech input from the visuospatial sketchpad and
phonological loop.
According to Baddeley (2012), a strength of the phonological loop component of
working memory is that is allows for temporary storage while requiring little attention. While
minimal attention is needed to store speech information in working memory, the addition of
input stimuli in the current experiment which participants will need to inhibit may require higher
level attention processes under the control of the central executive. The complex speech
processing task used in the current study is projected to require the use of the central executive
because it requires components of focused, selective and alternating attention as well as
supervisory control of attention (e.g. Mathias & Wheaton, 2007). These higher levels of attention
are utilized in the experiment because participants never know which of the two speakers will be
the target for the upcoming trial, and must attend to the visual cue and then identify and attend to
the target speaker while ignoring the distracting speaker.
Self-Regulation Depletion Theory
The theory that self-regulation relies on a limited resource is well supported in the
literature (Baumeister, Muraven, & Tice, 2000; Hagger et al., 2010 meta-analysis; Schmeichel,
2007; Vohs, Baumeister, Schmeichel, Twenge, Nelson, & Tice, 2008). When this resource is
3
expended, subsequent acts of executive control become impaired. This state when executive
function becomes impaired is called self-regulatory (SR) depletion, ego-depletion, or simply
depletion. Past research has found SR depletion effects in executive functioning tasks across
multiple domains including decision-making, emotional regulation, and attention.
Most depletion studies are structured using a sequential dual task paradigm in which the
first task is a self-regulatory activity for one group of participants and a non-self-regulatory
version of the same activity for the second group. The second task is a different self-regulatory
activity performed by participants in both groups. The two groups are then compared on their
ability to self-regulate during the second task. To measure depletion effects on the second task,
researchers have used various measures including task accuracy, persistence, or inhibition.
Decision Making. Decision making is one domain of self-regulation that has been
indicated in depletion effects. Vohs et al. (2008) conducted experiments to determine the effects
of decision-making on subsequent self-regulatory ability. In their first two experiments,
participants in the experimental group were asked to make decisions between products, (e.g.
Would you prefer product A, a red t-shirt, or product D, a black t-shirt?), while participants in
the control group merely gave their thoughts and opinions about advertisements. Participants’ SR
ability was then assessed. In the first experiment, SR ability was tested by how much of a badtasting beverage participants could consume. In the second experiment, participants’ SR ability
was measured by how long participants could keep their arms in cold water. In experiments 3
and 4, participants in the experimental condition were asked to decide which classes they would
take, given choices about courses to satisfy degree requirements. SR ability was then measured
by how long they studied for an upcoming math test (experiment 3) or persisted on unsolvable
tracing puzzles (experiment 4). The researchers’ findings indicated that making choices reduced
4
participants’ ability to persist on subsequent tasks of self-regulation compared to the control
group who did not make decisions. Additionally, the researchers in this study performed
experimental manipulations examining the effects of amount and pleasantness of decisions on
SR ability. Participants were randomly assigned to three experimental conditions: a control
group, a short choice group and a long choice group. Before the experiment, participants were
asked to rate their level of enjoyment and past experiences with completing wedding gift
registries. The short choice group then completed a gift registry online for four minutes, and the
long choice group completed the registry for twelve minutes. The control group was instructed to
simply think about the route that they would take to get home. After the first task, depletion was
measured by the amount of time participants passively watched a rigged video tape that showed
mostly static and faint images of people talking. The participants were told that they would be
given questions about the video after viewing it. The results of these manipulations indicated that
making a large number of choices was depleting regardless of how pleasant the choices were
considered by participants.
Emotional Regulation. In addition to active behaviors like decision making, research on
depletion has also found depletion effects related to emotional regulation. Schmeichel (2007)
performed four experiments testing ego-depletion in a variety of modalities (visual, written, and
emotional self-regulation). In all four experiments, depleted participants performed significantly
more poorly on the second task requiring executive function than undepleted controls whose first
tasks did not involve self-regulation. Two of the four experiments they conducted (Experiment 3
and Experiment 4) used tasks involving emotional-regulation. In Experiment 3, participants in
the experimental condition completed taxing, working memory tasks in which they would solve
a math equation, indicate if the answer given was correct, then would be given an individual
5
word to recall later. Participants in two other conditions (the non-self-regulatory task versions)
either recalled a pair of two words immediately after the words were presented or recalled a sixword set, immediately after they were presented before completing the math equations as a
separate task. In the second task, all participants were instructed to inhibit their responses to
emotionally-charged films. The participants in the working memory condition with mixed
equation-word stimuli were significantly less able to inhibit their emotional responses to the film,
indicating the effect of depletion on emotional-regulation.
In the fourth experiment, participants performed an emotional-regulation task first, in
which they were instructed to exaggerate their emotions before completing an operation span
task similar to the working memory task for experiment three. Results of this experiment found
that participants who had exaggerated their emotions performed significantly worse on the
working memory task. These findings suggest that regulating emotions was also depleting
causing poorer performance on the subsequent self-regulation task.
Baumeister, Bratslavaky, Muraven, and Tice (1998) also investigated the effects of
depletion using an emotional-regulation task. In one of the four experiments examining depletion
in this study, participants in the experimental group were instructed to try not to show any
emotion while watching a movie and were then assessed on the number of words they could
unscramble (anagram performance) in a six-minute time period. Meanwhile, participants in the
control condition were instructed to allow their emotions to “flow” while watching a movie
before they completed the anagram task. Results of this experiment revealed that participants in
the suppress-emotion condition performed significantly worse in the number of anagrams they
solved correctly.
6
Attention. The domain of attention in self-regulation depletion has also been studied.
Schmeichel (2007) found that after completing a selective attention task, participants exhibited
depletion effects on a subsequent task of working memory. Depletion effects were demonstrated
by poorer performance on the working memory test after completing the selective attention task.
The depleting task required participants to pay attention to certain information displayed on a
television screen, while ignoring other distracting information on the screen. Whereas in the nondepleting version of the attention task, participants were not given any instructions about which
information to which they should attend. Working memory performance was measured as
described above. Participants were presented with math equation-word pairs in a two, three, four,
or five-pair set before they were asked to recall the target words.
The current study uses a speech-processing task that requires supervisory control of both
selective and alternating attention. Participants have to selectively attend to a target speaker
while ignoring a second, non-target speaker, and in addition must alternate their attention
between a native speaker and non-native speaker in an unpredictable pattern. The random – and
therefore unpredictable – target for selective attention requires participants to regulate their
attention to the target stimulus and inhibit their attention to the non-target stimulus.
Alternating Attention and Switch Costs. This use of alternating attention in the current
experiment could influence the time measures that were used as dependent variables. While
studies of depletion using attention tasks have used inhibition of attention over a substantial
period of time, such as ignoring certain text on a television screen (Schmeichel, 2007), time
measures of trials involving switching or alternating attention have not been used in depletion
studies. In response time research, the use of alternating attention has resulted in switch costs in
which responses on blocked trials that require switching take longer than responses on blocked
7
trials which do not require switching (Gopher, Armony, and Greenshpan, 2000). In the present
experiment, it is possible that the existence of switch costs could account for decreases in
participants’ speed for trials that require switching attention to a different stimulus. The current
experimental task required participants to alternate attention in an unpredictable pattern from one
target speaker to the other. Therefore, trials that require switching may show increases in the
amount of time participants take to answer the forced choice questions or progress to the next
item when compared to trials when the target remains the same as the previous item.
SR Depletion with respect to Fatigue, Motivation, and Affect
Because depletion occurs with acts of self-regulation, variables of fatigue, motivation,
and affect have been studied due to their possible effect on acts of self-control.
Fatigue. Fatigue is one alternative explanation that has been proposed for SR depletion
effects, and research has shown that depletion often corresponds with, but cannot be completely
explained by, reported feelings of fatigue (Baumeister, Bratslavsky, Muraven & Tice, 1998;
Hagger, Wood, Stiff, & Chatzisarantis, 2010). When one exerts effort used in self-regulatory
tasks, a generalized response of subjective fatigue and reduced task performance is evoked;
however, in their meta-analysis Hagger et al. (2010) suggest that fatigue acts as a mediator of
effects of resource depletion on later tasks, in that executive control requires effort which can
lead to fatigue and result in reduced ability for self-regulation. They also suggest that fatigue
could also act as an indicator to motivate people to conserve their resources when depleted, as
indicated in a study by Muraven, Shmueli, and Burkley (2006) in which researchers found that
participants did seem to conserve resources of self-control when they anticipated the required use
of self-control for a subsequent task.
8
In the current study, effects of fatigue were not explicitly examined, but may have played
a role in the measure of forced choice response time (FCR time) or self-paced advancement time
(SPA time). For example, participants affected by fatigue could be predicted to take longer to
move on to the next item (longer SPA time) or to move more quickly to the next item (shorter
SPA time) in an effort to conserve resources. However, the writing inhibition task takes only six
minutes and the speech processing task takes approximately half an hour, so fatigue was not
expected to be a strong factor in this study.
Motivation. Another alternative explanation which has been suggested for depletion
effects is decreased motivation. This view is consistent with the strength model of selfregulation: as individuals engage in tasks requiring self-regulation, they may begin to view the
goal of a later task as less important due to the costly demands of completing the task. The result
of viewing the task goal as unimportant will be reduced motivation to complete the task well
(Hagger, et al., 2010). On the other hand, given adequate motivation, participants can overcome
effects of mental fatigue (Boksem, Meijman, & Lorist, 2006). Muraven and Baumeister (2000)
proposed the idea that self-regulation tasks may cause only partial depletion, leaving some
resources for further tasks if the motivation or incentive is high. Ultimately, though, once the
ability for self-control becomes impaired enough through depletion, an individual will have some
decrease in ability to further regulate the self even if motivation is high (Baumeister, Vohs, &
Tice, 2007). In the current study, motivation was expected to be roughly equivalent among
participants, since the task required little personal or emotional engagement, and all participants
were offered the same compensation regardless of their performance.
A more recent explanation of the interaction between motivation and depletion has been
posited by Inzlicht, Schmeichel, and Macrae (2014). Their process model of self control
9
depletion suggests that motivation moderates depletion without being limited by finite selfregulatory resources. In their view, the brain performs optimally when it can alternate between
“have to” and “want to” activities. Thus when an individual persists too long with tasks that
require self-regulation (“have to”), they have suboptimal performance. While this model
provides a different explanation for depletion effects, it does not dispute that depletion occurs;
rather, it suggests that depletion is not due to a limited resource, as has been the widely held
explanation. If this model is correct, depleted participants would still perform less accurately (or
in the case of the present experiment, act more slowly); however, according to this model, this
would be due to a decrease in desire to perform what they “have to” do for the experiment as
opposed to reaching the limit of a finite self-regulatory resource. While Inzlicht, Schmeichel, and
Macrae provide this alternative explanation for depletion, they do not question its occurrence: for
the purposes of the current study, the underlying mechanism responsible for depletion is not of
primary concern or tested by the experiment.
Affect. Another possible variable affecting performance ability attributed to depletion is
emotional affect. Tasks requiring self-control can be taxing and frustrating for participants and
cause negative emotions (Ciarocco, Sommer, & Baumeister, 2001). In order to monitor whether
negative affect may be a factor affecting ego-depletion, the current study used the Self
Assessment Manikin Scale (SAM) (Lang, 1980; Hodes, Cook, & Lang, 1985) to monitor
participants’ moods as the study progressed. While a direct relationship between affect and ego
depletion has generally not been found in past studies (Baumeister, Bratslavsky, Muraven &
Tice, 1998; Bruyneel, Dewitte, Franses, & Dekimpe, 2009), a few exceptions have been found
(Ciarocco, Sommer, & Baumeister, 2001). In their meta-analysis, Hagger, et al. (2010) found a
significant relationship between negative affect and depletion although the effect size was small.
10
However, mood was not predicted to play a significant role in task performance in the current
study, as the experimental tasks were not strongly aversive.
Recovery from SR Depletion
Baumeister, Bratslavsky, Muraven, and Tice (1998) explain that resources for selfcontrol must be commonly replenished although all of the factors involved in furthering or
delaying replenishment are not known. One factor, however, has been examined in the
replenishment or recovery of executive function: periods of rest have been studied as one means
for recovery of self-control resources. While few studies have reported the exact amount of time
between tasks of self-regulation completed within experiments, this rest time is another variable
that could affect depletion. Hagger et al. (2010) found that the type of task completed in the
interim period between experimental tasks had some effects on depletion effect sizes. The effect
size of depletion was not influenced when participants completed questionnaires, had a specified
break between tasks, or completed a filler task. However, studies in which no interim period was
provided had significantly smaller effect sizes of depletion (Hagger, et al., 2010). This finding at
first seems to suggest that less depletion results when participants are given no break from
executive function tasks. However, Hagger et al. (2010) explain that their coding for interim
tasks used in analysis did not take into account the large variation in the amount of time to
complete interim tasks such as filling out questionnaires, and studies reporting no interim task
(coded as having no interim task) may have had an interim period of unspecified length.
