Aud 272 Apd

Front 1

Why care about testing CAPD?

Back 1

Understanding of behavior, remove blame, develop remediation, educational placement, differential diagnosis, site of lesion testing.
Determining if the deficit is fixed or plastic: shat conditions improve performance and can that be maintained? If fixed, what skills/behaviors can be improved?

Front 2

"Language"

Back 2

Employs pitch, duration and rhythm: tonal and temporal characteristics to convey meaning.
Language performance depends on: verbal working memory, phonological awareness (perception). These skills can be taught leading to improved receptive and expressive language.

Front 3

Phonological Working Memory

Back 3

Ability to process and hold verbal information in immediate attention.

Front 4

Phonological Awareness

Back 4

Ability to reflect and manipulate sound components of language.

Front 5

What is auditory processing?
List auditory abilities that belong to AP

Back 5

?
Ability to attend, discriminate, recognize, remember and comprehend. Depends on accurate timing of neural events. Involves attention, language, motivation and decision processes. Listener actively controls processing and constructs message.

Front 6

ASHA definition of auditory processing

Back 6

The efficiency and effectiveness by which the CNS utilizes auditory info.
Perceptual processing of auditory info in the CNS & the neurobiologic activity that underlies that processing and gives rise to electrophysiologic auditory potentials.

Front 7

Bellis definition of auditory processing

Back 7

Extraction of information at different stages of processing.
Complex interactions between sensory and higher-level cognitive/linguistic operations occurring simultaneously (parallel) and sequentially (distributed) throughout the system.

Front 8

Behaviors of auditory processing: temporal aspects of hearing

Back 8

Resolution (important for e.g. voice onset time)
Integration
Ordering (sequencing) (melody perception)
-“Boots” vs. “boost”
ISI of only 2ms needed to perceive 2 signals, but 17 ms needed to perceive order of signals.

Front 9

Behaviors of auditory processing: performance with competing messages

Back 9

Binaural separation (attend to signal in one ear only)
Binaural integration (keep signals from each ear separate)

Front 10

Behaviors of auditory processing: binaural interaction

Back 10

Binaural interaction: how the ears work together. (brainstem very important)
–Localization (direction of source)
–Lateralization (place in head)
–Binaural release from masking (MLD test)
–Detection of signals in noise
–Binaural fusion

Front 11

Behaviors of auditory processing: pattern recognition

Back 11

“He saw the snow drift by the window.” vs. “He saw the snowdrift by the window.”
Project vs. Project

Front 12

Behaviors of auditory processing: auditory closure

Back 12

Ability to "fill in the gaps"

Front 13

Auditory coherence/streaming

Back 13

How sounds occurring simultaneously will be perceived as grouped together (one source) or separate (two sources).
Ability to stream depends on most basically: audibility, normal temporal resolution, normal frequency resolution.

Front 14

Bottom-up processing

Back 14

Sensory and data driven.
Encoding of auditory signals. Depends on good peripheral hearing function and good signal.
**Bottleneck and subtlety principles**

Front 15

Top-down processing

Back 15

Central resources and concept driven.
Higher order cognitive, linguistic and other influences on processing.

Front 16

Phase locking

Back 16

A nerve will only respond to a particular phase of a signal.

Front 17

Bottleneck principle

Back 17

All information must pass through the cochlea and 8th nerve. Problems will show up very clearly.

Front 18

Subtlety principle

Back 18

The redundancy of internal pathways makes finding problems more difficult because system can more easily compensate when the problem is more central.

Front 19

Intrinsic or internal redundancy

Back 19

Built into CNS…multiple representations. Impacted by disorder.

Front 20

Extrinsic or external redundancy

Back 20

Built into signal (syntax, morphology, semantics) which enhance comprehension of the signal.

