Influence of stimulus polarity on far-field auditory-evoked electrical responses in the chick.
The effects of inverting click phase on far-field peripheral and brainstem auditory-evoked responses (PBARs) were examined in 8 White Leghorn chicks of age 3 wks. Significant latency differences occurred in all major positive peaks (Pla, P2a peripheral; P3a central) in response to rarefaction vs condensation clicks of equal intensity, with condensation clicks producing the shortest latencies (latency differences: Pla = 0.374, P2a = 0.372 and P3a = 0.352 msec, p less than .001). The mean latency shift corresponds to an equivalent sine wave frequency of approximately 1360 c/s, a value close to the spectral peak energy of the click. No differences in interpeak latency values were found nor any significant amplitude effects.
Department of Animal Science, University of Nebraska, Lincoln.
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Brown-Borg
M M
MM
Beck
T A
TA
Jones
D000161:Acoustic Stimulation; D000818:Animals; D001933:Brain Stem / Q000502:physiology; D002645:Chickens / Q000502:physiology*; D005072:Evoked Potentials, Auditory; D007837:Latency Period, Psychological