In contrast with this questionable finding of decreased depletion with no interim period,
some research has supported the idea that periods of rest allow for recovery of resources of selfregulation. For example, Tyler and Burns (2008) found that periods of rest between depleting
tasks did reduce the effects of depletion. Specifically, they found that a ten minute interval
11
between tasks requiring executive control could decrease depletion effects and that a 3-minute
interval between depleting tasks provided more replenishment of resources than a 1-minute
interval. Furthermore, they found that given a relaxation manipulation in which participants were
instructed to try to let the effects of the first task subside and listened to relaxing music, a 3minute period of this relaxation manipulation resulted in performance that equaled the control
group who did not complete a depleting self-regulation task at all. This could suggest that efforts
to relax and rest could result in decreased depletion effects. The current study did not specifically
control for interim time between the two SR tasks, but recovery times were minimized by
directing participants to begin the second task almost immediately after completing the first.
Only the SAM mood measure, which took less than one minute, was administered in between the
experimental tasks.
Speech Processing and Working Memory
Because the nature of speech is transient, complex speech processing when speech input
is difficult to process may invoke the use of working memory. A study by Lunner and
Sundewall-Thoren (2007) addressed some working memory aspects of complex speech
processing. Their study involving participants who were experienced hearing aid users found that
hearing threshold levels predicted speech perception in a fairly easy listening environment, but in
more difficult listening conditions, working memory was more predictive of speech perception.
Their findings suggest that in adverse listening conditions, processing of speech requires greater
demands of working memory than in easy listening conditions. Ronnberg et al. (2010) provided
the possible explanation that modulated noise maskers (including speech) may function as
speech maskers, invoking working memory. In other words, to process speech sounds when they
12
are covered up by other simultaneous speech, working memory would be needed to piece
together the speech sounds that were not covered up.
Working memory was relevant to the current study because in some circumstances the
use of working memory may require executive function that would lead to depletion. Tasks of
simple working memory recall such as forward digit span tasks are not sensitive to depletion
(Schmeichel, 2007). However, more complex working memory tasks such as repeating a digit
span backwards have been shown to be depleting (ibid.). Because of the suboptimal condition of
the speech processing task in the current study, participants are expected to use more complex
working memory resources to glean understanding of words by relating past knowledge of words
with incomplete new information (Ronnberg, Rudner, Lunner & Zekveld, 2010). That is,
listeners must take the incomplete, modulated sounds that they hear in the partly-masked speech
of the target speaker and use this information to determine the best semantic and phonological
representation of it. This manipulation of items in working memory may require explicit
processing or executive function. Therefore, in addition to the attention regulation factors
discussed above, the effects of adverse listening conditions on working memory in the current
study may further contribute to SR depletion effects.
Processing Speed
Because of the transient nature of auditory input through speech, changes in auditory
processing speed can affect the ability to encode speech, which is necessary in recall of auditory
input. In other words, a person needs to be able to keep up with the sentences they hear in order
to remember them and repeat them back. One aspect of the current analysis focuses on the time it
takes participants to make forced choice responses in recognizing which target sentences they
have repeated. This measure may not require that the participant fully process the entire stimulus
13
sentence, because one or two keywords may be sufficient for recognition. However, participants
who cannot keep up with the sentences while maintaining selective attention to the correct target
could take longer to make decisions on the forced choice questions if their processing speed is
reduced. Due to selective attention demands, it is possible that speed will be affected in the
selection of the answer choice.
Various populations are known to experience decreased processing speed compared to
typical adults. Tun, Wingfield, Stine, and Mecsas (1992) found that elderly participants in their
study experienced greater decrements in sentence recall with increasing speech rate when
compared with younger listeners. Moreover, the older participants’ response times for picture
recognition were slowed more in a dual-task condition when compared to the younger
participants. This age by task interaction supports the idea that response times may be
differentially slowed in more cognitively demanding tasks.
Evidence of depletion in speed measures for participants in the current study are of
interest because slowed processing speeds are common after TBI (Madigan, DeLuca, Diamond,
Tramontano, & Averill, 2000) and one goal for future research is to differentiate the nature of
self-regulatory depletion effects for adults with and without TBI. Studies of the TBI population
have also shown decreased processing speed in general in individuals with TBI, and
disproportionately slower auditory processing compared to visual processing in particular
(Madigan et al., 2000). If depletion effects do cause further decreased processing speed,
populations who already have impairments in processing speed could be particularly severely
affected when processing speech in adverse conditions. Because the current study was intended
to lay the groundwork for a comparison study with adults with TBI, it is important for the current
analysis to provide comparison processing speed data from healthy adult participants.
14
The current study examined how measures of forced choice responding and self-paced
advancement through the experiment were affected within a complex speech processing task.
This study aimed to explore whether FCR and/or SPA times would demonstrate effects of
depletion. The findings will provide some evidence regarding whether complex speech
processing is a task of self-regulation that is subject to depletion and, more specifically, whether
the current time measures used in the experiment are sensitive to depletion effects.
To examine depletion effects, the current experiment tested for group differences for both
measures of FCR and SPA time. Because the only difference between Group A and Group B is
the order of self-regulation tasks (speech processing task before versus after inhibitory writing
task), a difference between groups would provide evidence of depletion. Additionally, the
current experiment looked for patterns within participants’ FCR and SPA times to examine
possible depletion effects over the course of the speech processing task. Finally, due to the nature
of the random order of target speaker cues within the speech processing task, switch costs were
compared for trials which required switching to a different target from the previous trial versus
those which maintained the same target speaker. This was examined to determine whether
greater attention regulation was required for switch versus nonswitch trials, which could in turn
affect self-regulatory depletion.
Based on the SR depletion literature, the current study set out to test the following
hypotheses based on the prediction that Group B, which completed the speech-processing task
after the writing task, would experience self-regulatory depletion relative to Group A:
Group mean times:
1. The mean forced-choice response time for Group B will be longer than for Group A.
15
2. When compared to Group A, Group B will have a longer mean self-paced advancement
time between trials.
Within-participant times:
1a. Patterns of participants’ individual forced choice and self-paced advancement times
for Group B will show increasing time over the course of the task due to a depletion
effect on task performance efficiency, when compared to Group A.
1b. Alternatively, a decreasing time for Group B compared to Group A over the course of
the experiment may be observed if participant impulsivity increases over the course
of the speech processing task, which could result from depleted self-regulatory
resources.
2. Forced choice times and self-paced advancement times will be longer for trials that
require switching to a different speaker from the previous trial compared to those
items that maintain the same target as the previous trial. This would be due to a
requirement of greater attention regulation for switch trials versus nonswitch trials.
16
METHODOLOGY
The current analysis is one component of a larger experiment that includes accuracy
measures for the sentence repetition task, discussed here, as well as a writing inhibition task and
standardized testing. For the purposes of the current study, only forced choice response times and
self-paced advancement times within the sentence repetition task were analyzed, with one
analysis including a comparison with a standardized test of processing speed. Other components
of the experiment will be analyzed in future studies.
Participants
Participants were recruited via email and word of mouth. A posting in a campus-wide
email update announced the need for participants for the study. In-class recruitment was also
conducted with sign-up sheets to gather contact information for potential participants who
wanted more information on the study. Fifteen healthy participants, aged 18-48, completed the
experiment. All but one were students at Bowling Green State University (the one exception was
employed as a secretary), and one was excluded during data analysis as a statistical outlier (as
explained further below). Participants were compensated with two $10 gift cards for their time
and participation. Table 1 lists relevant participant characteristics for participants included in the
analysis. Participants were screened for hearing loss before completing the experiment, and all
passed. Exclusion criteria included history of brain injury or neurological disease, drug/alcohol
abuse, and more than four semesters of non-English language study (to control somewhat for the
effects of experience in the part of the experiment involving non-native-speaker sentence
repetition). To test for differences between groups on measures of age, verbal IQ, and education,
t-tests were conducted to compare groups for each of these measures. Groups did not
significantly differ in age, verbal IQ or years of education; however, Group B’s age (M = 27.86,
17
SD 12.71) reached close to significantly older than Group A’s (M = 19.71, SD 1.80); t(6) = -1.69,
p = 0.07.
Informed consent was obtained from all participants, and all experimental procedures
were approved by the university Human Subjects Review Board. Participants were informed that
they would be completing two separate tasks as a part of two different studies, a deception that
was explained in a debriefing at the end of the first session of the experiment. This deception
seemed to have minimal impact on participants, as many participants stated that they had
forgotten that there were supposedly two different studies. Furthermore, none had additional
follow-up questions about the deception when they were invited to ask questions about the study
following the debriefing. The reason for this deception was that some SR studies have suggested
that having two “separate” studies can enhance depletion effects. Although Hagger et al. (2010)
found that having two different researchers resulted in greater depletion, only one researcher was
available for the current experiment.
Table 1
Participant Characteristics
Group A
Participant
Sex Age
ID
A1
F
18
Group B
92
Edu.
(yrs)
12
Participant
ID
B1
VIQ
Sex
Age
VIQ
F
44
109
Edu.
(yrs)
16
A2
F
19
96
13
B2
F
20
107
14
A3
F
19
99
13
B3
F
18
96
12
A4
F
20
109
15
B4
F
20
96
14
A5
M
18
84
12
B5
F
26
102
15
A6
F
21
105
15
B6
F
19
112
12
A7
F
23
111
16
B7
F
48
118
18
19.71
1.80
99.43
9.68
13.71
1.60
Mean
SD
27.86
12.71
105.71
8.22
14.43
2.15
Mean
SD
Note. VIQ = estimated verbal IQ; Edu. = education
18
Structure of overall study
The current study used a dual task paradigm similar to those of other self-regulation
depletion studies, but alternated the order of the two tasks rather than using depleting and nondepleting versions of the first task. Participants in the current study completed a self-regulatory
writing task either before or after completing the complex speech-processing task. The writing
task has been used previously as a depleting activity in a study by Schmeichel (2007). The
speech-processing task was developed for the current project, and was predicted to be demanding
of self-regulatory resources because it requires control of cognitive processes such as selective
attention and updating working memory.
Half of the participants (Group A) completed the speech processing task first and then
completed the inhibitory writing task. The other half of the participants (Group B) completed the
writing task first, followed by the speech processing task. For both groups, standardized testing
was completed 2-14 days after the participants performed the experimental tasks. Because the
inhibitory writing task and speech processing task were completed on one day and all of the
standardized testing was conducted on a separate day, controlling for time between experimental
tasks and standardized testing was not considered necessary.
Speech processing task
The current study analyzed data from only the speech processing portion of the broader
experiment. The speech processing task was completed using a computer in a sound-treated
booth. Participants were given task instructions and stimuli via speakers and a computer screen.
The speech processing task was run using E-Prime 2.0 software (Psychology Software Tools,
Pittsburgh, PA), which collected all time measures throughout the speech processing task. The
task consisted of instruction, familiarization, training, and assessment phases first. The
19
experimenter was present in the booth for the duration of these portions. When these phases were
completed, the experimenter stepped out of the booth, and the experimental phase was completed
independently by the participants. Participants were able to control the rate at which the
familiarization, training, and experimental portions were completed by tapping the space bar to
continue to the next item.
Stimuli. Sentences were selected from the IEEE corpus (IEEE, 1969), which is
frequently used in speech processing research because the sentences are phonemically balanced
and grammatically correct but with low context, making key words hard to predict. Each
sentence included five key words used for scoring accuracy (which was not analyzed as part of
the current study). For example, in the sentence, “The birch canoe slid on the smooth planks,”
BIRCH, CANOE, SLID, SMOOTH, and PLANKS are the key words; accurate repetition of
other words in the sentence was not counted toward overall accuracy. Sentence pair stimuli were
developed for a previous experiment (Krause, 2011). All sentences began with the word ‘the’ so
that onsets were matched. Also, positions of keywords were matched so, for example, the
second, third, fifth, sixth and seventh word of each sentence in the pair would be keywords as
opposed to function words. This was intended to “line up” keywords to overlap, although this
was not directly manipulated. Sentences pairs were edited using Praat software (Boersma, 2001)
so that sentences in each pair were the same length and began simultaneously. To achieve this
matching, the length of the sentences in each pair was measured, and then each sentence was
lengthened or shortened to be the average length for the pair. Pilot testing established that this
manipulation did not reduce how natural the sentences sounded. Sentences were trimmed to
include a 150 ms silence at onset using Goldwave software (www.goldwave.com).
20
Instruction Phase. The procedure began with an instruction screen which presented
visual, written instructions to participants along with recorded, spoken instructions. This was
followed by an opportunity to adjust the loudness of the speaker signal. Participants heard, “Now
you will have a chance to adjust how loud the sentences will be. Press the space bar to hear a
sample of how loud the sentences will be, and tell the experimenter if you want the sound to be
louder or quieter or stay the same.” The loudness was set to start at approximately 70 dB (based
on initial measurements and visual adjustment of the volume knobs on the speakers), and was
adjusted to the preference of the participant. No participants requested the loudness to be
changed.