Front 21

Information extraction

Back 21

VIIIN: signal analysis re: intensity, frequency and time.
CN: contrast enhancement of intensity. Convergence/divergence. Differential cell responses.
SOC: codes binaural cues via con/divergence from both sides.
ID: modulation enhancement, binaural cue enhancement. Divides pathway into primary and diffuse systems.
MGB: primary connection between BS and cortex. Codes slowly changing stim (vowel/syllable duration contrasts, binaural coding, feature extraction, complex signal processing, integration with other modalities.
Primary Auditory Cortex: coding of rapid acoustic events for fine discrim. e.g. consonants, auditory space developed for localization.
Auditory Association Cortex: recognition of linguistic stimuli, comprehension of spoken lang, lang formation.

Front 22

Corpus Callosum

Back 22

4 parts: rostrum, genu, body, splenium.
Anterior commissure a separate structure.
Complex rich network, connections to most areas of the cortex, allowing for multimodality integration.
Auditory segment mainly in the posterior segment.

Front 23

What is APD?

Back 23

A deficit in the perceptual processing of auditory stimuli and the neurobiological activity underlying that processing.
Abnormal or misrepresentation of sounds in the auditory system which leads to difficulty listening and comprehending (especially in background noise).

Front 24

Signs of APD

Back 24

Normal peripheral hearing common
Inconsistent auditory responses, often misunderstands
Poor localization, discrimination
Poor AFG skills: understanding speech in noise/reverb
Poor auditory memory
Poor listening skills, trouble paying attention, concentrating, easily distracted
Trouble following instructions
Difficulty with rapid speech, degraded speech
Frequently says “huh?” or “what?”, asking for repetition
Relies on visual cues
Hx chronic OM
Difficulty following instructions
Gives slow/delayed response to verbal stim
Poor reading/spelling and academic achievement
Has language deficits, deficient phonemic skills, memory deficits, auditory memory, phonologic awareness
Lower self esteem and behavior problems

Front 25

APD vs LD vs ADHA vs OM

Back 25

APD: difficulty with perception or deriving meaning from incoming sounds.
LD: disorder in using language (spoken/written) decreasing ability to listen, think, speak, read, write, spell, math.
ADHA: academic or emotional difficulties from inattention, impulsivity, and hyperactivity.
OM: persistency of fluid in ME.

Front 26

Why the controversy of APD, ADHA and LD?

Back 26

1. Highly complex parallel (simultaneous) and sequential (distributed) processing.
2. Involves at lease 4 cortical levels including 15 or more areas in the brain.
3. Interconnected with other sensory modalities.

Front 27

Gestational age

Back 27

Time between the first day of the last menstrual period and the date of birth.
2 weeks longer than conceptional age; they are not synonymous terms.

Front 28

Corrected age

Back 28

Subtracting the number of weeks born before 40 weeks of gestation from the chronological age
Important if born premature…can’t expect a premie to be as developed as the full term infant

Front 29

When do we first hear in the womb?

Back 29

6-7 months GA. All auditory mechanisms seem ready somewhere between 20-30 weeks (premies born at 25 weeks react to sound).

Front 30

What is the final event that allows us to hear?

Back 30

Simultaneous mechanical, chemical, neural events.

Front 31

Sensory cell development

Back 31

Inner hair cells: mature at 14 wks GA, base before apex, neural connections before OHC, afferent before efferent.
Outer hair cells: maturing into the 3rd trimester, >24 wks
Innervation: afferent mature by 24 wks, develops up & down, efferent present at 22 wks but not hooked up.

Front 32

Neuromaturation

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Neural development prior to adult like responses.
Structural vs. functional development.
IE structure by end of 5 mo GA (20 wks): 26 wk GA earliest response.
BS structure functional by 30 weeks GA: 30 wks earliest response

Front 33

What do we hear in the womb?

Back 33

Average 85 dB SPL, low pass filtered (20-200 Hz).
Nearby voices may reach fetus.
Mostly mothers vocalizations.

