2/17/2012
Auditory Processing Disorders
The Functional Significance of
Diagnostic Tests
Prudence Allen, Ph.D.
National Centre for Audiology
Western Ontario University
London, Ontario, Canada
[email protected]
Contributors
Students
•
•
•
•
Chris Allan, Ph.D.
Funding
• Networks of Centres of
Excellence
Udit Saxena
Alejandra Mendoza
Blake Butler
•
•
•
•
CIHR
NSERC
CFI
ORF-RE
Children, their families,
our clinical colleagues
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WHAT IS REQUIRED OF A
CHILD’S AUDITORY SYSTEM?
Real World Needs
• Recognize familiar sounds quickly
• Learn new sounds
• Tolerate noise and stimulus
degradation
• Form auditory objects and position
them in space
• Listen to one sound and ignore
another
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What is Required of the
Auditory System?
• Signals must be audible
• Basic acoustic processing (discrimination and
resolution) must be good: spectral and temporal
clarity
• Binaural hearing must be functioning
• Selective, sustained and focused attention must
be good
• Many signals must be well learned and
predictable
• Integrity of the auditory nervous system must be
intact
Perceptual Development
• Factors
• Quality of sensory encoding
• Ability to attend to and explore that
•
•
encoded information
Prior experience and knowledge
Environment
• Most easily recognized stimuli are
those that are familiar and well learned
– why?
Gibson, E.J. 2000
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Processes of Perceptual
Development
• Neural patterns are reinforced in response to
frequently occurring stimuli (imprinting)
• Allows for rapid perception even with
degradation
• Increased control over attention – selective and
sustained (attentional weighting)
• When coded with prior knowledge stimuli are
strengthened and thus can be degraded
(unitization)
• Over time a finer level of detail is perceived
(differentiation)
Goldstone, R., 1998
What do pediatric audiologists
have to help them?
CURRENT CLINICAL
ASSESSMENT BEYOND
AUDIBILITY
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Auditory Skills
• Sound localization and lateralization
• Auditory discrimination
• Auditory pattern recognition
• Temporal resolution, masking,
integration, and ordering
• Auditory performance decrements with
competing or degraded signals
• Memory and attention
Asha, 2005
Comprehensive Assessment
Recommendations
• Thorough case history
• Non-standardized but systematic observation of
auditory behavior (e.g. checklists)
• Behavioural evaluation of
• Temporal process (ordering, discrimination, resolution
and integration)
• Binaural processes (localization and lateralization)
• Perception of low redundancy (filtered, compressed,
degraded) and dichotic speech
• Electrophysiologic evaluation
• Speech-language assessment
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Clinical Practice,
Emanuel et al., 2011, AJA
Of the 195 respondents, # reporting use always or sometimes
Dichotic
• SSW - 144
• Digits – 115
• SCAN,CS – 100
• Competing Sentences – 91
Monaural low redundancy
• SCAN – AFG 101; FW 104
• Speech in Noise – 132
Temporal Processing
• Pitch Pattern – 138
• Random Gap – 68
• Duration Pattern - 55
Binaural Interaction
• Binaural Fusion – 38
• MLD – 29
Electrophysiology
• ABR – 23
• MLR, Corticals - 13
Our experiences with this battery…
COGNITION, BRAINSTEM
NEURAL INTEGRITY,
DISCRIMINATION SKILLS, ETC.
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63 Children Referred for APD
Evaluation
Behavioral
Objective
Staggered Spondaic Word Test
(SSW)
Click evoked ABR at slow and fast
rates
Auditory Fusion Test –
Revised, a test of gap
detection
Acoustic Reflex Thresholds, ipsi
and contra 500-2kHz
Filtered Words
Surveys
Pitch Pattern Sequence Test
Cognitive Evaluation (Intelligence,
academic achievement,
language, phonology, memory,
attention)
Competing Words (words in
noise)
Also
APD = 2 tests > 2 sd below
expectations
Basis Auditory Abilities
-10
40 children met APD criteria
23 did not
23 Children with no APD diagnosis
0
Quiet Word
Discrimination Score
10
100
20
95
-10
40 Children with APD diagnosis
Right Ear
Not APD
90
Left Ear
APD
0
85
10
80
Right
Left
20
250
500
1000 2000 4000 8000
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Threshold (ms)
APD Test Results
100
95
90
85
80
75
70
65
60
55
50
10
20
30
40
Other Central Auditory Tests
Not APD
APD
Percent Correct
Percent Correct
Staggered Spondaic
Word Test