Familiarization Phase. The goal of the familiarization phase was to familiarize the
participants with the experimental task of listening to two speakers simultaneously and repeating
back only the target speaker. For this first portion of the study, participants listened to recordings
of 10 sentence pairs that were spoken by a different pair of speakers than those used during the
experimental portion. The target speaker was presented alone as a sample at the beginning of the
sequence, followed by the ten simultaneous sentence pairs. After each sentence pair, participants
attempted to repeat only the sentence spoken by the target speaker while ignoring the distracting
speaker. The experimenter provided encouraging but nonspecific feedback during this phase,
only confirming whether participants had repeated the correct speaker if they asked. After the
participants finished the familiarization phase, they were asked to rate the effort required for the
task and then proceeded to the training phase.
Training Phase. The training phase of the procedure used the same two target speakers
as the experiment itself. During the training phase, participants listened to five recorded
sentences by the native-accented-English speaker alone and then repeated (spoke) each sentence
21
immediately after it finished playing. Next the participants listened to five sentences produced by
the non-native-accented speaker alone and immediately repeated each sentence. Finally,
participants listened to a 10-sentence set of the two speakers alternating in a pseudo-random
sequence, followed by the participants repeating the sentences back when each was finished
playing. Each presentation of the sentences throughout the training phase was paired with its
respective visual cue (a green schematic face for the native-accented speaker and a purple face
for the non-native-accented speaker, illustrated below in Figures 1 and 2). Participants were
prompted to rate their effort for this phase once it was completed on a scale of 1 – 10 (effort
rating scale depicted below in figure 4).
Assessment Phase. This portion of the training was a quiz to assess if participants could
identify which speaker was producing the sentence. Ten (non-competing) sentences were played
in pseudo-random order, and participants selected whether the speaker was the native- or nonnative-accented speaker (illustrated below in Figure 3). All participants scored 10 out of 10 on
this quiz, demonstrating that they were able to learn the associations between each speaker and
the speaker’s visual cue.
22
Figure 3
Quiz Screen. This illustrates the screen that
was displayed to test if participants could
correctly identify whether the nativeaccented or non-native-accented speaker
had spoken.
Experimental Phase. After the instruction, familiarization, training and assessment
phases were complete, participants progressed to the experimental phase which involved
listening to recordings of the two speakers simultaneously, each producing a different sentence,
with the participants attempting to repeat back the sentence produced by only the target speaker.
Before each trial, the participants were visually cued to listen to either the native- or the nonnative-accented speaker with an image of either the green or purple face and the text, “Listen and
repeat.” A microphone recorded each sentence repetition attempt.
After a brief pause for the sentence repetition attempt, the computer displayed a forcedchoice question which provided both sentences spoken by the speakers. Participants were asked,
‘‘Which choice best matches the sentence you repeated?” The speaker that was presented as
choice (a) or (b) was randomized. After the participant chose (a) or (b) in response to the forcedchoice question, the prompt “press the space bar when you are ready to continue” appeared on
the screen. Each participant completed the same self-paced sequence of 60 sentence pairs, but the
visual cue (and therefore the target speaker) for each trial was randomized for each participant.
At the end of the 60 trials of the experiment, participants were prompted to rate their effort using
23
the same scale as for the pre-experimental phases. While participants’ effort ratings will not be
analyzed in the current study, their ratings could be related to their response speeds.
Figure 4. Effort Rating. This illustrates the screen that prompted participants to rate their effort
for phases during the speech processing task.
The measures used in the analysis for the current study are forced choice response (FCR)
time and self-paced advancement (SPA) time. The measure of forced choice time is the time
between the appearance of the forced-choice question on the screen and the participant’s
selection of an answer choice. The measure of self-paced advancement time for each trial is the
time between the selection of the forced-choice answer and the participant hitting the space bar
to continue on to the next experimental item.
Inhibitory Writing task
All participants completed an inhibitory writing task either before or after the speech
processing task, but data from this portion of the larger experiment will not be analyzed for the
current study. This task required participants to inhibit their automatic thoughts of what to write
when selecting the words they used to describe their trip.
24
Half of the participants completed the inhibitory writing task first and then completed the
single-talker interference speech processing task. The other half of the participants completed the
speech-processing task first. The stimulus used for the writing task was a written prompt: “Write
a story about a trip or vacation that you took sometime in the past without using the letters a or n.
Keep writing until you are told to stop.” Participants were also given verbal instructions for the
task. Participants were given six minutes to write before they were asked to stop.
Standardized Testing
The final part of the overall study was standardized testing. This portion is also part of
the broader experiment, but most of the results will not be given here. All participants were
tested to determine their current abilities relative to cognitive processes which were important to
the experimental tasks. The Wechsler Test of Adult Reading (WRAT, Pearson, 2001) was
administered to assess verbal intelligence. The Repeatable Battery for the Assessment of
Neuropsychological Status (RBANS, Randolph, 1998) was administered to measure immediate
and delayed memory, verbal skills, visuospatial skills, and attention. Daneman and Carpenter's
(1980) Listening Span task was administered as an additional measure of verbal working
memory. The Decision Speed subtest of the Woodcock-Johnson III Test of Cognitive Abilities
(WJ-III, Woodcock, McGrew & Mather, 2001) was administered as a measure of non-verbal
processing speed. The Ruff Figural Fluency Test (RFFT, Ruff, 1996) was given to test design
fluency, a non-verbal measure of executive function.
Data Analysis
Data for correct FCR times and SPA times of participants were analyzed. Using the data
from the E-Prime output, the FCR times and SPA times were consolidated onto an Excel
spreadsheet. The standard deviation of each participant’s mean time from the group’s mean was
25
calculated. This revealed that the mean FCR time of one participant (A8) was 3.45 standard
deviations away from the mean of all of other participants. For this reason, the data for A8 were
not used for any other analysis of the data. Additionally, within each participant’s FCR times and
SPA times, data points over 2.5 standard deviations from that participant’s mean were removed
to eliminate outlying times (for further detail regarding the process of eliminating outliers, see
Appendix C).
One way ANOVAs were conducted to assess group differences on the forced choice and
self-paced advancement measures for participants in Group A versus Group B. All times for
participants in Group A were compared to all times for participants in Group B.
Because the original analysis combined all data within each group and did not take into
account which data points were associated with which participant, additional analyses were
completed using two repeated measures ANOVAs: a two-way, trial by group analysis and a
three-way group by trial by speaker analysis. These tests were run in order to treat the times for
each participant as a group of data versus having each time for each participant treated as
separate, individual data. To perform the two-way ANOVA, only the FCR and SPA times for
trials in which participants repeated the correct (target) speaker were used in the analysis, with
outliers removed. Each participant’s times were then grouped into six partitions: the first set of
ten trials, second set of ten trials, etc. The average time for each partition was then entered into
IBM SPSS Statistics Version 20 (SPSS IBM, New York, U.S.A) to be analyzed. To perform the
three-way repeated measure ANOVA (group by trial by speaker), the times for each participant
were separated into trials with a native speaker target and those with a non-native speaker target.
Three, twenty-trial partitions were then created for each participant’s responses for each target.
Each participant’s average time for each partition of each target was then entered into SPSS.
26
To examine each individual participant’s patterns in performance across the course of
the experiment, regression analysis was also completed for trial number (1-60) versus FCR and
SPA time. These individual regressions were then qualitatively compared between Group A and
Group B to detect patterns.
Because the qualitative analysis revealed a pattern of decreased time as the experiment
progressed for SPA time for all participants, a repeated measures ANOVA was conducted to
compare the average time for the first ten trials to the average time for the last ten for each
participant. This analysis was conducted to determine any between-group effects (difference in
groups’ performance when comparing the first partition to the last partition) or withinparticipants effects (difference between trial means of the first and last partition across
participants).
Finally, due to research which demonstrates the presence of switch costs in tasks that
require alternating attention, FCR and SPA times for trials in which participants were required to
switch from the previous stimulus were compared to trials in which switching was not required.
Outliers 2.5 or more standard deviations away from the mean were again removed from the data.
T-tests were conducted to test for group differences for switch versus nonswitch trials for all
participants FCR and SPA time. Additionally, a t-test was performed to determine group
differences for switch trials only, and a t-test to determine group differences for nonswitch trials
only was also conducted. Final t-tests were conducted to compare group difference scores, the
measure of the difference between switch and nonswitch trials, for FCR and SPA times.
27
RESULTS
Forced Choice Response Time
Group hypothesis 1. The mean forced-choice response time for Group B will be
longer than for Group A.
Overall group effects. A simple one-way ANOVA was used as a preliminary test of the
difference between FCR times for Group A (undepleted) and Group B (depleted), 1 with each
time measure for every trial entered as an independent data point in the analysis. The ANOVA
revealed that the mean FCR time for Group A (M = 2983.67, SD = 1060.44) did not
significantly differ from the mean for Group B (M = 2982.47, SD = 1137.36), F(753, 1) = .000,
p = .99, η p2 = .000. Figure 5 illustrates the mean FCR times for each participant within each
group. Means and standard deviations for each participant are provided in Appendix A.
Time (ms)
FCR Means
5100
4600
4100
3600
3100
2600
2100
1600
0
1
2
Participants
Group A=1; Group B=2
Figure 5. FCR Times by Group. This figure illustrates the means and standard deviations for
participants by group.
The use of the term “depleted” here and throughout the remainder of this paper is used to clarify which group
would be depleted if the hypothesis of the study is correct; it is not meant to assume that Group B was depleted.
1
28
Group effects considering trial. The results of the trial by group repeated measures
ANOVA using 6 partitions for each participants’ times (grouping the first set of ten times into a
partition, second set of ten times into a partition, etc.) showed no significant difference between
groups for FCR time, F(1,12) = .022, p =.886, η p2 = .002.
Group effects considering trial and speaker. This analysis was completed using three
partitions for each participants’ times (grouping each set of twenty trials into one partition in
which native-accented trials were compared with non-native-accented trials). Because only the
native or non-native-accented speaker trials were used within each partition, these twenty-trial
partitions allowed for relatively similar amounts of time values within each partition. Results of
this analysis showed no overall group differences for FCR time; F(1,12) = .025, p = .88, η p2 =
.002 or group by speaker interactions; F(1,12) =.81, p = .39, η p2 = .06. However, visual
examination of the data suggests that the two groups may have shown different patterns of
performance for native versus non-native speaker targets during the first twenty trials of the
experiment (Figures 6 and 7).
29
FCR time for NS trials
Time (ms)
4500
4000
3500
Group A
3000
Group B
2500
2000
1 to 20
21 to 40
Trial
41 to 60
Figure 6. FCR Times for Native-accented Speaker Trials. This figure illustrates the means and
standard deviations for groups for Native-accented speaker trials
FCR time for NNS trials
Time (ms)
4000
3600
3200
Group A
2800
Group B
2400
2000
1 to 20
21 to 40
Trial
41 to 60
Figure 7. FCR Times for Non-native-accented speaker trials. This figure illustrates the means
and standard deviations for groups for non- native-accented speaker trials.
30
Within-participants hypothesis 1a. Patterns of participants’ individual forced choice
times for Group B will show increasing time over the course of the task due to a
depletion effect on task performance efficiency, when compared to Group A.
Within-participants hypothesis 1b. Alternatively, decreasing time for Group B
compared to Group A over the course of the experiment may be observed if
participant impulsivity increases over the course of the speech processing task,
which could result from depleted self-regulatory resources.
Within-participant trends. For this analysis, each participant’s FCR times were plotted
against trial number over the course of the experiment. Based on visual inspection, all
participants demonstrated a relatively flat pattern for time to answer FCR questions as the
experiment progressed. For FCR time, Group B did not demonstrate more of a slope in either
direction than Group A's participants. However, as indicated by the large standard deviation for
group B, the variability of Group B participants’ slopes was greater. The average slope for Group
A was -4.87 ms per trial (SD = 3.81), and the average slope for Group B was -4.09 ms per trial
(SD = 12.70), indicating that the average decrease in time over the course of the experiment for
Group A was 63.55 ms, and for Group B was 64.97 ms. See Figure 7 for a representative
example of the slope of participants’ average FCR time over the course of the experiment.
Graphs for each participant’s time over the course of the experiments are provided in Appendix
B. Table 2 provides the R2 regression values for each participant. R2 values indicated that the
amount of variance accounted for by the progression of the experiment (trial number) was small,
8.00E-06 to .10.
31
FCRT
Time (ms)
7000
y = -5.1702x + 3031.3
R² = 0.0043
6000
5000
4000
3000
2000
1000
0
0
10
20
30
Trial
40
50
60
Figure 8. Representative Slope. This graph of participant A4’s data illustrates the average slope
of all participants.
