Chapter 11 Clinical Application

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Chapter 11
Clinical Application
Perry C. Hanavan, Au.D.
Outer Ear Resonance
• Influence of pinna
(p)
• Influence of ear
canal (c)
• Combine influence
(t)
• At 3000 Hz, the final
amplification (t) is
20 dB
Transformer/Amplifier
• Area ratio
– Thumbtack
• Lever
– crowbar
Middle Ear Muscles
• Tensor tympani
– Attached to malleus
– Innervated by V, trigeminal nerve
• Stapedius
– Attached to stapes
– Innervated by VII, facial nerve
• Middle Ear Muscle Function:
– Protect inner ear from excessive
sound levels
• When ear exposed to sound levels
above 70 dB, the muscles contract,
decreasing amount of energy
transferred to inner ear
Hearing Loss
• Audibility
• Identification
• Signal to
noise ratio
(SNR loss)
Audibility
Hair Cells
• Outer Hair
Cells
• Inner Hair
Cells
• OHC
movie
Hair Cells
• Outer Hair
Cells
• Inner Hair
Cells
• OHC
movie
Generate distortions
Traveling Waves
•
•
•
•
Traveling wave
Basilar membrane
Traveling Wave info
Cochlear Traveling
Wave
Central Auditory Path
Identification/Recognition
• Hearing loss affects the ability to correctly
identify or label sound(s)
– Vowels relatively easy
– Consonants more difficulty to identify
• Place of production errors common
• High frequency consonants (sibilants) extremely
difficult to identify
QuickSin/BKBSIN SNR Loss
UWO Plurals Test
• Test designed to test high frequency
consonant detection, and assist with
determining audibility.
Phoneme Perception Test
CI
• CI offers one treatment option
• Phonak remote Dynamic FM best for
classroom noise conditions
• Currently, addition of classroom
amplification with CI with FM shows no
benefit
Siemens Hearing Test (Free)
iOS: iTalkAtMoog
Ling 6 (iOS)($1.99)
Cochlear HOPE Words Lite and
HD
Cochlear HOPE App (Apple)
• Cochlear HOPE program
• Adopted from Speech Sounds and Speech
Sounds Vowels
• Listen to a word and matching their speech
production to what they heard.
• Vocabulary development also facilitated
• Each letter of alphabet has twenty different
flashcards
• In some instances, letter may have two different
speech sounds (for example, “A” as in “way” or “A”
as in “cat”)
Baldi (iOS App $4.99)
Auditory Verbal iPad ($3.99)
Hearing Aids
• Hearing aids
• FM remote microphones
• Phonak Dynamic FM best for background
noise conditions
• Extended high frequency bandpass
hearing aids (250-10,000 Hz)
• Non-linear frequency compression hearing
aids
Phonak Dynamic FM Recievers
Non-linear Freq Compresion
Classroom Amplification
• Phonak Dynamic FM
• Phonak Dynamic FM in Classroom
Otitis Media
Prevalent among children birth to 6. At-risk children for OM:
• Down Syndrome
• Cleft Palate (cranial facial)
• Treacher-Collins (cranial facial)
• 2nd-hand smoke
• Day-care
• Low income (Inner city, Native Americans, etc.)
• Bottle fed rather than breast fed
• Allergies
• Other infections (upper respiratory)
• Immune suppression (HIV, AIDS, etc.)
• Pacifier
• Family history
OME Tendencies
•
•
•
Language impairments
Poor phonetic processing
At-risk for developmental delays in perceptual
and phonemic awareness, thus leading to
difficulties with higher level language
functioning and reading
Specific Language Impairment
•
•
Characterized by difficulty with language that is not
caused by:
•
•
•
•
known neurological,
sensory,
intellectual, or
emotional deficit.
Can affect the development of:
•
•
•
•
vocabulary,
grammar, and
discourse skills,
with evidence that certain morphemes may be especially
difficult to acquire (including past tense, copula be, third person
singular).
SLI (cont.)
•
•
•
•
•
Children with SLI may be intelligent and healthy in all
regards except in the difficulty they have with language.
They may in fact be extraordinarily bright and have high
nonverbal IQs.
Children with SLI usually learn to talk late
child 3 or 4 years of age with limited vocabulary and
short utterances.
Likely to be the kinds of kids who are told by parents
and teachers they are smart but unmotivated and they
just need to try harder.
SLI (cont.)
•
•
•
•
Difficulty processing rapid acoustic speech cues
(temporal processing problem)
Difficulty identifying formant transitions, thus
difficulty identifying phonemes
Children of the Code
Paula Tallal (Temporal spectral deficits)
Dyslexia
•
•
•
•
•
•
Categorical perception difficulty
Reading ability is significantly lower
Difficulty perceiving consonant contrasts
Confuse sounds phonetically similar
May have deficits in processing the temporal order of
acoustic information (difficulty identifying phonemes and
judging the order in which the phonemes are heard)
Difficulty segmenting, discriminating and identifying
speech sounds
Types of Dyslexia
• Developmental phonological dyslexia difficulty with nonword reading.
– Changing the initial and middle letters of a word.
– Examples are mana (mama) and aufo (auto).
• Developmental surface dyslexia - difficulty in
reading irregular words.
– 25% English words are irregular, which means that
they violate English spelling-to-sound word rule.
– Examples: pretty, bowl, and sew.
Etiology of Dyslexia
• Heredity:
– Family gene carries the disorder
– Studies have shown that males are four times
more likely to have a reading disorder than a
female;
– However, perhaps a male’s behavior
contributes to this as it brings forth the
disorder to a teacher’s attention more easily.
– Perhaps females can more readily
compensate
Etiology of Dyslexia
• Environment:
– Limited English vocabulary
• English as second language students.
– Difficulty understanding phonemics.
– Children of poverty
– Children with parents with low reading levels
– Students with speech or hearing impairments
Articulatory Problems
Categorized into subgroups:
1. Those with speech perception difficulties
2. Those with normal speech perception
•
•
•
Subjects asked to identify words that contrasted phonemes /s/
and /S/. In this test, a subgroup of articulation-disordered
children were unable to identify the test stimuli appropriately
(seat vs. sheet).
Subjects asked to identify words that contrasted the phonemes
/s/ and /theta/, In words sick and thick, and none of the
articulation-disordered children were able to identify these
words appropriately whereas children without disorder could.
Important to assess speech perception abilities prior to
initiating articulation therapy
Rvachew S & Jamieson DG. (1989). Perception of voiceless fricatives by children
with a functional articulation disorder. J Speech Hear Disord.; 54(2):193-208.
Reading Disorders
• Difficultly reading or understanding
material within a reading.
• Most have problems with their phonemic
(sound/symbol relationships) awareness
development.
– Have difficult time putting together letters to
make a sound.
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