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Title: Cortical responses time-locked to continuous speech in the high-gamma band depend on selective attention
Auditory cortical responses to speech obtained by magnetoencephalography (MEG) show robust speech tracking to the speaker's fundamental frequency in the high-gamma band (70–200 Hz), but little is currently known about whether such responses depend on the focus of selective attention. In this study 22 human subjects listened to concurrent, fixed-rate, speech from male and female speakers, and were asked to selectively attend to one speaker at a time, while their neural responses were recorded with MEG. The male speaker's pitch range coincided with the lower range of the high-gamma band, whereas the female speaker's higher pitch range had much less overlap, and only at the upper end of the high-gamma band. Neural responses were analyzed using the temporal response function (TRF) framework. As expected, the responses demonstrate robust speech tracking of the fundamental frequency in the high-gamma band, but only to the male's speech, with a peak latency of ~40 ms. Critically, the response magnitude depends on selective attention: the response to the male speech is significantly greater when male speech is attended than when it is not attended, under acoustically identical conditions. This is a clear demonstration that even very early cortical auditory responses are influenced by top-down, cognitive, neural processing mechanisms.  more » « less
Award ID(s):
1734892
NSF-PAR ID:
10496143
Author(s) / Creator(s):
; ;
Publisher / Repository:
Frontiers
Date Published:
Journal Name:
Frontiers in Neuroscience
Volume:
17
ISSN:
1662-453X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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