Table 2
FCR Regression Results
Slope
Intercept
Participant (ms/trial)
(ms)
A1
A2
A3
A4
A5
A6
A7
B1
B2
B3
B4
B5
B6
B7
-0.5785
-3.3728
-5.8528
-5.1702
-0.1901
-10.264
-8.659
-21.448
-1.7503
-14.819
5.4733
16.072
-1.6454
-10.506
2575.6
2648.3
2930.8
3031.3
3093.9
3794.3
3601.2
3859.5
3127.4
4069.0
3013.9
2521.9
2660.8
2538.6
R2
0.0002
0.006
0.0094
0.0043
8.00E-06
0.0179
0.0105
0.0491
0.0009
0.0188
0.0064
0.0849
0.0009
0.0964
32
Within-participants hypothesis 2. Forced choice times will be longer for trials that
require switching to a different speaker from the previous trial compared to those
items that maintain the same target as the previous trial.
Switch Costs. A t-test comparing mean FCR times for Group A switch trials (M =
2981.31, SD = 347.93) versus Group B switch trials (M = 3023.36, SD = 556.23) revealed no
significant difference between groups; t(10) =1.81, p = 0.43. Additionally, no significant
difference was found between Group A nonswitch trials (M = 2950.64, SD = 410.67) and Group
B nonswitch trials (M = 2968.13, SD = 426.03); t(12) = 1.78, p = 0.47. No significant difference
was found between means of all participants’ switch trials and nonswitch trials; t (26) = 1.71, p =
.27
To further analyze switch costs, the mean difference scores (the mean of participants’
switch trials minus the mean of participants’ nonswitch trials) for FCR times were tested for
significant difference between groups. A t-test comparing the difference score mean for Group A
(M = 30.67, SD = 259.95) to the mean difference score for Group B (M = 55.23, SD = 164.08)
revealed no significant difference; t(12) =1.81, p = .42. 2
Self-Paced Advancement Time
Group hypothesis 2. When compared to Group A, Group B will have a longer mean selfpaced advancement time between trials.
Overall group effects. A simple one-way ANOVA was used as a preliminary test of the
difference between SPA times for Group A (undepleted) and Group B (depleted), with each time
measure for every trial entered as an independent data point in the analysis. The ANOVA
revealed that the mean SPA time for Group A (M = 812.06, SD = 569.33) did not significantly
Analyses of switch costs were also conducted with incorrect answer times included. These analyses also resulted in
no significant differences between switch and nonswitch trials.
2
33
differ from the mean for Group B (M = 825.19, SD = 490.67), F(751, 1) = .12, p = .73, η p2 < .000.
Means and standard deviations for each participant are provided in Appendix A.
SPA Means
Time (ms)
2200
1800
1400
1000
600
200
0
1
2
Particpants
Group A =1; Group B = 2
Figure 9. SPA Times by Group. This figure illustrates the means and standard deviations for
participants by group
Group effects considering trial. The results of the trial by group ANOVA using 6
partitions for SPA time was also not significant, F(1, 12) =.01, p = .94, η p2 = .001. Visual
inspection of the graph does indicate a decrease in variability over the course of the experiment
for Group A compared to Group B, whereas Group B’s variability appears to remain relatively
large over the course of the experiment.
34
SPA
Time (ms)
2000
1500
1000
Group A
500
0
Group B
1
2
3
4
5
Trial Partition
6
Figure 10. SPA Time over Trial. This figure illustrates group means over the course of the
experiment.
Group effects considering trial and speaker. This analysis using three, twenty-trial
partitions for each speaker showed no overall group differences for SPA time; F(1, 12) = .021, p
= .888, η p2 = .002 or group by speaker interactions; F(1, 12) = 2.055, p = .177, η p2 = .146.
Within-participants hypothesis 1a. Patterns of participants’ individual self-paced
advancement times for Group B will show increasing time over the course of the
task due to a depletion effect on task performance efficiency, when compared to
Group A.
Within-participants hypothesis 1b. Alternatively, decreasing time for Group B
compared to Group A over the course of the experiment may be observed if
participant impulsivity increases over the course of the speech processing task,
which could result from depleted self-regulatory resources.
Within-participant trends. SPA time for most participants in both groups showed a
negative (downward) slope over the course of the experiment, indicating that they took less time
35
to move on to the next question as the experiment progressed. The mean slope for Group A was
-12.80 ms per trial (SD = 10.07), and the mean for Group B was -12.90 ms per trial (SD = 8.21),
indicating that the average decrease in speed over the course of the experiment for Group A was
- 612.71 ms, and for Group B was -729.38 ms. Eight participants’ graphs showed sharper,
negative slopes ranging from -10.65 to -26.91. The remaining six had slopes ranging from
slightly positive, 0.20, to less sharply negative, -8.98. Table 3 provides the R2 regression values
for each participant. R2 values indicated that the amount of variance accounted for by the
progression of the experiment (trial number) was small to moderate 0.0002 to 0.6506.
Figure 11 illustrates a regression pattern which is representative of the general pattern of
most participants. Appendix B provides regression graphs for all participants.
Time (ms)
SPA
4000
3500
3000
2500
2000
1500
1000
500
0
y = -15.661x + 1566.7
R² = 0.2584
0
20
Trial
40
60
Figure 11. Representative Slope. This graph of participant B4’s data illustrates the average slope
of all participants.
36
Table 3
SPA Regression Results
Slope
Intercept
Participant (ms/trial)
(ms)
A1
0.1954
587.42
A2
-11.035
884.14
A3
-4.5095
632.23
A4
-17.852
1427.1
A5
-24.194
1605.7
A6
-25.893
1890.6
A7
-6.3938
1057.3
B1
-2.7277
1279
B2
-26.907
1794.1
B3
-10.645
1067.1
B4
-15.661
1566.7
B5
-8.9802
751.71
B6
-18.863
1222.4
B7
-6.5258
727.49
R2
0.0002
0.179
0.1802
0.2842
0.3051
0.1656
0.0409
0.0071
0.401
0.1337
0.2584
0.2168
0.6506
0.2641
Significance of within-participant trends. Because of the decreasing trends observed in
the regression analysis described above, a repeated measures ANOVA was conducted to
compare average SPA times for only the first ten versus the last ten trials for each participant.
This analysis did not find a significant difference between groups; F(1,12) = .003, p = .960, η p2 =
.000. However, a significant difference for trial partition (first vs. last) was found; F(1, 12) =
31.03, p = < .001, η p2 = .721. The groups behaved similarly with participants in both groups
progressing more quickly to successive trials as the experiment progressed.
Within-participants hypothesis 2. Self-paced advancement times will be longer for
trials that require switching to a different speaker from the previous trial compared
to those items that maintain the same target as the previous trial.
Switch Costs. A t-test comparing mean SPA times for Group A switch trials (M = 799.77,
SD = 236.69) versus Group B switch trials (M = 803.04, SD = 262.05) revealed no significant
37
difference between groups; t(12) =1.78, p = .49. Additionally, no significant difference was
found between Group A nonswitch trials (M = 806.83, SD = 286.98) and Group B nonswitch
trials (M = 857.16, SD = 327.23); t(11) = 1.78, p = .38. No significant difference was found
between means of all participants’ switch trials (M = 801.40, SD = 239.91) and nonswitch trials
(M = 831.99, SD = 296.84); t(25) = 1.71, p = .38.
An analysis of the mean difference scores (mean of switch trials minus mean of
nonswitch trials) for SPA times between groups revealed no significant difference in mean
difference scores for Group A (M = -7.05, SD = 179.04) compared to Group B (M = -54.12, SD =
100.09) ; t(9) =1.83, p = .28. 3
Analyses of switch costs were also conducted with incorrect answer times included. These analyses also resulted in
no significant differences between switch and nonswitch trials.
3
38
DISCUSSION
Forced Choice Response Time
The purpose of the present study was to explore the sensitivity of measures of time in a
complex speech processing task to self-regulatory depletion effects. The results of the ANOVA
which compared all of Group A’s times to all of Group B’s times did not find significant
difference between groups on the measure of FCR time: the mean for Group A (M = 2983.67,
SD = 1060.44) did not significantly differ from the mean for Group B (M = 2982.47, SD =
1137.36), F(753, 1) = .000, p = .99, η p2 = .000. This finding does not support this study’s first
hypothesis for group times predicting a longer mean time for group B. While the groups did not
significantly differ in time to answer the forced choice questions (all participants averaged
between 2 and 4 seconds to answer FCR questions), the mean time to answer questions for both
groups was high compared to the mean amount of time the control group of healthy adults took
to answer questions in Madigan et al.’s (2000) study using an auditory threshold- serial addition
test (AT-SAT) to compare healthy adults and individuals with TBI. The mean response time for
healthy adults in the Madigan et al. (2000) study was 1662 ms and the mean of the TBI group
was 2094 ms. The greater time in the current study could be because, unlike the responses to the
AT-SAT, which required participants to add together two digits held in working memory, the
measure of FCR time in the current study included the amount of time participants took to read
the FCR question and answer choices in addition to the time to select a response to the questions.
While it was assumed that the complex speech processing task required the use of higher
levels of attention requiring the involvement of working memory, the results of the study could
indicate that the task did not require significant use of executive function. Baddeley (2012)
explained that the phonological loop component of working memory requires minimal attention.
39
While the experimental manipulation involved the inhibition of attention to one speaker, it is
possible that the task did not highly tax working memory to elicit depletion effects. However, the
use of selective attention has been used on past research of depletion with significant effect
(Schmeichel, 2007), when participants were asked to ignore words on a television screen,
requiring regulation of selective attention.
Another likely reason which could explain why FCR time would not be different between
groups could be related to the nature of the speed measure. Measures of performance accuracy,
such as number of words remembered in recall tasks (Schmeichel, 2007) as well as the number
of actions illustrating inhibition (i.e. reduction of facial expressions), or endurance measures of
inhibition or persistence (i.e. amount of time participants could keep their arms in ice water) are
typically used in the depletion literature (Schmeichel, 2007; Vohs et al., 2008). Measures similar
to the forced choice response time which reflect processing speed have not been used in past
depletion literature.
The number of foils for each question could also have accounted for a lack of depletion
effects on time measures. There were only two possible answers for each question. Vohs et al.,
(2008) found that the number of choices made by participants affected depletion. For instance, in
one study the experimental group which made gift registry choices for twelve minutes showed
increased passivity (evidence of increased depletion effects) on a subsequent task of executive
function compared with the group who made choices for only four minutes. Additionally, the
pleasantness of choices was only effective in improving performance when only a small number
of choices were made. The sheer number of choices affected participants’ performance. Because
the present experiment only used a two foil answer choice set over only 60 trials, it is possible
that deciding between only two choices did not elicit depletion effects. Moreover, it was also
40
observed that participants in the present experiment did not slow down as the experiment
progressed. This suggests that deciding between two choices did not show depletion effects on
time measures even when participants repeatedly had to decide between two choices.
Yet another factor that could explain the lack of significant group difference for FCR
times could be related to compounding factors of conservation and depletion of resources.
Because Group A was aware that a second experimental task would follow the first speech
processing task, it might be that participants’ speed slowed in an effort to conserve executive
control resources. This conservation of resources was found in the study by Muraven, Shmueli,
and Burkley (2006) when participants anticipated the need for resources of self-regulation on a
later task. If a conservation attempt occurred in the present experiment, Group A participants’
speed might more likely be closer to a depleted Group B participants’ speed, assuming depletion
did occur.
Because speed measures were used throughout the experiment, results of the Decision
Speed subtest of the Woodcock-Johnson III Test of Cognitive Abilities (WJ-III, Woodcock,
McGrew & Mather, 2001) were analyzed to determine any group differences in decision speed
time which could affect FCR or SPA time. While a t-test revealed a significant group difference
of decision speed time for this subtest; t(11)= 2.2, p = 0.03, such that Group B was quicker than
Group A, a significant relationship was not found between individual participants’ decision
speed times during the standardized test and their FCR times during the experiment, r = -0.32, n
=13, p = 0.29. There was also no significant relationship between decision speed during
standardized testing and SPA time, r = -0.01, n=13, p = 0.98. This indicates that while the
randomly assigned groups were unequal in the decision time measure during the standardized
41
assessment, there is no evidence that it directly affected how participants performed during the
experimental task.
Because effects of self-regulatory depletion on emotional control have been demonstrated
in past research (Schmeichel, 2007), in the current experiment, changes in mood were recorded
with the use of the 10-point, Self Assessment Manikin Scale. While the present experiment was
not expected to cause considerable change in participants’ emotional state, the mood measure,
pleasure, was analyzed to ensure no group differences in mood occurred which could influence
depletion effects. The SAM scale was administered at three different times over the course of the
experiment: before the first task, between the two tasks, and after the second task. One
participant from Group A was excluded from this analysis due to missing data. Although a slight
decrease in groups’ mean pleasure rating occurred from participants’ first pleasure rating before
the first experimental task (the mean rating for Group A was 7.50 and for Group B was 7.71) to
the mean rating after both the writing and speech tasks were completed (the mean rating for
Group A was 6.33 and for Group B was 6.71), results of a repeated measures ANOVA revealed
no significant difference between groups for change in pleasure; F(1, 11) =.42, p = .53, η p2 = .04.