Auditory Fusion Test - Revised
0
100
90
80
70
60
50
40
ppsr
ppsl
wicr
wicl
fsl
fsr
RELATION TO COGNITIVE
SKILLS
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Intelligence (WISC) &
Achievement (WRAT)
Standard Score
130
Not APD
APD
115
100
85
70
Language (OWLS) &
Phonology (CTOPP)
Standard Score
130
Not APD
APD
115
100
85
70
OWLS
CTOPP
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Language Diagnosis By
APD Diagnosis
Receptive and
Expressive
APD
Expressive
Not APD
Receptive
Typically developing
0
20
40
60
Percent occurrence
80
100
Attention (TEA-Ch) and
Memory (WRAML)
16
Standard Score
Standard Score
16
13
10
7
4
13
10
7
4
TEA-Ch Composite
Scores
WRAML
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RELATION TO OBJECTIVE
MEASURES – BRAINSTEM
NEURAL INTEGRITY
Click ABR Wave Latencies:
APD & Non-APD
Right ear
7.0
7.0
6.0
6.0
Latency (ms)
Latency (ms)
Left ear
5.0
4.0
3.0
5.0
4.0
3.0
2.0
2.0
1.0
1.0
5
10
15
20
Age (years)
25
5
10
15
20
25
Age (years)
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Wave I Latencies
APD & Non-APD
2.50
2.00
1.50
Adults
1.00
5
10
15
20
25
Wave V latencies
APD & Non-APD
6.40
6.20
6.00
5.80
5.60
5.40
Adults
5.20
5.00
5
10
15
20
25
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V/I Amplitude Ratio
APD & Non-APD
Wave V amplitude
1.50
1.00
0.50
0.00
0.00
0.50
1.00
Wave I amplitude
1.50
Acoustic Reflexes
APD & Non-APD
Reflex Threshold
110
105
100
95
90
85
80
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Ipsi-Contra
Threshold Differences
APD & Non-APD
Average contralateral
threshold
130
120
110
100
90
80
70
70
80
90 100 110 120 130
Average ipsilateral threshold
RELATION TO SUPRATHRESHOLD DISCRIMINATION
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Frequency & Level
Discrimination
APD & Non-APD
Frequency dL at 1 kHz (Hz)
1000
Jensen & Neff 1993
25
(Maxon & Hochberg, 1985
Maxon & Hochberg
(1982)
Jensen & Neff (1993)
Freyman & Nelson, 1991
20
Level dL (dB)
100
10
He, Dubno & Mills
(1998)
Berg & Boswell (2000)
15
10
5
1
0
10
20
Age (years)
30
5
10
15
Age (years)
20
Temporal Resolution
APD & Non-APD
Wightman, Allen, Dolan, Kistler, &
Jamieson (1998)
Irwin, Ball, Kay, Stillman, & Rosser (1985)
Fitzgibbons & Wightman (1982)
35
Gap threshold (ms)
0
30
25
20
15
10
5
0
0
10
20
Age (years)
30
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Spectral Resolution
APD & Non-APD
Threshold (dB SPL)
80
Notched
Flat
70
Allen, Wightman,
Kistler, & Dolan
(1989)
Veloso, Hall, & Grose
(1990)
Hall & Grose (1991)
60
50
40
0
10
20
Age (years)
30 0
10
20
Age (years)
30
Masking Level Difference
APD & Non-APD
MLD
Thresholds
55
20
18
16
14
12
10
8
6
4
2
0
S0N0 - SπN0 (dB)
50
SπN0
45
40
35
30
25
25
30
35
40 45
S0N0
50
55
6
11
16
Age (Years)
21
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Other projects using this diagnostic criterion
TYPICALLY DEVELOPING
CHILDREN AND THOSE WITH
APD
Speech Evoked ABR
/ya/ with Rising and Falling
Intonation
RISING
FALLING
0.9
0.9
Pitch Strength
Pitch Strength
0.8
0.7
0.6
0.5
0.4
0.8
0.7
0.6
0.5
0.4
0.3
0.3
7
10 13 16 19
Age (years)
7
10 13 16 19
Age (years)
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Follow Up: Acoustic
Reflexes Growth Functions
Factors causing
shallower ARGF
compliance
b. Retrocochlear,
brainstem
pathology
0.4 ml
0.6 ml
Acoustic reflex magnitude (in mmho)
a. Decreased static
0.3
0.25
y = 0.0136x + 0.038
1.6 ml
0.2
y = 0.0072x + 0.056
0.15
0.1
y = 0.0068x + 0.029
0.05
0
0
5
10
15
Stimulus intensity (in dB SL)
Shallower Growth in
Contralateral Reflexes for
Children with APD
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Inhibition of OAEs
Butler et al., IJA, 2011
Temporal Integration
at Threshold
45
40
35
30
25
20
15
10
5
0
Adults & Typically
developing children
Threshold (dB SPL)
Threshold (dB DPL)
Children with APD
1
10
100
1000
Signal duration (ms)
45
40
35
30
25
20
15
10
5
0
1
10
100
1000
Signal duration (ms)
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Summary and final comments
REFLECTIONS ON OUR
DIAGNOSTIC BATTERY
How Useful is a Diagnosis of
APD Made Based Upon This
Conventional Battery?
• Results only loosely related to the
skills/abilities important to perceptual
development.
• Co-morbidity with other disorders is going to
be high.
• Underlying auditory neural integrity is often
compromised, both with and without the
diagnosis.
• Basic encoding abilities and often reduced,
with and without the diagnosis.
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