Term
History:
-In ___ German physiologist Emil DuBois-Reymond describes nerve ___ ___
-In ___ British scientist Richard Caton describes ___ activity in the brain
-In ___ the cathode ray tube oscilloscope was invented, allowing direct observation of ___ activity in the brain |
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Definition
| 1848; action potentials; 1875; electrical; 1922; electrical |
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Term
More History:
-In ___ German physician Hans Berger publishes ___ recorded from human brain activity
-In ___, Ernest Glen Wever and Charles Bray describe cochlear ___ recorded in cats
-In ___ Hallowell Davis publishes first description of electrical ___ to auditory stimuli in the EEG, including the __________ |
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Definition
| 1929; EEGs; 1930; microphonic; 1939; responses; auditory late response (ALR) |
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Term
-Electrocochleography was first described in 1930
-Components (cochlear ___ and compound ___ ___) identified by Saul and Davis (1932) |
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Definition
| microphonic; action potential |
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Term
-As early as the 1940s, otologist Julius Lempert and physiologists Ernest Wever and Merle Lawrence had (1) located the ___ ___ for ECochG recording and (2) predicted its ___ ___, including its value for intra-operative monitoring
-Our observations thus confirm those previously reported that the ___ window membrane is the only suitable location for the electrode…Here we envisage [the electrocochleogram] being used both for general ___ and for ___ guidance. |
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Definition
| optimal site; clinical utility; round; diagnosis; surgical |
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Term
History:
-In 1951, ___ ___ described by British physiologist G.D. Dawson –with repeated stimulus presentation, random noise could be ___ and effectively ___. Note that this is ____
-In ___ Dawson introduces the first electronic response averaging device– an analog device that could average across ___ time points
-In the late 1950s, the first digital computer averaging devices appear |
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Definition
| signal averaging; averaged; reduced; pre-computer; 1954; 124 |
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Term
History:
-In 1958, Daniel Geisler, a Ph.D. student at M.I.T., publishes the first description of the __________ in humans
-In 1964-1965, ___ ___ is independently
discovered and described by Hallowell Davis and a UK/US consortium led by Samuel Sutton, M. Braren, Joseph Zubin, and E. Roy John* |
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Definition
auditory middle latency response (AMLR); 300 response
[image] |
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Term
-In ___ Israeli scientists Harvey Sohmer and Moshe Feinmesser publish a paper titled “Cochlear action potentials recorded from the external ear in man” in Annals of Otology, Rhinology, and Laryngology
-Published waveforms recognizable as ___
-Research focus was on ECochG only, but Sohmer and Feinmesser made note of “succeeding negative peaks, which are also observed in recordings in animals, may be due to ___ firing of auditory nerve fibers… or may be due to the ___ of neurons in brainstem auditory nuclei” |
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Definition
1967; ABR; repetitive; discharge
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Term
What is this article known for?
Jewett, D. and Williston J. (1971). Auditory evoked far fields averaged from the scalp of humans. Brain 4, 681-696. |
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Definition
First description of ABR
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Term
-AER had developments in the ___
-____ electrodes
–___ ___ of responses. Made ____ possible.
– Improvements in waveform ___, ___ precision, ___ analysis
– Advances in understanding of waveform ___
– First descriptions of the _____________, development of instrumentation for measurement by Picton and others |
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Definition
| 1980s; Non-invasive; Tape recording; re-analysis; resolution; filtering online; generators; auditory steady-state response (ASSR) |
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Term
| Auditory evoked potential elicited with amplitude modulated tones |
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Definition
| Auditory Steady State Response (ASSR) |
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Term
ASSR:
-___ potential following the envelope of complex stimulus
-Used to predict hearing sensitivity: ___ specific, objective, and can be used across a wide ___ range, with patient ___ or ___, and with wide range of ___ ___ |
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Definition
| Neural; Frequency; age; asleep; alert; hearing loss. |
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Term
-Limitation of ALR and AMLR: requires patient be ___
-Limitation of ABR: limited ___- specific information, insensitive to hearing sensitivity above about ___ dB HL |
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Definition
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Term
What does this describe?