Self-paced Advancement Time
Like FCR times, no significant differences were found between groups for SPA time.
This refutes the second hypothesis for group times proposed for this project. One possible
explanation could be the automatic nature of the task measured by SPA time. While FCR time is
a measure of a the time it took to make a deliberate decision by selecting an answer choice, SPA
time was a measure of a more automatic action, hitting the space bar to continue to the next trial
in the experiment. The trend lines for most participants’ SPA times showed a downward slope as
the experiment progressed through the 60 trials, showing decreased time to move on between
42
experimental items. This supports the idea of the automaticity of the task and could indicate that
as the participants continued to move on throughout the experiment the task became more
automatic. Furthermore, because SPA times for Group B were not significantly shorter than
those for group A, the alternative hypothesis proposed for this study of increased impulsivity for
Group B (as a result of depletion on Group B) is also not supported.
Another possible explanation for the lack of group difference in SPA times could be
related to motivation. The study by Boksem, Meijman, and Lorist (2006) found that adequate
motivation can overcome depletion effects. It is possible that both groups of participants were
very motivated to finish the experiment quickly, as there were 60 trials, and they could control
the pace of the experiment. A study by Hockey and Earle (2006) provides some support for this
explanation. These authors found that subjective fatigue was reduced in participants who were
given high control over their work schedule compared with participants who were given low
control over the schedule of their work tasks. Because participants in the current experiment had
the control to move on at their own pace, they may have experienced less fatigue and increased
motivation to continue to successive trials.
Finally, as with the measure of FCR time, it is possible that measures of speed to
complete actions are not sensitive to depletion. While time measures have been used in the past
to measure persistence (Vohs et al., 2008), the time measures used in the current experiment
were not measures of endurance. One measure of time used by Vohs et al. (2008) that was more
similar to the present experiment was the amount of time participants continued to watch a video
clip that they were to be questioned about later on when the video contained static and faint
images of people talking. While the researchers found that the depleted group waited
significantly longer to notify the experimenter of the problem with the video, this was a single
43
time measure, whereas the current experiment used repeated measures of time over the course of
the experiment, and participants had to move on to get to the next trial.
It is interesting to note that while past research has shown that short interim periods or
recovery periods decrease effects of depletion, none of the participants in the current study
apparently allowed themselves time to recover as the experiment progressed. No participants
slowed down or waited longer between trials as the experiment progressed. This could also be
due to a lack of use of executive control during the experiment during the speech processing
task. If the speech processing task did not require participants to utilize self control, participants
possibly did not feel the need to conserve or rest and recover self-regulatory resources.
Another observation regarding SPA time was its apparent bimodal distribution within
each group, with three faster participants having lower variability and four slower participants
having higher variability within both Group A and Group B (see figure 9). Further research could
examine a possible explanation for why certain participants progressed more quickly with less
variability and why some participants progressed more slowly with higher variability. In
addition, the apparent increase in variability of SPA time for Group B for both target speakers
over the course of the experiment (see figure 10) could suggest that participants’ ability to act
consistently or regulate their advancement throughout the experiment was affected by the use of
prior executive function on the writing task.
Target Speaker Effects
Target speaker analyses indicated that neither speaker produced significantly longer FCR
or SPA time measures than the other. This indicates that participants did not have a harder time
inhibiting attention to one speaker more than the other. Additionally, groups did not significantly
differ for FCR or SPA time means for the two speakers. Both groups generally responded
44
similarly to each speaker. However, in the first twenty trials, it was observed that Group A’s
mean FCR time increased from trial one to trial twenty for native speaker trials, whereas Group
B’s mean FCR time decreased for the native speaker from trial one to trial twenty, and vice versa
for the first twenty non-native speaker trials (see figures 6 and 7). This observation of the first
twenty trials was not present for SPA times, which possibly further speaks to the automaticity of
the task measured by SPA time. This apparent interaction between target speaker and group was
not statistically significant, F(1,12) =.81, p = .385, perhaps due to high variability among
participants. For example, standard deviations for Group A native-accented speaker trials ranged
from 118.96 to 708.01 ms and from 179.54 to 728.04 ms for Group B. This broad range of
variability suggests an avenue for future study.
Switch Costs
The lack of difference between switch and nonswitch trials between groups and within
participants for both FCR and SPA times could be explained by the frequency of switching
between stimuli over the experiment. Participants did not receive multiple, successive trials of
the same stimulus to allow them to habituate or automate to one stimulus or the other. The
presentation of stimuli was randomized, with most participants receiving no more than 3 to 4
successive trials of the same stimulus during the experiment and four participants (A5, A6, B3,
and B7) receiving no more than 5 or 6 successive nonswitch trials in one instance during the
experiment. When switch cost was illustrated by Gopher, Armony, and Greenshpan (2000), it
was demonstrated on tasks that required switching compared to blocked trials of the same task.
The current experiment did not use recurring, blocked trials of a single stimulus, nor did the
nature of the task change.
45
Limitations and Future Directions
Some limitations to the study relate to the degree of generalizability. The sample size was
small (n=14) and may not be representative of the target population of healthy adults. In the past,
experiments demonstrating the effects of depletion have used larger sample sizes ranging from
twenty-five to more than one hundred participants (Schmeichel, 2007; Tyler & Burns, 2008;
Vohs, et al., 2008). This limitation of having a small sample size was also exacerbated by large
variability within and among participants. In addition, the majority of participants were college
students. A study by Dahm et al. (2011) found that depletion effects were significantly reduced
in older adults (aged 40-65) compared to younger adults (aged 18-25). While the ages between
groups did not significantly differ in the current experiment (p = 0.07), if age reduces depletion
effects, this could be a factor in why group B did not demonstrate depletion, since both 40+ yearold participants were in group B (depleted group).
Another limitation of generalizability is related to gender. Because all but one participant
used in the analyses was female, the sample did not adequately represent the male population.
However, the mean FCR and SPA times (3088.24 ms and 632.98 ms respectively) for the one
male participant whose data were analyzed did lie relatively close to the mean group FCR and
SPA times (2983.67 ms and 812.06 ms respectively).
An important limitation of the current study’s procedures was the lack of instructions
provided to participants regarding how quickly to answer the questions and move on to the next
item. If participants had been given instructions to answer and move on to the next question as
quickly as possible, the FCR and SPA times might have been less variable and possibly reflect
any group differences in times more clearly. The time measures observed within the speech
processing task possibly contain a lot of experimental noise because of the self-paced nature of
46
the experiment. This participant control of the time throughout the experiment might have
obscured differences in group times, but this could mean that any effects found may be more
meaningful (such as decreasing time for SPA trials over the course of the experiment for nearly
all participants), as they would be the result of natural effects on the experimental tasks.
A further limitation of the current study is its relevance to functional, real-life tasks. In
everyday situations, people are motivated to listen carefully to conversational partners and other
mediums of speech input for various reasons. The current experiment utilized sentences which
although grammatically correct, had little meaningful value to participants. The inclusion of
environment noise and/or distractions during conversation should also be explored to determine
if they would relate to depletion effects and simulate real-life situations.
Due to these limitations, future research on depletion within a complex speech processing
task should be completed with more participants to determine if the current findings for time
measures are similar to the broader adult population. Another avenue for future research would
be to investigate variability in relation to depletion effects. Specifically, individual characteristics
of participants with high variability and faster responses could be explored in comparison to
individuals with slower, more variable responses.
A further investigation of age effects on depletion could also be explored using measures
of speed. If age affected the depletion measures in the current task, a study comparing
differences in age on time measures of depletion would add to the knowledge base of depletion.
This investigation would also be of interest due to research indicating the pre-frontal cortex
involved in self-regulation does not fully mature until age twenty-five (Dahm et al., 2011).
Because the results of the regression analysis of SPA times showed increasing speed as
the experiment progressed, possibly due to the automatic nature of the task, an interesting
47
question would be how populations with problems automating tasks might perform on this task.
In addition, other populations having impairments in attention, such as individuals with ADHD,
could potentially demonstrate decreased FCR or SPA times and could warrant examination using
the speech-processing task of the current study.
Future analyses are planned that will examine FCR time in participants with a history of
TBI, who typically have attention deficits. While healthy participants may not have slowed FCR
or SPA time, it could be that this population, along with other populations with disorders of
cognition, would be more negatively impacted by depletion. For clinicians, this information
would be useful in planning therapy activities, arranging the environment, and in determining the
order of therapy tasks.
48
CONCLUSIONS
The current experiment did not find significant group differences of time measures for
either forced choice response or self-paced advancement times. Additionally, whether the target
speaker had a native or non-native accent did not affect this outcome. Results of the switch cost
analysis did not find significant difference between trials that required switching or alternating
attention to a different stimulus than the previous trial. These findings may indicate that the time
measures were not sensitive to depletion effects, or that the experimental speech processing task
did not require working memory or attention regulation to become taxed enough in order to
induce self-regulatory depletion. Findings demonstrated that SPA time did significantly decrease
over the course of the experiment for all participants, possibly reflecting the automaticity of the
behavior that was measured. Additionally, it was observed that the two groups may have shown
different patterns of performance for native versus non-native speaker targets during the first
twenty trials of the experiment although variability within participants may have obscured this
interaction effect. This research offers some insight into the nature of complex speech processing
for healthy adults, and lays the groundwork for future studies to explore differences in complex
speech processing between healthy and impaired populations.
49
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54
APPENDIX A
Participant Means and Standard Deviations
Participant
Group A
Group B
1
2
3
4
5
6
7
1
2
3
4
5
6
7
FCR Time
Mean
2560.80
2560.59
2761.07
2907.23
3088.24
3562.98
3367.36
3312.62
2992.81
3747.91
3130.94
2952.14
2602.70
2228.66
Std. Deviation
644.77
648.45
1001.52
1081.63
981.03
1148.63
1307.26
1411.63
876.03
1538.72
978.85
883.67
824.80
571.42
SPA Time
Mean
592.40
599.00
491.46
1016.49
958.43
1157.07
884.64
1210.84
1017.67
760.60
1161.50
502.47
682.34
531.71
Std. Deviation
222.59
377.39
161.42
439.82
632.98
901.26
488.47
462.96
618.91
419.65
441.25
270.22
350.84
218.12
55
APPENDIX B
Regression Graphs
FCR Time over Trial
4000
2000
0
20
8000
4000
0
0
20
8000
Time (ms)
4000
Time (ms)
0
0
20
8000
Trial
40
60
y = -5.1702x + 3031.3
R² = 0.0043
6000
4000
2000
0
0
20
Trial
40
6000
4000
2000
0
60
0
20
8000
4000
2000
0
20
8000
4000
0
40
60
Trial
40
60
y = -8.659x + 3601.2
R² = 0.0105
6000
2000
Trial
y = -10.264x + 3794.3
R² = 0.0179
6000
0
60
y = -5.8528x + 2930.8
R² = 0.0094
6000
2000
Trial
40
y = -0.1901x + 3093.9
R² = 8E-06
8000
60
y = -3.3728x + 2648.3
R² = 0.006
6000
2000
Trial
40
Time (ms)
y = -0.5785x + 2575.6
R² = 0.0002
6000
Time (ms)
8000
0
Time (ms)
A5 – A7
Time (ms)
Time (ms)
A1 - A4
0
20
Trial
40
60
56
SPA Time over Trial
4000
3000
2000
1000
0
Time (ms)
y = 0.1954x + 587.42
R² = 0.0002
0
20
4000
2000
0
0
20
Trial
40
4000
2000
1000
0
20
4000
2000
1000
Trial
40
60
y = -25.893x + 1890.6
R² = 0.1656
3000
0
60
y = -24.194x + 1605.7
R² = 0.3051
3000
0
60
y = -11.035x + 884.14
R² = 0.179
3000
1000
Trial
40
Time (ms)
A5 – A7
Time (ms)
Time (ms)
A1- A4
0
20
Trial
40
60
4000
3000
2000
1000
0
Time (ms)
y = -4.5095x + 632.23
R² = 0.1802
0
20
4000
2000
0
60
y = -17.852x + 1427.1
R² = 0.2842
3000
1000
Trial
40
0
20
Trial
40
60
Time (ms)
Time (ms)
A6 *one data point (13,5772) beyond 4000
4000
y = -6.3938x + 1057.3
R² = 0.0409
3000
2000
1000
0
0
20
Trial
40
60
57
FCR Time over Trial
y = -21.448x + 3859.5
R² = 0.0491
6000
4000
2000
Time (ms)
0
0
8000
4000
2000
0
20
8000
4000
0
Trial
40
0
20
Trial
40
Time (ms)
* B3 one data point beyond 8,000 (9, 8411)
8000
y = 5.4733x + 3013.9
R² = 0.0064
6000
4000
2000
0
0
20
Trial
40
4000
2000
0
60
0
20
8000
4000
2000
0
20
8000
4000
0
60
Trial
40
60
y = -10.506x + 2538.6
R² = 0.0964
6000
2000
Trial
40
y = -1.6454x + 2660.8
R² = 0.0009
6000
0
60
60
y = 16.072x + 2521.9
R² = 0.0849
6000
60
y = -14.819x + 4069
R² = 0.0188
6000
2000
Trial
40
y = -1.7503x + 3127.4
R² = 0.0009
6000
0
Time (ms)
20
8000
Time (ms)
8000
Time (ms)
B5 – B7
Time (ms)
Time (ms)
B1 – B4
0
20
Trial
40
60
58
SPA Time over Trial
2000
1000
Time (ms)
0
20
4000
2000
0
20
4000
2000
0
0
20
4000
2000
0
Trial
40
0
20
Trial
40
4000
60
60
y = -8.9802x + 751.71
R² = 0.2168
3000
2000
1000
0
0
20
4000
2000
1000
0
0
20
4000
2000
0
60
Trial
40
60
y = -6.5258x + 727.49
R² = 0.2641
3000
1000
Trial
40
y = -18.863x + 1222.4
R² = 0.6506
3000
60
y = -15.661x + 1566.7
R² = 0.2584
3000
1000
Trial
40
y = -10.645x + 1067.1
R² = 0.1337
3000
1000
60
y = -26.907x + 1794.1
R² = 0.401
3000
1000
Trial
40
Time (ms)
3000
0
Time (ms)
y = -2.7277x + 1279
R² = 0.0071
Time (ms)
4000
0
Time (ms)
B5 - B7
Time (ms)
Time (ms)
B1 – B4
0
20
Trial
40
60
59
APPENDIX C
Explanation of Outliers
As described in the main text, outlying data points for individual participants were
removed, and one participant (A8) was entirely removed from data analysis due to the
extraordinary difference between this person’s FCR times and the remaining participants’ FCR
times (3.5 standard deviations from the mean of all other participants).