Front 34

Postnatal hearing

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Acoustic reflex fully developed at birth with adult like thresholds.
ABR: 17 dB higher thresholds than adults. (But, what does an ABR measure???????)
Behavioral: some behavioral response to high levels, subtle responses at moderate levels: 55-60 dB at 500 and 4000 Hz at 2-5 wk using OPP, 15 -20 dB SPL at 5mo+ using VRA.
Infant-adult gap varies in development by frequency up to 10 years.

Front 35

Recording ABR after birth

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PCA (post conceptional age) of 35 wks required for reliable ABR for wave V id. Bipolar clicks with threhsold detection around 40 dB nHL.
ABR can be recorded as early as 27-28 weeks CA (30 GA). Wave I more prominent and prolonged (by .3-1.0ms) latency decreases after birth. Later waves are also prolonged in neonates. Interwave I-V is easily 5.0 ms (4.0 ms in adults). Infants more sensitive to changes in click rate.
Middle latency response: more affected by sleep in infants
Late evoked potentials: age 17

Front 36

OAE possible for PCA (post-conceptional age) of ______

Back 36

28 weeks

Front 37

Neuroplasticity

Back 37

Reorganize, adapt in response to internal and external changes: throughout life
–Stroke
–Auditory deprivation studies

Front 38

Cochlear structure and size is mature by

Back 38

22-26 weeks GA

Front 39

Cochlear function is mature by

Back 39

Term birth. Subtle aspects of cochlear function or efferent function mature by 33 weeks.

Front 40

Auditory nerve maturation

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Myelination by 1 year. Synaptic transmission by one year or more.

Front 41

Central auditory system maturation

Back 41

ABR at 30 weeks GA (BS structurally complete). New and more efficient synaptic connections and myelination continues into adulthood. Arborization (branching of dendrites). Myelination caudal to rostral, cortex continues into early adulthood. CC myelination starts 5-6 mo of age and complete in mid 20s. Last to develop and first to degenerate.

Front 42

Waves I and V of the ABR are adult-like by

Back 42

????

Front 43

Goal for APD testing

Back 43

ID presents of APD or confirm site of lesion?
Goal dictates approach
Always include: objective/physiological tests, linguistically loaded tests (e.g. SSW, comp sent), less loaded tests (e.g. dichotic digits, pitch pattern), tests with known sensitivity and specificity.

Front 44

Dichotic

Back 44

Different signal to each ear at same time

Front 45

Diotic

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Identical signal to each ear

Front 46

Monotic

Back 46

One or more signals to one ear only

Front 47

Monaural

Back 47

Using or involving one ear

Front 48

Binaural

Back 48

Using or involving both ears

Front 49

Interaural

Back 49

Between the ears

Front 50

Drawbacks to APD test battery

Back 50

Time: client fatigue, attention problems, busy clinic.
Complexity: many tests to choose from, need to test across different tasks.

Front 51

Patient factors affecting APD testing

Back 51

Hearing loss, WRS in quiet, cognition, medications/drugs

Front 52

Possible causes of CAPD

Back 52

Neurodegeneration, hypoxemia, toxicity, maldevelopment, etc.

Front 53

Comprehensive test battery

Back 53

Functional tests, questionnaire, pure tone & speech audiometry, immittance measures, evoked potentials, OAEs. For CAPD you want a subset of this betters that is sensitive, specific and efficient.

Front 54

Aims of APD assessment

Back 54

?

Front 55

CAPD subtypes

Back 55

Decoding, integration, prosodic, output-organization, associative

Front 56

CAPD management

Back 56

Top down: compensatory strategies
Bottom up: environmental changes, therapies

Front 57

Therapies for adults

Back 57

Formal auditory training (e.g. LACE)
Playing a musical instrument
Note taking
Audiobooks

Front 58

APD assessment can have 4 basic goals. What are they?

Back 58

1) Judge site of lesion
2) Screening prior to medical referral
3) Identifying communication disorders
4) Monitor disease progression