(Central) Auditory Processing Disorders Flashcards
Central Auditory
Nervous System (CANS
Overall pathway
Cochlear Nuclei through the Cortex
Brainstem – Integration of two signals
(binaural or dichotic processing) at level of
SOC
Corpus Collosum – Integrates auditory
information between 2 cerebral
hemispheres
Cortical level – Discrimination and
processing of phonetic and speech sounds
Development of Central Auditory Nervous
System (CANS)
Peripheral auditory system developed at birth
Central auditory system continues to develop through young
adulthood
Development proceeds from Brainstem to Cortex
Myelination occurs during maturation of the central auditory
system.
Corpus Callosum
Bundle of nerve fibers that connects the 2 cerebral
hemispheres that have complementary functions
Comprised mostly of myelin
The interhemispheric connections develop during the
first year of life but are not fully mature until early
adulthood (15-20 years of age)
Right and Left Hemispheres
Left Hemisphere
Dominant for comprehension
and production of language.
-Phonological analysis and
discrimination
-Sequencing auditory input
- Linguistic labeling
Right Hemisphere
Dominant for perception of
nonverbal sounds and musical and
prosodic stimuli
-Rhythm and stress
-Acoustic contour
-Auditory patterning and
temporal ordering
Handedness –
Right Handed - 96% are left brain dominant for language
Left handed – 70% are left brain dominant for language
15 % right brain dominant and 15% mixed brain dominant
Right Ear Advantage and CC
Language dominant hemisphere is usually the left
Both ears are ultimately connected to the left hemisphere, with input
from RE reaching left hemisphere slightly earlier than LE input
Information presented to the left ear must cross to the right hemisphere and
then across the CC to be perceived and labeled in the left hemisphere
Information presented to the right ear is directly transmitted to Left
hemisphere
Right ear advantage – More stimuli are successfully recalled from the
right ear than from the left.
REA decreases with age due to maturation of CC and pathways of
auditory nervous system
REA is observed in children until age 11
Redundancy
External Redundancy
Internal Redundancy
External Redundancy
Extrinsic - built into the
signal
Enhances
comprehension of signal
Syntax, morphology,
semantics
Internal Redundancy
Intrinsic - built into auditory
system
Multiple representations and
complex network
Cognitive capacity
What Is Auditory Processing?
Auditory = hearing
Processing = how the brain uses information
Katz: AP is not what we hear, but what we do with what we
hear
Musiek: AP is how well the ear talks to the brain and how well
the brain understands what the ear tells it
What Is Auditory Processing?
How different professionals see it
“The term “auditory processing” is used by speech language pathologists (SLPs),
psychologists and audiologist.
To a speech pathologist, the term is associated with linguistic processing.
To a psychologist, it refers to the auditory form of cognitive processing.
To an audiologist, it is deficit in the processing of auditory
input, specific to the auditory modality that occurs in the
auditory system prior to cognitive and linguistic operations.”
Auditory Processing Continuum
Different areas in the brain
Peripheral Auditory System – Perceive signal
CANS – Neurologic transmission of signal through brainstem to
upper cortex
Heschl’s Gyrus – Phonemic Processing to decode sounds and words
Temporal Lobe / Wernickes area - Language processing to decode
message. Attach meaning
Prefrontal/frontal lobe and motor strip – Executive function skills to
plan and execute a response
Auditory Processing Continuum
How SLPs and aud see the phonemic and language processing
Auditory Processing – Audiologist
Assesses audiological skill set associated with APD
Phonemic Processing – Audiologist and SLP
Audiologist focuses accurate reception of the phonemic signal (on non-
meaningful discrimination such as timing, patterns or competing signals
SLP focuses on accurate acquisition and discrimination of the phonetic code
to develop skills for reading, spelling and written language (phonemic
discrimination (b or p, rhyming)
Language Processing – SLP
Treats the functional impact of auditory processing disorders on language
and learning.
Auditory Processing
Disorder
Brain (not hearing) Disorder
Bellis: APD is when the brain can’t
hear
ASHA – (C)APD
Deficit in the processing of information that is specific to the
auditory modality
The deficit may be exacerbated in unfavorable acoustic
environments and that may be associated with difficulties in listening, speech understanding, language development, and learning
C)APD is a deficit in neural processing of auditory stimuli that
is NOT due to higher order language, cognitive, or related
factors.
Although (C)APD may co-exist with other disorders (e.g. ADHD,
LD, reading, language impairment, ASD), it is not the result of
these other disorders.