"A series of 5-7 peaks rising from the VIII nerve and brainstem
structures and occurring within an epoch of 10 msec from the
onset of a stimulus sound" |
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Definition
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Term
| What are the wave generators of the ABR? |
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Definition
1-distal 8th nerve
2-proximal 8th nerve
3-caudal brainstem (CN)
4-SOC or CN (Not sure)
5-Lateral lemniscus (at contralateral IC)
6 and 7-Medial geniculate (not sure) |
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Term
ABR audiometry – threshold estimation:
Objective estimate of ___ ___ using measurement of
ABR in response to click or tone burst stimuli |
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Definition
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Term
ABR Utility: Identification of retrocochlear pathology
-Prolonged absolute __ latency
– Interaural difference in absolute __ latency
– Prolonged ___, ___, ___ latency
– Interaural difference in ___ latency
–___ response |
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Definition
| V; V; I-III, I-V, III-V; I-V; Absent |
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Term
| ABR is also used for ___ ___ screening and to monitor changes in ____ status of peripheral and central nervous system during surgery |
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Definition
| newborn hearing; neurophysiologic |
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Term
| What instrumentation do you need to elicit a response for the AER? What about for measuring the response? |
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Definition
Eliciting response: signal generator and transducers.
Measuring the response: electrodes, amplification, filtering, and averaging |
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Term
-AERs are optimally induced using very ___ stimuli (___)
-Clicks (~___ microsec)-___ spectrum, ___ range of activation on the basilar membrane
-Tone bursts-___ spectrum, ___ range of activation on the basilar membrane |
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Definition
| brief; transients; 100; broad; wide; narrow; narrow |
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Term
Signal Parameters:
___-the sum of the rise time, fall time, and plateau |
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Definition
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Term
Signal Parameters: Duration
-Most common duration for tone bursts: __ cycles rise time, __
cycles fall time, no plateau. Duration for tone-burst stimulation is, therefore, ___ specific
– Click stimuli are held at a ___ duration. Usually __ msec |
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Definition
| 2; 2; frequency; constant; .1 |
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Term
Signal Parameters-Intensity:
-General principle: higher intensity stimuli → ___ response
latencies → ___ response amplitudes
-Unit measure: dB normal hearing level (nHL): dB relative to
___ ___ hearing threshold level for the stimulus |
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Definition
| shorter; higher; normal behavioral |
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Term
Signal Parameters: Rate
-Controlled by the ___
– Different rates are most appropriate for different AERs
-Most appropriate rate varies as a function of the ___ of the test and subject ____ (age, body temperature), sedation, etc. |
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Definition
| tester; goal; characteristics |
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Term
Signal Parameters:
-Condensations (___)
-Rarefaction (___)
-Critical for ___ stimuli; not a major factor for ______
-Displacement appears to be ___ for rarefaction clicks than for condensation clicks. Therefore, ___ response amplitude
-Rarefaction click initially ___ cochlear hair cells, producing shorter response latency |
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Definition
| positive; negative; click; tone bursts; greater; greater; depolarizes |
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Term
-condensation pushes TM ___ and scala media is pushed ___
-Rarefaction is the opposite. Pushes TM ___ and pushes scala media ___ |
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Definition
| inward; downward; outward; upward |
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Term
| Rarefaction displaces basilar membrane ___ |
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Definition
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Term
-The CE-Chirp is designed to maximize wave __
-Uses ___ ___ to compensate for differential travel time of various frequency components of a broadband stimulus
-Ex: since lower frequency sounds must travel further (toward cochlear apex) before they cause max displacement,they are introduced ___ |
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Definition
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Term
| What kind of transducers were used until the early 1990s? |
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Definition
| TDH-39 or -49 earphone with MX41/AR cushion |
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Term
Problems with TDH-39 or -49:
-Creates an electromagnetic field which produces stimulus ___
-Occludes but does not enclose the ear, allowing leakage of ___-frequency energy at the jawline
-___ |
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Definition
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Term
| What are the best and most common transducer for most AERs? |
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Definition
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Term
| What are some advantages of using inserts for AERs specifically? |
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Definition
| Reduced transducer ringing and reduced stimulus artifact |
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Term
Signal Parameters: Transducer
-The bone oscillator is used for assessment of ___, ___ children, and other ___-to-test patients. Calculation of ___ ___ from air- and bone-elicited ABR audiograms
-As with audiometric testing, proper ___ and ___ can affect response |
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Definition
| infants; young;difficult; air-bone gap; placement; force |
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Term
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Definition
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