This document discusses disorders of the auditory nervous system, including acoustic neuromas and auditory neuropathy spectrum disorder. It begins by categorizing auditory nervous system disorders as affecting the auditory nerve, cochlear nuclei, or higher pathways. Acoustic neuromas are benign tumors of the auditory nerve that can cause hearing loss and tinnitus. Auditory neuropathy spectrum disorder involves abnormal nerve transmission from the cochlea to brainstem. The document also covers evaluation, diagnosis and management of these conditions.

1. Ozarks Technical Community College
HIS 120

2.  Can be broken up into three categories:
◦ Disorders of the auditory nerve
◦ Disorders of the cochlear nuclei
◦ Disorders of the higher auditory pathways
 Pathology of the auditory nervous system is
often referred to as a RETROCOCHLEAR
pathology, meaning a disorder occurring after
the cochlea

3.  Acoustic Neuroma
 Auditory Neuropathy Spectrum Disorder

4.  A benign (non-cancerous) tumor that grows on
the auditory nerve (CN VIII)
 Also referred to as an acoustic tumor or
vestibular schwannoma
◦ Occur at a rate of 1/100,000 every year
◦ In 95% of cases, tumors are unilateral (one ear only)
 Classic signs of acoustic neuroma
◦ Asymmetrical, sensorineural hearing loss in the high
frequencies
◦ Poorer word recognition score in affected ear
◦ Unilateral tinnitus
◦ May also be associated with dizziness
◦ If the tumor is big enough to press on the facial nerve
(CN VII), may report facial weakness/numbness

5. Image from: f1000prime.com
Right Left
WRS(%) 76 100

6.  It is important that you refer patients to an
ENT physician if they exhibit an asymmetrical
hearing loss and unilateral ear symptoms
 Auditory brainstem response (ABR) testing
may be performed by an audiologist
 Magnetic resonance imaging (MRI) of the
internal auditory canals is the gold standard
for diagnosis, as ABR testing may miss small
tumors

7.  Do nothing
◦ If the tumor is small enough, it will be monitored
for growth
 Surgical removal
◦ Usually results in total hearing loss in affected ear
 Narrow-beam radiation (Gamma Knife) to
stop tumor growth, which preserves hearing

8.  May wear a hearing aid in the affected ear,
but hearing should be tested regularly to
monitor for changes in hearing sensitivity and
speech understanding

9.  I will refer to ANSD as auditory neuropathy
 Auditory neuropathy refers to a condition in
which there is normal cochlear function, but
the transmission of electrical information
along the auditory nerve, from the cochlea to
the brainstem, is dys-synchronous (not
smooth).

10.  Varies from patient-to-patient, which is why
it is referred to as a spectrum disorder
 Will exhibit a range from normal hearing to
profound SNHL
◦ Most often will find a mild to moderate SNHL that is
progressive (getting worse)
 Great difficulty understanding speech,
especially in the presence of fairly good
hearing thresholds
 Diagnosed based on audiometric findings,
absence of an ABR response, normal MRI

11.  Hearing aids may help
 Often hearing aids are of very limited benefit,
and cochlear implants are recommended in
these situations

12.  Nearly impossible to diagnose with certainty,
but there may be abnormalities along the
auditory brainstem that results in
sensorineural hearing loss
 Usually due to disease, toxicity, irritation,
pressure, trauma
◦ Stroke, anoxia, syphilis, congenital malformation,
aging, multiple sclerosis

13.  Minimal Auditory Deficiency Syndrome
 Central Deafness
 Auditory Processing Disorder

14.  The presence of language and learning
disabilities due to auditory deprivation in
young children
 The auditory deprivation is often due to the
slight/mild conductive hearing losses that
accompany undiagnosed/untreated otitis
media

15.  Characterized by:
◦ No response to puretone testing on the audiogram
◦ These patient’s cannot “hear”, but they have normal
acoustic reflexes and ABRs
 Usually due to several compromise of both
brain hemispheres due to a vascular lesion
◦ Very rare