Within each participant’s data, times having z score values that were above 2.5 were
removed as outliers and not included in data analyses. Hair et al. (as cited in Meyers, Gamst, and
Guarino, 2006) recommend, as a general heuristic, to consider cases with z scores greater than ±
2.5 as outliers. Additionally, the majority of the values removed as outliers, using a z score of
greater than 2.5 as the cutoff criterion, were participants’ times for their initial trial (trial 1).
Furthermore, there were only a few values within each participants’ times that met the cutoff
criterion and were removed from analysis.
The purpose of this appendix is to provide participants’ data in more detail for inspection.
The following tables provide each participant’s times and standardized z-scores for each of those
times. Bolded values in the following tables show times and z-scores which were removed as
outliers. Blank cells in all tables indicate trials for which the FCR response was incorrect because
only correct trials were used to determine outliers and in the analyses.
60
APPENDIX C (continued)
Table 1
FCR times and standardized scores Trials 1-15.
Trial
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A1
1998
3036
2028
2364
3565
3023
4233
2856
2437
4256
2567
Z
-0.80
0.43
-0.76
-0.36
1.06
0.42
1.86
0.22
-0.28
1.88
-0.12
A2
3139
3240
2103
2589
2710
3712
2947
2851
2462
5779
Z
0.52
0.63
-0.65
-0.10
0.03
1.16
0.30
0.19
-0.25
3.50
A3
5499 49771
2970
1618
2633
1880
3529
2941
3490
3728
3037
3075
1940
Z
0.31
-0.10
-0.31
-0.15
-0.27
-0.01
-0.10
-0.01
0.03
-0.09
-0.08
-0.26
7.39
A4
4993
2570
3094
3417
2983
2809
2747
2439
1635
6882
Z
1.63
-0.34
0.08
0.35
-0.01
-0.15
-0.20
-0.45
-1.10
3.17
A5
2880
3615
4403
1743
1973
3293
2957
3517
3572
2341
4217
2238
3095
6381
Z
-0.28
0.36
1.06
-1.29
-1.08
0.08
-0.22
0.28
0.33
-0.76
0.90
-0.85
-0.09
2.81
A6
4859
2529
2821 13426
4502
4016
4753
5287
4776
3775
2590
2178
2471
3446
Z
0.65
-0.70
-0.53
0.45
0.16
0.59
0.90
0.60
0.02
-0.66
-0.90
-0.73
-0.17
5.62
A7
4843
4199
1987
2792
3612
5045
2725
1854
2996
1624
2327
8007
Z
0.96
0.52
-1.02
-0.46
0.11
1.10
-0.51
-1.11
-0.32
-1.27
-0.78
3.16
B1
5414
2337
3703
4924
3457
2394
4876
2269
2367
3039
2953
16932
Z
0.78
-0.53
0.05
0.57
-0.05
-0.50
0.55
-0.55
-0.51
-0.23
-0.27
5.65
B2
5406
2609
3782
2814
3001
3143
2017
2276
4504
3819
3617
2618
2754
Z
2.32
-0.48
0.69
-0.27
-0.09
0.06
-1.07
-0.81
1.42
0.73
0.53
-0.47
-0.33
B3
7860
2395
4351
1367
6407
3012
1973
2849
8411
2525
2101
4925 11091
Z
1.99
-0.81
0.19
-1.34
1.25
-0.50
-1.03
-0.58
2.28
-0.75
-0.96
0.49
3.65
B4
2648
2420
4146
3066
3815
3262
1693
2828
2173
3950
2461
2097
3165
7156
Z
-0.50
-0.71
0.84
-0.13
0.55
0.05
-1.36
-0.34
-0.93
0.67
-0.67
-1.00
-0.04
3.55
B5
3410
2332
2773
2166
2504
3006
1718
2940
4372
2034
2034
2317
2558
10469
Z
0.19
-0.58
-0.27
-0.70
-0.46
-0.10
-1.02
-0.15
0.87
-0.79
-0.79
-0.59
-0.42
5.23
B6
2045
3804
2849
1627
4166
1806
4757
2907
3459
1901
1555
1466
4858
Z
-0.69
1.34
0.24
-1.17
1.75
-0.96
2.43
0.31
0.94
-0.85
-1.25
-1.35
2.55
B7
3713
2662
3559
2159
3941
2242
2166
2498
2490
1841
2191
1673
1864
6085
Z
0.405
1.513
-0.22 1.984
-0.11
-0.21 0.203
0.193
-0.61
-0.18
-0.82
-0.58
4.63 1.703
Note. Z = standardized score; empty cells = times for incorrect answers, as these times were not used in data analysis; bolded numbers = outliers.
15
2324
-0.41
1856
-0.27
4033
0.73
3055
-0.39
4148
0.24
3357
0.27
4486
0.26
2996
-0.19
2332
-0.58
1878
-0.88
2169
-0.20
61
APPENDIX C (continued)
Table 1 (continued)
FCR times and standardized scores Trials 16-30
Trial
16
17
18
19
20
21
22
23
24
25
26
27
28
29
2744
2096
1632
1802
2775
2241
2132
3126
1452
2443
5588
A1
Z
0.09
-0.68
-1.23
-1.03
0.12
-0.51
-0.64
0.54
-1.45
-0.27
3.47
A2
2551
1982
1990
1906
2793
1607
3896
2602
1513
3425
3123
3220
2196
2511
Z
-0.15
-0.79
-0.78
-0.88
0.13
-1.21
1.37
-0.09
-1.32
0.84
0.50
0.61
-0.55
-0.19
A3
3742
2489
2748
2203
4056
2660
4289
2536
1950
2432
1968
3227
2387
1663
Z
0.03
-0.17
-0.13
-0.22
0.08
-0.15
0.11
-0.17
-0.26
-0.18
-0.26
-0.06
-0.19
-0.31
A4
2780
1930
2162
2512
2896
4322
2997
3330
2975
5999
2850
1984
3103
Z
-0.17
-0.86
-0.68
-0.39
-0.08
1.09
0.01
0.28
-0.01
2.45
-0.11
-0.82
0.09
A5
4097
2613
1918
2853
1878
3069
3055
5740
5060
2324
3229
3345
3323
Z
0.79
-0.52
-1.13
-0.31
-1.17
-0.12
-0.13
2.24
1.64
-0.77
0.02
0.13
0.11
A6
3768
2939
3570
4295
2615
4043
3984
4358
2488
3350
2850
4262
2489
3480
Z
0.02
-0.46
-0.09
0.33
-0.65
0.18
0.15
0.36
-0.72
-0.22
-0.51
0.31
-0.72
-0.15
A7
2497
5012
3355
6409
4257
3846
3411
2393
5632
3082
5200
2785
4468
Z
-0.66
1.08
-0.07
2.05
0.56
0.27
-0.03
-0.74
1.51
-0.26
1.21
-0.46
0.70
B1
3096
2589
7503
7386
2566
6920
1429
2332
1844
2593
Z
-0.20
-0.42
1.66
1.61
-0.43
1.41
-0.91
-0.53
-0.73
-0.42
B2
3359
3882
2832
4060
1963
2154
3694
2568
2157
3380
2598
2260
3208
2182
Z
0.27
0.79
-0.26
0.97
-1.12
-0.93
0.61
-0.52
-0.93
0.29
-0.49
-0.83
0.12
-0.90
B3
4267
2107
3321
5148
2259
2160
3363
3375
3215
2830
4065
7166
4264
9558
Z
0.15
-0.96
-0.34
0.60
-0.88
-0.93
-0.32
-0.31
-0.39
-0.59
0.04
1.64
0.15
2.86
B4
2990
2673
5184
2043
3348
2123
5505
2032
3657
2805
4602
4569
Z
-0.19
-0.48
1.78
-1.04
0.13
-0.97
2.06
-1.05
0.41
-0.36
1.25
1.22
B5
3490
2942
2601
2929
2087
2693
2584
2560
1987
3546
4392
3531
2798
6783
Z
0.24
-0.15
-0.39
-0.16
-0.76
-0.32
-0.40
-0.42
-0.83
0.28
0.89
0.27
-0.25
2.59
B6
2349
3268
2406
1779
2746
3470
3459
2871
2559
3758
3074
2728
3363
Z
-0.34
0.72
-0.27
-0.99
0.12
0.95
0.94
0.26
-0.09
1.28
0.50
0.10
0.83
B7
1340
2022
2039
2050
2432
1589
2676
2386
1973
2235
1611
3043
1953
2647
Z
-1.23
-0.38
-0.36
-0.35
0.122
-0.92
0.423
0.065
-0.44
-0.12
-0.89
0.876
-0.47
0.387
Note. Z = standardized score; empty cells = times for incorrect answers, as these times were not used in data analysis; bolded numbers = outliers.
