M.Sc. Neuro-cognitive Psychology
Course C – 2011/12
Reaction time and psychophysical
methods
Introduction
Dr. Zhuanghua Shi
Dr. Dragan Rangelov
Introduction
} 
} 
} 
} 
2
Know each other
Why a course on classical methods?
Structure of the course
Organizational remarks
http://www.psy.lmu.de/exp/teaching/courses/
Why a course on classical reaction time
and psychophysical methods
3
http://www.psy.lmu.de/exp/people/ma/shi/
Why a course on classical reaction time
and psychophysical methods
Experience
•  introspection
Cognitive
architecture
•  RT/errors
•  Thresholds
•  …
4
Neural mechanisms
• 
• 
• 
• 
http://www.psy.lmu.de/exp/people/ma/shi/
fMRI
EEG
TMS
…
Why a course on classical reaction time
and psychophysical methods
Complexity of neuro-cognitive phenomena requires their
analysis on different levels
}  Levels are characterized by different methodological and
research approaches
}  Analysis of RT/errors and psychophysical measures allows
for a precise understanding of many neuro-cognitive
phenomena
}  Starting point of deeper analyses of the neural
mechanisms
} 
5
http://www.psy.lmu.de/exp/people/ma/shi/
Example: Luminance illusion
} 
6
Stimuli intensity & sensation
} 
Sensation (perception) is biased by surround context
} 
Another example: Tube illusion
Example: Luminance illusion
} 
relationship between external stimuli and internal
sensation
?
Stimuli
7
Sensation
Psychophysics and Neuroscience
Psychophysics (classical)
} 
} 
behavioral relationships
Macro
Psychophysics (modern)
} 
} 
Neural mechanisms
Micro
EEG, MEG, fMRI, PET …
?
S
8
R
S
R
Another Example
} 
Tilt illusion
□  Zollner illusion
Psychophysics: relationship between background context and
target percept
Neuroscience: Neural mechanisms underlying these illusions
9
} 
Psychophysics: Behavioral measure
10
Schwartz, et al., 2007, NRN
} 
Neural mechanism
} 
} 
Electrophysiological measure
responses of populations of neurons to local orientation
stimuli
Repulsive tuning shifts in
primary visual cortex neurons
for space and time, for context
target differences of 15°
11
Explanation
} 
12
Tuning shift on neuronal level (Fairhall, Lewen et al,
2001)
}  Tuning shift caused by contextual stimuli, but
decoding mechanisms are assumed to be
unaware of it.
}  The brain receives the changed input, but do not
‘know’ that changes have occurred due to the
context à illusion occurs
Aims of the course
} 
To provide an overview of “classical” reaction time (RT)
and psychophysical methods
} 
with reference to their applications in current neuro-cognitive
psychology research.
To demonstrate the power
of purely “psychological”
tools for investigating
internal (mental) states
and processes
}  To provide an hands-on
introduction to using RT
and psychophysical methods.
} 
13
http://www.psy.lmu.de/exp/people/ma/shi/
Structure of the course
} 
Lecturers
} 
} 
} 
Dr. Dragan Rangelov
Dr. Zhuanghua Shi
Tutors
} 
} 
} 
14
Martina Zellin / Markus Conci
Stephanie Ganzenmüller / Heng Zou
Michael Hegenloh
http://www.psy.lmu.de/exp/people/ma/shi/
Structure of the course
Application
(Research
projects)
Theories
(Lecture)
15
http://www.psy.lmu.de/exp/people/ma/shi/
Structure of the course
Date
Lectures and seminars
Room
24. 10
General introduction
2301
Shi
31. 11
Reaction times methods - I
2301
Rangelov
7. 11
Reaction times methods - II
2301
Rangelov
14. 11
Reaction times methods - III
2301
Rangelov
15. 11
Research projects assignment
2301
Tutors
21. 11
Reaction times methods - practical
PC Pool
Rangelov
28. 11
Adaptive methods
2301
Shi
5. 12
Signal detection theory
2301
Shi
12. 12
Psychophysical methods – practical
PC Pool
Shi
19.12
Exam (Multiple choice)
2301
Shi
2301
Shi/Rangelov
…
6. 02. 12
16
Students’ conference
Structure of the course
} 
Practical work
} 
Three groups
} 
} 
} 
} 
Assignment: 15th Nov.
