JN AJP: Lung Cellular and Molecular Physiology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
 QUICK SEARCH:   [advanced]


     


J Neurophysiol (November 26, 2008). doi:10.1152/jn.90843.2008
This Article
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
101/2/773    most recent
90843.2008v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Web of Science (5)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Chandrasekaran, C. F
Right arrow Articles by Ghazanfar, A. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Chandrasekaran, C. F
Right arrow Articles by Ghazanfar, A. A.
Submitted on August 1, 2008
Revised on November 19, 2008
Accepted on November 20, 2008

Different neural frequency bands integrate faces & voices differently in the superior temporal sulcus

Chandramouli F Chandrasekaran1 and Asif A. Ghazanfar1*

1 Princeton University

* To whom correspondence should be addressed. E-mail: asifg{at}princeton.edu.

The integration of auditory and visual information is required for the default mode of speech face-to-face communication. As revealed by fMRI and electrophysiological studies, the regions in and around the superior temporal sulcus (STS) are implicated in this process. To provide greater insights into the network-level dynamics of the STS during audiovisual integration, we used a macaque model system to analyze the different frequency bands of local field potential (LFP) responses to the auditory and visual components of vocalizations. These vocalizations (like human speech) have a natural time delay between the onset of visible mouth movements and the onset of the voice (the 'time-to-voice', or TTV). We show that the LFP responses to faces and voices elicit distinct bands of activity in the theta (4-8 Hz), alpha (8-14 Hz) and gamma (>40 Hz) frequency ranges. Along with single neuron responses, the gamma band activity was greater for face stimuli than voice stimuli. Surprisingly, the opposite was true for the low frequency bands-auditory responses were of a greater magnitude. Furthermore, gamma band responses in STS were sustained for dynamic faces, but not so for voices (the opposite is true for auditory cortex). These data suggest that visual and auditory stimuli are processed in fundamentally different ways in the STS. Finally, we show that the three bands integrate faces and voices differently: theta band activity showed weak multisensory behavior regardless of TTV, the alpha band activity was enhanced for calls with short TTVs, but show little integration for longer TTVs, and finally, the gamma band activity was consistently enhanced for all TTVs. These data demonstrate that LFP activity from the STS can be segregated into distinct frequency bands which integrate audiovisual communication signals in an independent manner. These different bands may reflect different spatial scales of network processing during face-to-face communication.




This article has been cited by other articles:


Home page
Proc. Natl. Acad. Sci. USAHome page
S. A. Steckenfinger and A. A. Ghazanfar
Monkey visual behavior falls into the uncanny valley
PNAS, October 27, 2009; 106(43): 18362 - 18366.
[Abstract] [Full Text] [PDF]


Home page
J. Neurosci.Home page
A. R. Powers III, A. R. Hillock, and M. T. Wallace
Perceptual Training Narrows the Temporal Window of Multisensory Binding
J. Neurosci., September 30, 2009; 29(39): 12265 - 12274.
[Abstract] [Full Text] [PDF]


Home page
J. Neurosci.Home page
J. Jacobs and M. J. Kahana
Neural Representations of Individual Stimuli in Humans Revealed by Gamma-Band Electrocorticographic Activity
J. Neurosci., August 19, 2009; 29(33): 10203 - 10214.
[Abstract] [Full Text] [PDF]




HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
Visit Other APS Journals Online
Copyright © 2008 by the The American Physiological Society.