Rate and filter effects on the developing middle-latency response.

N Kraus; D I Smith; T McGee

doi:10.3109/00206098709081554

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Rate and filter effects on the developing middle-latency response.

N Kraus·D I Smith·T McGee

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Abstract

Auditory middle-latency responses (MLRs) were obtained from 71 unanesthetized gerbils ranging in age from 10 to greater than 90 days. Effects of age, stimulation rate, high- and lowpass filter settings and filter slope were examined. MLR amplitude decreased significantly with increased stimulation rate at all ages, at rates up to 40/s. The detection of MLR waves (presence or absence) varied inversely with the rate of stimulation only in immature subjects. The amplitude of waves B (15 ms) and C (25 ms) was significantly larger with a highpass filter setting of 3 Hz as compared to 10 and 30 Hz. This effect was significantly more pronounced in developing animals as compared to adults. MLR amplitude was greater with a filter slope of 6 dB/octave as compared to 48 dB/octave, (10-2,000 Hz) and this effect was also significantly greater in developing animals than in adults. There was no interaction between lowpass filter setting and age (100 vs. 2,000 Hz). A prominent positive wave occurring at approximately 50 ms was present in the 48 dB/octave condition although it was not observed with 6 dB/octave filtering. The clinical use of the MLR requires a better understanding of the effects of stimulus and recording procedures on the response, and how they vary as a function of subject age.

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Aging Animals Auditory Perception Brain Stem Electroencephalography Evoked Potentials, Auditory Gerbillinae Pitch Perception Reaction Time Journal Article Research Support, U.S. Gov't, P.H.S.

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N Kraus, D I Smith, T McGee. 1987. Rate and filter effects on the developing middle-latency response.. https://doi.org/10.3109/00206098709081554

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