16.  A deficit in the neural processing of auditory
stimuli that is not due to higher order
language or cognitive factors
 Difficulty identifying and interpreting auditory
information in the absence of peripheral HL
◦ The ear and the brain do not coordinate well
◦ Auditory information breaks down somewhere
between the ear and the brain

17.  Delay in development
◦ Auditory deprivation secondary to otitis media,
much like MADS
 Disordered development of the auditory
nervous system
 Specific central lesion
 May be acquired in adults due to head injury,
stroke, brain tumor, or multiple sclerosis
◦ More prevalent in males

18.  Behaves like they have a hearing loss
◦ Says “huh” or “what” frequently
◦ Inconsistent response to auditory stimuli
◦ Often misunderstands what is said
◦ Constantly requests that information be repeated
 Poor listening skills
◦ Inattentive
◦ Easily distracted
◦ Restless
 Difficulty understanding speech in noise
 Poor academic performance

19.  Difficulty with phonics and auditory
discrimination
◦ confuses words that sound alike
◦ Has problems with reading, spelling, and vocabulary
 Poor auditory memory
◦ Difficulty following oral directions
◦ Learns poorly through auditory channel
 Poor receptive and expressive language
 Gives slow or delayed response to verbal stimuli
 Difficulty understanding rapid speech or
unfamiliar dialect
 Issues with gross and/or fine motor skills
 Poor musical abilities
◦ Does not recognize sound patterns or rhythm
◦ Poor vocal prosody

20.  The individual MUST have:
◦ Normal hearing
◦ Normal intelligence
 May co-exist with:
 AD/HD*
 Learning disabilities
 Speech/language delays
 Reading disorder
 Autism spectrum disorder

21.  Educational Assessment
◦ Psychological/IQ testing
◦ Speech/language assessment
 Audiology Assessment
◦ Puretone and speech testing
◦ Tympanometry and reflexes
◦ OAEs
◦ Electrophysiology
 APD Battery
◦ Monaural tasks in background noise
◦ Auditory pattern recognition
◦ Binaural separation and integration
 Dichotic vs. Diotic stimuli
 Includes verbal and non-verbal stimuli

22.  Based on the results of the APD evaluation
◦ Where is the weakness?
 Specific skill training
 Modify the listening environment
 Assistive Listening Devices
◦ increase the signal-to-noise ratio
 Speech-Language Therapy
 Environmental modifications to reduce noise
and reverberation

23.  Extended time on assignments
◦ Format adaptations on homework questions
 Classroom VISUALS
 Classroom accommodations
 Written notes/note buddy
 Study guide
 Set of texts at home/books on tape
 Test-taking adaptations
◦ Quiet area
◦ Modified format
◦ Extended time
◦ Segmented testing over multiple days

24. Feel free to stop reviewing the
powerpoint now 

25.  Dichotic Tests(Simultaneous & Different
Stimuli):
◦ Binaural Integration
 Dichotic Digits (DD)
 Dichotic Sentence Identification (DSI)
 Staggered Spondaic Word (SSW) Test
◦ Binaural Separation/Selective Auditory Attention
 Synthetic Sentence Identification (SSI-CCM)
 Competing Sentences Test (CST)

26. • Requires BINAURAL INTEGRATION
• “Tell me all four numbers”

28. Musiek, Weihing. Brain and Cognition 76
(2011)

29. CompetingSentencesTest
◦BINAURALSEPARATION
“Tellmethesentenceinyourleftear”

30.  Diotic (Simultaneous and Same Stimuli):
◦ Auditory Patterning/Temporal Ordering
 Pitch Pattern Sequence (PPS)
 High vs. low pitch
 Duration Patterns (DP)
 Long vs. short
 Gap Detection

32. *Greater than 20 msec is abnormal

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