30
2282
-0.46
2302
-0.43
2825
-0.12
2117
-0.71
2545
-0.58
2924
-0.37
2595
-0.42
2060
-1.03
3241
-0.38
2482
-0.65
3184
0.03
1611
-1.19
3200
1.069
62
APPENDIX C (continued)
Table 1 (continued)
FCR times and standardized scores Trials 31-45
Trial
31
32
33
34
35
36
37
38
39
40
41
42
43
44
A1
2423
2424
2230
2590
2442
1721
3192
3233
1843
2413
2341
1837
2367
5251
Z
-0.29
-0.29
-0.52
-0.10
-0.27
-1.13
0.62
0.67
-0.98
-0.31
-0.39
-0.99
-0.36
3.07
A2
2417
2144
2355
1840
3673
2521
2722
1682
1849
1492
2933
1952
2582
Z
-0.30
-0.61
-0.37
-0.95
1.12
-0.18
0.05
-1.13
-0.94
-1.34
0.28
-0.82
-0.11
A3
2790
1779
2988
3122
2964
2633
2218
1703
2426
1850
2883
1969
2878
Z
-0.13
-0.29
-0.09
-0.07
-0.10
-0.15
-0.22
-0.30
-0.18
-0.28
-0.11
-0.26
-0.11
A4
1830
1916
5982
1636
5303
3241
2138
1754
2221
1960
Z
-0.95
-0.88
2.44
-1.10
1.89
0.20
-0.69
-1.01
-0.63
-0.84
A5
2460
2920
2363
2095
3548
2346
2220
2644
2041
4125
6171
Z
-0.65
-0.25
-0.74
-0.98
0.31
-0.76
-0.87
-0.49
-1.02
0.81
2.62
A6
7280
4465
2400
2839
3257
5199
2977
2920
5705
1944
1857
2538
3297
2410
Z
2.06
0.42
-0.77
-0.52
-0.28
0.85
-0.44
-0.47
1.14
-1.04
-1.09
-0.69
-0.25
-0.77
A7
2512
2142
4356
2462
5870
1483
3875
1996
2809
2562
1917
3235
Z
-0.65
-0.91
0.63
-0.69
1.68
-1.37
0.29
-1.01
-0.45
-0.62
-1.07
-0.15
B1
3393
3709
3191
2890
2654
2447
2784
2166
1662
4222
5710
2146
Z
-0.08
0.05
-0.16
-0.29
-0.39
-0.48
-0.34
-0.60
-0.81
0.27
0.90
-0.61
B2
3380
1932
1699
2387
4043
4007
3755
4174
3249
2749
2968
2178
5900
5668
Z
0.29
-1.15
-1.39
-0.70
0.96
0.92
0.67
1.09
0.16
-0.34
-0.12
-0.91
2.81
2.58
B3
6732
2216
2985
2359
3538
2522
4821
6164
3361
2993
4638
3517
2549
Z
1.41
-0.90
-0.51
-0.83
-0.23
-0.75
0.43
1.12
-0.32
-0.51
0.34
-0.24
-0.73
B4
3413
2660
3277
1530
3435
5957
3163
2201
2305
3830
2497
3023
Z
0.19
-0.49
0.06
-1.50
0.21
2.47
-0.04
-0.90
-0.81
0.56
-0.64
-0.16
B5
2671
2122
3374
2795
3378
2636
2170
2108
2735
2857
3906
4504
3239
Z
-0.34
-0.73
0.16
-0.25
0.16
-0.37
-0.70
-0.74
-0.29
-0.21
0.54
0.97
0.07
B6
2130
2736
3289
2003
1830
1170
2773
1628
2103
1847
2445
2358
2885
1704
Z
-0.59
0.11
0.74
-0.73
-0.93
-1.69
0.15
-1.17
-0.62
-0.91
-0.23
-0.33
0.28
-1.08
B7
2532
1933
1565
1929
2177
2257
2563
3594
1601
1716
3169
2153
1863
4660
Z
0.245
-0.49
-0.95
-0.5
-0.19
-0.09
0.283 1.556
-0.9
-0.76
1.031
-0.22
-0.58
2.871
Note. Z = standardized score; empty cells = times for incorrect answers, as these times were not used in data analysis; bolded numbers = outliers.
45
1868
-0.95
3778
1.24
4505
0.15
3552
0.46
2366
-0.74
3645
-0.05
6287
1.97
4719
0.48
1795
-1.29
2588
-0.71
3169
-0.03
4515
0.98
2021
-0.71
2013
-0.4
63
APPENDIX C (continued)
Table 1 (continued)
FCR times and standardized scores Trials 46-60
Trial
46
47
48
49
50
51
52
53
54
55
56
57
58
59
A1
2770
1959
2697
3162
2615
3026
2197
2005
2337
2955
2187
4106
Z
0.12
-0.85
0.03
0.58
-0.07
0.42
-0.56
-0.79
-0.40
0.34
-0.57
1.70
A2
3184
2023
2781
2186
1932
1762
2087
3093
1907
4111
2720
2633
5748
Z
0.57
-0.74
0.11
-0.56
-0.85
-1.04
-0.67
0.46
-0.87
1.61
0.04
-0.05
3.46
A3
2163
2019
2229
3042
1714
1824
7201
3571
2731
2664
2573
3768
1500
2404
Z
-0.23
-0.25
-0.21
-0.08
-0.30
-0.28
0.58
0.00
-0.13
-0.15
-0.16
0.03
-0.33
-0.19
A4
2717
1937
1520
2297
2797
3085
4076
3892
2480
4413
1772
2796
Z
-0.22
-0.86
-1.20
-0.57
-0.16
0.08
0.89
0.74
-0.42
1.16
-0.99
-0.16
A5
2471
3782
5887
3528
1480
1997
4498
2497
3663
4493
2104
2711
3086
2519
Z
-0.65
0.51
2.37
0.29
-1.52
-1.06
1.14
-0.62
0.41
1.14
-0.97
-0.43
-0.10
-0.60
A6
4723
3030
2497
4030
2731
2238
5096
3003
4166
2001
4805
6300
3004
Z
0.57
-0.41
-0.72
0.17
-0.58
-0.87
0.79
-0.42
0.25
-1.00
0.62
1.49
-0.42
A7
4686
1269
2586
2691
4277
5704
4906
3570
3027
2098
2135
2595
2269
3006
Z
0.86
-1.52
-0.60
-0.53
0.57
1.56
1.01
0.08
-0.30
-0.94
-0.92
-0.60
-0.82
-0.31
B1
3150
2686
4523
3538
2471
3361
2167
3689
1719
3255
3773
3317
1780
Z
-0.18
-0.38
0.40
-0.02
-0.47
-0.09
-0.60
0.05
-0.79
-0.14
0.08
-0.11
-0.76
B2
3547
3794
3117
1800
3068
4701
4116
3603
1285
2089
2459
3900
2714
1823
Z
0.46
0.71
0.03
-1.29
-0.02
1.61
1.03
0.52
-1.80
-1.00
-0.63
0.81
-0.37
-1.26
B3
4314
2746
2312
4311
2178
4173
3889
3266
2940
4854
5742
3632
2990
Z
0.17
-0.63
-0.86
0.17
-0.92
0.10
-0.05
-0.37
-0.53
0.45
0.91
-0.18
-0.51
B4
5175
2986
3980
1457
2489
2784
3305
3270
3909
3126
3369
2004
Z
1.77
-0.20
0.70
-1.57
-0.64
-0.38
0.09
0.06
0.63
-0.07
0.15
-1.08
B5
5871
2315
3224
2750
2723
3673
2128
3071
2827
2122
6019
2025
3244
Z
1.94
-0.59
0.05
-0.28
-0.30
0.37
-0.73
-0.05
-0.23
-0.73
2.05
-0.80
0.07
B6
2227
1973
3546
2607
3686
3369
3272
3681
3434
2241
1352
4035
2773
1708
Z
-0.48
-0.77
1.04
-0.04
1.20
0.84
0.73
1.20
0.91
-0.46
-1.48
1.60
0.15
-1.07
B7
2319
1931
2095
1624
1747
1728
2528
2245
1412
1866
1808
2671
1954
1843
Z
-0.02
-0.5
-0.29
-0.88
-0.72
-0.75
0.24
-0.11
-1.14
-0.58
-0.65
0.417
-0.47
-0.61
Note. Z = standardized score; empty cells = times for incorrect answers, as these times were not used in data analysis; bolded numbers = outliers.
60
3688
1.21
2861
0.20
1899
-0.27
2681
-0.25
3995
0.70
3184
-0.32
2870
-0.40
1775
-0.76
2184
-0.90
4362
0.20
2893
-0.28
2498
-0.46
1867
-0.89
2062
-0.34
64
APPENDIX C (continued)
Table 2
SPA times and standardized scores Trials 1-15
Trial
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A1
686
589
542
839
672
983
548
295
545
1379
1435
Z
0.231
-0.13
-0.3 0.799
0.179
1.333
-0.28
-1.22
-0.29
2.802
3.01
A2
1223
1293
739
758
764
702
786
508
3415
6395
Z
0.484
0.558
-0.02
-0
0.003
-0.06
0.026
-0.27
2.784
5.91
A3
870
787
690
976
1036
508
681
630
507
469
409
359
1761
Z
1.544
1.184
0.765 2.002
2.262
-0.02 0.726
0.505
-0.03
-0.19
-0.45
-0.67
5.4
A4
1072
1195
1476
1339
1184
1273
989
1446
834
3009
Z
-0.11
0.08
0.511
0.301
0.063
0.2
-0.24
0.465
-0.47
2.86
A5
1597
1700
3785
1414
1306
1576
1217
2086
488
561
1429
1260
3919
4575
Z
0.517
2.498 0.245
0.142
0.399 0.057
0.884
-0.64
-0.57
0.259
0.098
2.626 0.419
3.249
A6
3337
1836
1525
2061
1763
1700
1653
1594
1977
1495
987
628
5772
4767
Z
1.683 0.438
0.18
0.624
0.377 2.869
0.325
0.286 0.237
0.555
0.155
-0.27
-0.56
3.702
A7
1481
2106
1312
1571
748
1484
777
931
604
1063
459
3097
Z
0.975 2.071
0.678
1.133
-0.31
0.98
-0.26
0.009
-0.56
0.241
-0.82
3.81
B1
1652
2191
1604
1748
792
1223
875
811
1042
1345
981
1044
Z
0.538
1.367
0.464 0.686
-0.79
-0.12
-0.66
-0.76
-0.4
0.066
-0.49
-0.4
B2
1578
1583
941
2625
1226
816
1321
1509
1460
1393
1474
2420
4999
Z
0.614
0.62
-0.18 1.917
0.175
-0.34 0.294
0.528
0.467
0.383
0.484
1.662
4.873
B3
972
1026
1488
1689
1164
1063
1040
2044
649
561
809
1163
3675
Z
0.168
0.249
0.941 1.242
0.456
0.304
0.27
1.774
-0.32
-0.45
-0.08
0.454
4.216
B4
1912
1486
1459
1245
2320
1999
2203
1225
2492
1062
1147
1053
1311
3089
Z
1.267 0.482
0.432
0.038
2.019 1.427
1.803
9E-04 2.336
-0.3
-0.14
-0.32
0.159
3.436
B5
1173
1259
877
775
1072
900
615
1058
567
950
528
529
753
504
Z
2.123 2.404
1.158
0.825
1.794 1.233
0.303
1.748 0.147
1.396
0.019
0.023
0.753
-0.06
B6
1401
1211
1173
1279
1162
1024
966
824
951
890
1185
933
847
Z
2.048 1.507
1.399
1.701
1.367
0.974
0.809 0.404
0.766
0.592
1.433
0.714
0.469
B7
1021
764
922
569
920
1081
799
623
631
360
440
630
301
1572
Z
0.844
1.465
0.078 1.457
2.09
0.982
0.29
0.322
-0.74
-0.43
0.318
-0.97
4.018 1.854
Note. Z = standardized score; empty cells = times for incorrect answers, as these times were not used in data analysis; bolded numbers = outliers.
15
279
-1.28
470
-0.19
2289
1.076
1029
-0.23
1407
0.161
2871
2.223
1268
0.611
2637
2.603
559
0.121
876
0.552
435
-0.45
65
APPENDIX C (continued)
Table 2 (continued)
SPA times and standardized scores Trials 16-30
Trial
16
17
18
19
20
21
22
23
24
25
26
27
28
29
A1
315
524
430
514
905
968
719
442
434
522
758
Z
-1.15
-0.37
-0.72
-0.41
1.044 1.277
0.353
-0.67
-0.7
-0.38
0.498
A2
945
815
1255
966
810
679
252
514
845
249
710
388
252
267
Z
0.193 0.056
0.518
0.215
0.051
-0.09
-0.53
-0.26 0.088
-0.54
-0.05
-0.39
-0.53
-0.52
A3
473
438
350
531
374
523
550
387
543
447
418
571
452
412
Z
-0.17
-0.33
-0.71
0.076
-0.6 0.042
0.159
-0.55 0.128
-0.29
-0.41
0.25
-0.27
-0.44
A4
957
1260
1404
2572
1789
743
638
1577
992
785
1523
2877
3217
Z
-0.28
0.18
0.4
2.19
0.99
-0.61
-0.77 0.666
-0.23
-0.55
0.583
2.657
3.178
A5
1085
1356
612
667
771
837
760
651
888
668
1180
887
5474
Z
-0.07
0.19
-0.52
-0.47
-0.37
-0.3
-0.38
-0.48
-0.26
-0.46
0.022
-0.26
4.104
A6
2242
694
1044
764
831
1370
881
665
533
833
1713
493
678
622
Z
0.775
-0.51
-0.22
-0.45
-0.4 0.051
-0.35
-0.53
-0.64
-0.39
0.336
-0.68
-0.52
-0.57
A7
1629
1148
534
587
729
828
1980
778
640
591
801
690
530
Z
1.234
0.39
-0.69
-0.59
-0.35
-0.17
1.85
-0.26
-0.5
-0.59
-0.22
-0.41
-0.69
B1
973
2630
1813
1029
799
661
588
735
1690
729
Z
-0.51
2.043
0.786
-0.42
-0.77
-0.99
-1.1
-0.87
0.596
-0.88
B2
1290
1376
815
1851
812
820
683
1201
1463
2301
910
841
1593
2432
Z
0.255 0.362
-0.34
0.954
-0.34
-0.33
-0.5
0.144
0.47
1.514
-0.22
-0.3
0.632
1.677
B3
625
919
549
510
553
442
573
489
623
1549
304
641
442
862
Z
-0.35 0.089
-0.47
-0.52
-0.46
-0.63
-0.43
-0.56
-0.35
1.032
-0.83
-0.33
-0.63
0.003
B4
1831
743
882
1018
766
727
854
687
952
933
883
1620
Z
1.118
-0.89
-0.63
-0.38
-0.84
-0.92
-0.68
-0.99
-0.5
-0.54
-0.63
0.729
B5
343
569
353
332
324
282
273
289
362
340
332
378
318
319
Z
-0.58 0.153
-0.55
-0.62
-0.65
-0.78
-0.81
-0.76
-0.52
-0.59
-0.62
-0.47
-0.67
-0.66
B6
880
1010
1143
780
1420
1012
730
757
761
425
392
955
1229
Z
0.563
0.934
1.313
0.278 2.103
0.94
0.136 0.213
0.224
-0.73
-0.83
0.777
1.558
B7
487
533
390
240
975
677
410
611
454
274
426
618
659
685
Z
-0.24
-0.06
-0.62
-1.21
1.673 0.503
-0.55
0.243
-0.37
-1.08
-0.48
0.271
0.432
0.534
Note. Z = standardized score; empty cells = times for incorrect answers, as these times were not used in data analyses; bolded numbers = outliers.
