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Human auditory cortex responses to rising versus falling glides.

P J Pardo·M Sams
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Abstract

A 24-channel SQUID magnetometer was used to record signals from the right auditory cortex to tone glides with 16 different centre frequencies (ranging from 0.5 to 2 kHz), sweeping over one octave. The stimulus sequence, presented with an interstimulus onset interval of 0.6 s, consisted of infrequent 'deviant' rising (falling) glides and frequent 'standard' falling (rising) glides; the rising glides were identical to the falling glides but presented in the reverse direction. Deviant glides elicited significantly larger responses than standards at a latency of about 100 ms. This amplitude difference presumably arises from a mismatch response to the deviants. These results suggest that the auditory cortex extracts the direction of frequency transition even when the stimuli do not contain same frequencies.

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Acoustic StimulationAdultAuditory CortexElectroencephalographyFemaleHumansMagnetoencephalographyMaleJournal ArticleResearch Support, Non-U.S. Gov't

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P J Pardo, M Sams. 1993-09-03. Human auditory cortex responses to rising versus falling glides.. https://doi.org/10.1016/0304-3940(93)90794-l

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