} 
} 
17
Group 1: Room 2301, Tuesday, 2-4 pm.
Group 2: Room 1201, Tuesday, 2-4 pm.
Group 3: Room 1201, Wednesday 2-4 pm.
15th Nov. – 6th Feb.
Conference: 6th Feb.
http://www.psy.lmu.de/exp/people/ma/shi/
Practical work
} 
Project A: Sensation Seeking (SS) and attentional
processes
} 
} 
18
The project examine whether the expression of this
personality trait modulates visual search performance and
related attentional processes.
High and low sensation seekers (SSs) were expected to differ
with respect to their reaction time (RT)-accuracy ratio, slopes
and intercepts of the RT x set size functions, distractibility and
time course of performance...
http://www.psy.lmu.de/exp/people/ma/shi/
Practical work
} 
Project B: Can actions influence time perception?
} 
} 
} 
19
Timing is a critical and often unnoticed component of almost
all our behavior. Perceptual time can be distorted, such as wellknown stopped-clock illusion.
Whether this illusory extension of perceived duration is a
mechanism for maintaining perceptual stability across a
saccade, of if other types of voluntary movements than
saccades can trigger the illusion, is still discussed controversial.
This project will investigate whether we can observe any
illusory extension of duration if it is started by a button press
…
http://www.psy.lmu.de/exp/people/ma/shi/
Practical work
} 
Project C: Memory adaptation in contextual cueing
} 
} 
} 
20
Our visual world is fairly stable and facilitates visual search for
objects. For example, finding the toaster in a kitchen is
facilitated by its specific location in the surround of other
kitchen items.
That means, learning the spatial context of a target object can
lead to attentional guidance ('contextual cueing').
In this project, we are interested in the consequences for visual
search when the toaster is relocated within the kitchen. In
particular, we want to investigate whether context-based
learning can be adapted to changes in target location, and how
the adaptation process is modulated by attention.
http://www.psy.lmu.de/exp/people/ma/shi/
Practical work
} 
Details of practical work will be presented by tutors
} 
} 
21
15th Nov.
Questions regarding the research projects will be answered
then
http://www.psy.lmu.de/exp/people/ma/shi/
Structure of the course
} 
Requirements for course credit points (5 CP)
} 
} 
} 
} 
Active participation
Exam (19th Dec.)
Written report (Research project)
Participation in the students’ conference
} 
} 
Best presentation award
Grades
Exam
30%
Report
60%
Presentation
10%
22
http://www.psy.lmu.de/exp/people/ma/shi/
Criteria for the evaluation of the
students’ presentation
} 
1. Clarity (i.e. coherence):
} 
} 
a coherent talk, which allows easy understanding of the
research question, the main findings and main conclusions of
the conducted research
2. Argumentation:
} 
23
How convincing are the arguments put forward in order to
support your hypotheses, research question and conclusions.
http://www.psy.lmu.de/exp/people/ma/shi/
Criteria for the evaluation of the
students’ presentation
} 
3. Understanding of the research methods and data
analysis:
} 
} 
How well do you understand the limitations and the
capabilities of the specific research method applied in the
context of the present project?
4. Timing of the talk:
} 
} 
24
20 minutes
good allocation of time for different parts
http://www.psy.lmu.de/exp/people/ma/shi/
Criteria for written report
} 
Clarity and argumentation
} 
} 
} 
} 
Format
} 
} 
Introduction
Methods/Results
Discussion
APA (American Psychological Association) style
Written report will be graded by 3 reviewers
25
http://www.psy.lmu.de/exp/people/ma/shi/
Course materials
} 
Lecture slides
} 
} 
26
http://www.psy.lmu.de/exp/teaching/courses/
Research projects related materials provided by correspondent
tutors
http://www.psy.lmu.de/exp/people/ma/shi/
Any questions or comments?
Next week: RT methods by Dr. Rangelov
27
http://www.psy.lmu.de/exp/people/ma/shi/