What is APD - ASHA
APD refers to difficulties in the processing of auditory information in the
central nervous system as demonstrated by poor performance in one or
more of the following skills:
Sound localization and lateralization
Sound discrimination
Temporal processing
- Auditory pattern recognition
- Temporal resolution
Auditory Performance Decrements with Competing Acoustic Signals and/or
with degraded acoustic signals
Characteristics of Children with APD
REPORTED DIFFICULTIES:
Following or understanding speech
In noisy situations
In poor acoustic situations
When the signal is fast or degraded
In the absence of multisensory supports
Localizing the source of a signal
Comprehending messages that rely on
tone of voice such as sarcasm or humor
Singing or appreciating music (e.g. nursery
rhymes)
Learning new or complex languages
RESULTING IN:
Delayed, inconsistent or inappropriate
responses in oral communication situations
Requests for repetitions (saying “huh” or “what”
often
Trouble following comiplex auditory directions
Inattention or distractibility in listening situations
Poor performance or auditory-dependent
multidisciplinary tests/subtests (e.g. receptive
language phonology)
Associated academic difficulties in reading,
spelling, and / or learning
Skills
Affected
Communication
May not speak clearly
May drop the ends of words
May not emphasize syllables
May confuse similar sounds (long after same-age peers)
Academic
May develop trouble reading, spelling, and/or writing
Phonetic awareness is difficult
Struggle with understanding instructions given verbally
May miss a great deal of information from class lectures
Easily distracted by background noises
Social Skills
May struggle telling stories and/or jokes
May have difficulty following conversations with peers
May take longer to respond to peer conversations
Risk Factors for (C)AP Deficits
Chronic Otitis Media
Genetics
Concussion / head injuries
Lyme disease
Lead poisoning
Neurological issues / seizures
Premature and / or traumatic birth history
SCREENING FOR
APD
Systematic observation of listening behavior and / or
performance of tests of auditory function to identify
those individuals who are at risk for APD
s This Child At Risk For APD?
8 y/o child on your caseload
demonstrates following
behaviors:
Difficulty following oral
directions
Difficulty hearing and
listening in BGN
Requires frequent repetition
of information
Does this child have:
Sensorineural HL?
Fluctuating conductive HL
related to OME?
Undiagnosed language
deficits?
Undiagnosed learning
disability?
Undiagnosed cognitive
deficits?
Disorder of attention?
Lack of motivation?
APD SLP Screening Protocols
- Questionnaires or checklists
-Children’s Auditory Processing Performance Scale (CHAPPS) by Smoski, 1998
-Screening Instrument for Targeting Educational Risk by Anderson 1989
(S.I.F.T.E.R)
-Fisher’s Auditory Problem Checklist (Fisher 1985) for Kdg to Grade 6 - Speech and Language Evaluation
- SCAN-3 for Children APD Screening Test
-Gap Detection
-Dichotic testing
- Auditory figure ground
- Screening Questionnaires
- Children’s Auditory Processing Performance Scale
(CHAPS) - Screening Instrument for Targeting Educational Risk
(S.I.F.T.E.R) - Fisher’s Auditory Problems Checklist
Children’s Auditory Processing Performance
Scale (CHAPS)
Assesses parent’s and/or a teacher’s judgment of a child’s
listening ability as compared to his or her peers.
Rated on a scale from -5 (cannot function at all) to a +1 (less
difficulty), the following listening conditions are assessed:
* Noise * Quiet * Ideal * Multiple Inputs
* Auditory Memory/ Sequencing * Auditory Attention Span
Screening Instrument for Targeting Educational Risk
(S.I.F.T.E.R
- The student’s classroom teacher completes the S.I.F.T.E.R, a rating scale
designed to “sift out” students who are educationally at risk, possibly as a
result of hearing or other auditory problems. - The S.I.F.T.E.R. compares the student to his or her classmates.
- Appropriate for Grades 1 -5
- Consists of 15 questions, 3 in each of 5 areas
Academics, Attention, Communication, Class participation, School Behavior
Fisher’s Auditory Problems Checklist
25 item checklist of auditory behaviors / characteristics associated with
13 categories of auditory processing skills
Can be completed by any referral source (parent, teacher, SLP)
Each item has value of 4%.
Observer places a checkmark next to each item that is consistent with
exhibited behavior of the child.
Items not selected are multiplied by 4 to determine total percentage.
Cut –off score of 72% to ID children at risk for (C)APD
- SLP Evaluation
Assessment of receptive and expressive language
o Comparing a student’s performance on tests that tap auditory perceptual
abilities and those that tap language abilities can assist in determining if a
referral for CAP testing is appropriate.
o Age-appropriate performance on speech and language tests and poor
performance on auditory perceptual tests suggests APD referral.
o Age-appropriate performance on auditory perceptual tasks and difficulty on
linguistic tasks may suggest need for comprehensive language assessment
LP EVALUATION
Celf – 4: Children with APD had the most difficulty with:
Following directions
Recalling sentences
Formulation of sentence
Forward number repetition (representing a memory task
- Screening Test for APD - SCAN 3: C/A
Ages and the type of testing
SCAN-3 for Children Ages 5-12
SCAN-3 for Adolescents & Adults Ages 13-50
Screens three Auditory Processing Skills:
1. Temporal Processing
2. Listening in Noise (Monaural Low Redundancy Test)
3. Dichotic Listening
