Semester 2.1 Praxis Comps
Differential Diagnosis
Auditory Pathologies
Instrumentation
Amplification I
Auditory Pathologies
Instrumentation
Amplification I
Terms
undefined, object
copy deck
- prevalence
- number of cases of a disease at a given time (usually per 100,000)
- incidence
- number of new cases in the outbreak of a disease for a specific period of time
- sensitivity
- =true positive/(true positive + false negative) Correctly identifies those with disease
- specificity
- =true negative/(true negative + false positive) Correctly identifies those without the disease
- tests for malingering
- Stenger (unilateral) immittance evoked potentials ascending/descending SRT/PTA agreement
- SISI results
- people with cochlear losses can perceive 1 dB intensity increases while normals can not (esp. at high frequencies)
- tone decay
- reduction in the ability to hear a sustained tone; results measured in dB (dB at which there is 0 decay minus threshold dB)
- tone decay in cochlear losses
- 15-25 dB
- tone decay in retrocochlear losses
- >=30-35 dB
- Rainville mixed/conductive result
- BC masking shifts threshold
- William Brownell
- discovered hair cell motility
- David Kemp
- first to describe OAEs
- Bekesy
- traveling wave theory
- Helmholtz
- place theory
- Gold
- resonator theory
- Jewett and Williston
- seminal paper on ABR
- dB difference above noise floor for OAE to be present
- 6 dB
- OAEs absent when thresholds are > ___ dB
- 40-50 or less
- typical level of OAEs
- in the 2.5-8.5 dB SPL range
- middle ear causes for absent OAEs
- negative pressure large TM perf PE tubes sometimes otitis media otosclerosis
- TEOAE stimulus level
- around 80-85 dB SPL
- TEOAE stability parameter measures...
- reflects changes in stimulus intensity
- depolarization of OHCs causes them to (shorten/lengthen)
- shorten
- hyperpolarization of OHC causes them to (shorten/lengthen)
- lengthen
- 3 major structures of the brainstem
- pons, midbrain, medulla oblongata
- location of cochlear nucleus
- on surface of brainstem at junction of pons and medulla
- OAE suppression efferents come from the...
- olivo cochlear bundle (SOC)
- lowest structure in brainstem to receive binaural input
- superior olivary complex
- largest auditory structure in the brainstem; it is binaurally activated and plays a role in localization; it is probably responsible for Wave V
- inferior colliculus
- main function of brainstem in general
- autonomic functions (heart rate, digestion, breathing...)
- Trigeminal CN V functions
- chewing, face & mouth touch/pain
- Facial CN VII functions
- controls most facial expressions
- Glossopharyngeal CN IX functions
- taste
- Trochlear CN IV
- turns eye downward and laterally
- typical frequency for acoustic reflex decay
- 0.5 or 1 kHz
- level for acoustic reflex decay
- 10 dB > AR threshold
- AR decay positive result
- if response falls to < 50% of initial magnitude before 10 sec.
- sensitivity of acoustic reflex decay
- 85-95%
- ABR Wave I generator
- distal portion of 8th nerve
- ABR wave III generator
- cochlear nucleus
- ABR Wave V generator
- lateral lemniscus
- When ABR becomes adult-like
- 18 months
- typical analysis time for ABR
- 15-20 msec
- typical ABR filter
- 100-3000 Hz
- conductive HL ABR
- all latencies shifted to later; latency-intensity function parallel to normal curve but longer
- Wave V latency with clicks for high frequency losses
- latency is increased
- most common 8th nerve tumor
- schwannoma (benign)
- latency for wave V 20 dB click in 3-6 month olds
- 8.72 +/- 0.53 ms
- latency for wave V 80 dB click in 3-6 month olds
- 6.25 +/- 0.32 ms
- transducer
- changes energy from one form to another
- Leq, level equivalent
- level measured over time using a 3 dB exchange rate
- Lav, Level average
- level measured over time using an exchange rate other than 3, 4, 5
- current ANSI audiometer standard
- S3.6-204
- coupler used for TDH calibration
- 6cc coupler with 500 g weight
- A-weighting corresponds to human response at ___ dB HL
- 40 dB
- OSHA standard for allowable exposure time to 90 decibels
- 8 hours