Switch to
| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
1
|
| pubmed:dateCreated |
1984-4-6
|
| pubmed:abstractText |
Auditory brainstem responses (ABR) evoked by clicks allow a threshold evaluation for the high-frequency range (2-4 kHz) but not for middle and low frequencies (0.5-1 kHz). In 19 normally hearing subjects aged between 24 and 40 years. ABRs have been recorded using clicks and 0.5- and 1-kHz tone pips, with durations of 6 and 3 ms, respectively, and rise-decay times of 3 and 1.5 ms. The input signal was filtered by a passband filter of 20-5 000 Hz. Parameters of tracings elicited by the different kinds of stimuli are compared. Tone-pip ABR morphology does not show the conventional seven peaks but a single large vertex-positive wave. On the ascending branch high-frequency potentials, probably corresponding to the I, II, III and IV-V click-evoked peaks, were visible in some cases, but they rapidly disappeared as the stimulus intensity was decreased. Their 2.3-3 ms greater mean latency values are presumably related to the rise times of the stimuli employed. In terms of bioelectric generators, this large vertex-positive peak probably corresponds to the Jewett V wave. It probably represents a generalized asynchronous dendritic activity. Thus it is possible to obtain ABRs to middle- and low-frequency stimuli. Mean amplitude values of the slow wave are considerably higher than those of the Jewett V wave, but standard deviations are also larger. The positive wave has been identified in response to 1-kHz tone pips in 100% of cases at 30 dB nHL and in 52% of cases at 20 dB, while for 0.5-kHz tone pips in 73.7% of cases at 30 dB and in 57% at 20 dB. On the whole the threshold is located between 15 and 30 dB nHL.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:status |
MEDLINE
|
| pubmed:issn |
0020-6091
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
23
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
75-84
|
| pubmed:dateRevised |
2004-11-17
|
| pubmed:meshHeading |
pubmed-meshheading:6704061-Acoustic Stimulation,
pubmed-meshheading:6704061-Adult,
pubmed-meshheading:6704061-Audiometry,
pubmed-meshheading:6704061-Audiometry, Evoked Response,
pubmed-meshheading:6704061-Auditory Threshold,
pubmed-meshheading:6704061-Brain Stem,
pubmed-meshheading:6704061-Evoked Potentials, Auditory,
pubmed-meshheading:6704061-Humans
|
| pubmed:year |
1984
|
| pubmed:articleTitle |
Auditory brainstem responses to middle- and low-frequency tone pips.
|
| pubmed:publicationType |
Journal Article
|