30
879
0.947
723
-0.04
361
-0.66
944
-0.3
683
-0.45
472
-0.8
1244
-0.09
1210
0.155
536
-0.49
1327
0.189
305
-0.71
875
0.549
592
0.169
66
Table 2 (continued)
APPENDIX C (continued)
SPA times and standardized scores Trials 31-45
Trial
31
32
33
34
35
36
37
38
39
40
41
42
43
44
A1
422
983
429
855
361
501
681
560
369
458
364
600
595
496
Z
-0.75 1.333
-0.72
0.858
-0.97
-0.46
0.212
-0.24
-0.95
-0.61
-0.96
-0.09
-0.11
-0.47
A2
2431
363
533
470
295
260
581
398
799
281
336
386
319
Z
1.752
-0.42
-0.24
-0.31
-0.49
-0.53
-0.19
-0.38
0.039
-0.5
-0.45
-0.39
-0.46
A3
535
555
485
566
478
336
338
756
537
496
320
499
444
Z
0.094
0.18
-0.12
0.228
-0.15
-0.77
-0.76
1.05
0.102
-0.08
-0.84
-0.06
-0.3
A4
1261
1440
688
1699
548
744
789
772
1428
634
Z
0.181 0.456
-0.7
0.852
-0.91
-0.61
-0.54
-0.57
0.437
-0.78
A5
1782
730
2116
829
571
542
556
563
395
375
681
Z
0.595
-0.41
0.912
-0.31
-0.56
-0.58
-0.57
-0.56
-0.72
-0.74
-0.45
A6
767
943
854
919
593
939
900
3206
795
503
821
1357
714
6303
Z
-0.45
-0.3
-0.38
-0.32
-0.59
-0.31
-0.34 1.574
-0.43
-0.67
-0.4
0.041
-0.49
4.143
A7
796
713
342
652
853
479
361
220
345
1501
417
851
Z
-0.23
-0.37
-1.02
-0.48
-0.13
-0.78
-0.99
-1.24
-1.02
1.01
-0.89
-0.13
B1
1274
1338
2088
1079
1444
957
1089
1009
524
935
1067
1132
Z
-0.04
0.055
1.209
-0.34
0.218
-0.53
-0.33
-0.45
-1.2
-0.57
-0.36
-0.26
B2
877
863
719
1156
795
904
658
821
1384
640
495
578
450
604
Z
-0.26
-0.28
-0.46
0.088
-0.36
-0.23
-0.53
-0.33 0.372
-0.55
-0.73
-0.63
-0.79
-0.6
B3
625
368
289
729
629
2230
597
366
412
922
518
785
879
Z
-0.35
-0.74
-0.85
-0.2
-0.35 2.052
-0.39
-0.74
-0.67
0.093
-0.51
-0.11
0.029
B4
1069
1674
859
972
914
1384
525
1361
933
1070
845
1319
Z
-0.29 0.828
-0.67
-0.47
-0.57
0.294
-1.29
0.252
-0.54
-0.28
-0.7
0.174
B5
341
341
376
396
364
387
275
376
354
328
278
437
454
Z
-0.59
-0.59
-0.48
-0.41
-0.52
-0.44
-0.81
-0.48
-0.55
-0.63
-0.8
-0.28
-0.22
B6
765
419
502
451
605
531
359
348
1107
509
332
392
370
323
Z
0.236
-0.75
-0.51
-0.66
-0.22
-0.43
-0.92
-0.95
1.21
-0.49
-1
-0.83
-0.89
-1.02
B7
895
240
542
428
554
647
683
1053
700
449
559
579
372
396
Z
1.359
-1.21
-0.03
-0.48
0.019 0.385
0.526
1.98 0.593
-0.39
0.039
0.118
-0.7
-0.6
Note. Z = standardized score; empty cells = times for incorrect answers, as these times were not used in data analyses; bolded numbers = outliers.
45
369
-0.95
300
-0.48
502
-0.05
899
-0.37
607
-0.52
652
-0.54
998
0.127
963
-0.52
444
-0.8
693
-0.25
1123
-0.19
416
-0.35
436
-0.7
316
-0.92
67
APPENDIX C (continued)
Table 2 (continued)
SPA times and standardized scores Trials 45-60
Trial
46
47
48
49
50
51
52
53
54
55
56
57
58
59
A1
501
809
414
492
735
506
317
325
867
934
644
1255
Z
-0.46 0.687
-0.78
-0.49
0.413
-0.44
-1.14
-1.11 0.903
1.151
0.075
2.342
A2
401
295
430
579
255
587
244
809
471
492
591
276
512
Z
-0.38
-0.49
-0.35
-0.19
-0.53
-0.18
-0.54
0.05
-0.3
-0.28
-0.18
-0.51
-0.26
A3
412
371
588
537
334
583
515
453
366
302
230
322
336
260
Z
-0.44
-0.62
0.323
0.102
-0.78 0.301
0.007
-0.26
-0.64
-0.91
-1.23
-0.83
-0.77
-1.1
A4
1233
452
659
413
941
370
810
473
701
605
645
972
Z
0.138
-1.06
-0.74
-1.12
-0.31
-1.18
-0.51
-1.03
-0.68
-0.82
-0.76
-0.26
A5
516
448
661
476
1212
701
1279
573
221
362
596
891
323
626
Z
-0.61
-0.67
-0.47
-0.65
0.053
-0.43
0.116
-0.55
-0.89
-0.76
-0.53
-0.25
-0.79
-0.5
A6
583
717
685
846
366
325
1933
1380
608
577
422
578
564
Z
-0.6
-0.49
-0.52
-0.38
-0.78
-0.82
0.518
0.06
-0.58
-0.61
-0.73
-0.61
-0.62
A7
515
610
2339
856
459
677
663
1028
907
2062
673
588
514
1303
Z
-0.72
-0.55
2.48
-0.12
-0.82
-0.44
-0.46
0.18
-0.03
1.994
-0.44
-0.59
-0.72
0.662
B1
673
547
903
741
1300
1835
1216
1047
1378
1685
1488
2013
3111
Z
-0.97
-1.16
-0.61
-0.86
-0
0.82
-0.13
-0.39
0.116
0.589
0.286
1.093
2.783
B2
445
362
593
432
546
354
464
580
450
534
601
369
333
406
Z
-0.8
-0.9
-0.61
-0.81
-0.67
-0.91
-0.77
-0.63
-0.79
-0.69
-0.6
-0.89
-0.94
-0.85
B3
525
476
620
1147
616
742
736
327
404
474
431
391
3503
Z
-0.5
-0.57
-0.36
0.43
-0.37
-0.18
-0.19
-0.8
-0.68
-0.58
-0.64
-0.7
3.959
B4
970
595
926
710
982
1553
965
1060
761
874
787
1044
Z
-0.47
-1.16
-0.55
-0.95
-0.45
0.605
-0.48
-0.3
-0.85
-0.65
-0.81
-0.33
B5
590
1240
320
375
311
939
484
315
309
484
328
331
1638
Z
2.342
-0.66
-0.48
-0.69
1.36
-0.12
-0.68
-0.7
-0.12
-0.63
-0.62
3.64 0.222
B6
298
326
301
391
275
291
646
302
258
216
258
514
311
360
Z
-1.1
-1.02
-1.09
-0.83
-1.16
-1.12
-0.1
-1.08
-1.21
-1.33
-1.21
-0.48
-1.06
-0.92
B7
355
398
428
487
333
267
300
316
300
288
504
260
421
362
Z
-0.76
-0.59
-0.48
-0.24
-0.85
-1.11
-0.98
-0.92
-0.98
-1.03
-0.18
-1.14
-0.5
-0.73
Note. Z = standardized score; empty cells = times for incorrect answers, as these times were not used in data analyses; bolded numbers = outliers.
60
390
-0.87
412
-0.37
335
-0.77
574
-0.87
412
-0.71
529
-0.65
691
-0.41
3977
4.115
353
-0.91
349
-0.77
986
-0.44
254
-0.87
289
-1.12
412
-0.54
68
APPENDIX C (continued)
Table 3
Participant A8 FCR times and standardized scores Trials 1-15
Trial
A8
Z
1
29755
3.453
2
10323
0.193
3
8629
-0.09
4
3421
-0.97
5
3252
-0.99
6
10260
0.182
7
9240
0.011
8
3524
-0.95
9
10001
0.139
10
11
8134
-0.17
12
24098
2.504
13
7171
-0.34
14
15796
1.111
15
4983
-0.7
23
11174
0.336
24
7816
-0.23
25
3490
-0.95
26
8843
-0.06
27
7005
-0.36
28
7598
-0.26
29
14007
0.811
30
2129
-1.18
38
39
12472
0.553
40
5679
-0.59
41
5841
-0.56
42
15306
1.029
43
6260
-0.49
44
3373
-0.97
45
2890
-1.05
Trial
46
47
48
49
50
51
52
53
54
55
56
57
58
59
A8
17633
7049 18978
7028
4317
2873
20432
5419 14302
8978
10175
6246 21852
6281
Z
1.419
-0.36
1.645
-0.36
-0.81
-1.06
1.889
-0.63
0.86
-0.03
0.168
-0.49
2.127
-0.49
Note. Z = standardized score; empty cells = times for incorrect answers, as these times were not used in data analyses; bolded numbers = outliers.
60
2528
-1.12
Table 3 (continued)
Participant A8 FCR times and standardized scores Trials 16-30
Trial
A8
Z
16
11490
0.389
17
18
7138
-0.34
19
8758
-0.07
20
2774
-1.07
21
5412
-0.63
22
5877
-0.55
Table 3 (continued)
Participant A8 FCR times and standardized scores Trials 31-45
Trial
A8
Z
31
20104
1.834
32
7330
-0.31
33
10267
0.183
34
4086
-0.85
35
36
7089
-0.35
37
6874
-0.39
Table 3 (continued)
Participant A8 FCR times and standardized scores Trials 46-60
69
APPENDIX C (continued)
Table 4
Participant A8 SPA times and standardized scores Trials 1-15
Trial
A8
Z
1
2590
1.444
2
1337
0.094
3
1086
-0.18
4
1573
0.348
5
1267
0.019
6
1259
0.01
7
1065
-0.2
8
1112
-0.15
9
979
-0.29
10
11
995
-0.27
12
1286
0.039
13
1510
0.281
14
2017
0.827
15
1024
-0.24
Table 4 (continued)
Participant A8 SPA times and standardized scores Trials 16-30
Trial
A8
Z
16
922
-0.35
17
18
726
-0.56
19
1547
0.32
20
824
-0.46
21
828
-0.45
22
2764
1.631
23
714
-0.58
24
1394
0.156
25
759
-0.53
26
3036
1.924
27
1031
-0.24
38
39
1113
-0.15
40
2013
0.822
41
937
-0.34
42
843
-0.44
28
1360
0.119
29
956
-0.32
30
781
-0.50
Table 4 (continued)
Participant A8 SPA times and standardized scores Trials 31-45
Trial
A8
Z
31
1003
-0.27
32
654
-0.64
33
6787
5.962
34
851
-0.43
35
36
903
-0.37
37
825
-0.46
43
859
-0.42
44
711
-0.58
45
919
-0.36
Trial
46
47
48
49
50
51
52
53
54
55
56
57
58
59
A8
838
801
640
1164
2210
982
725
756
710
1037
827
622
809
2063
Z
-0.44
-0.48
-0.66
-0.09
1.034
-0.29
-0.56
-0.53
-0.58
-0.23
-0.45
-0.68
-0.47
0.876
Note. Z = standardized score; empty cells = times for incorrect answers, as these times were not used in data analyses; bolded numbers = outliers.
60
619
-0.68
Table 4 (continued)
Participant A8 SPA times and standardized scores Trials 46-60
70
APPENDIX D
71