Phase synchrony among neuronal oscillations in the human cortex

Palva, J. M. , Palva, S. and Kaila, K. (2005) Phase synchrony among neuronal oscillations in the human cortex. Journal of Neuroscience, 25(15), pp. 3962-3972. (doi: 10.1523/JNEUROSCI.4250-04.2005) (PMID:15829648)

Abstract

Synchronization of neuronal activity, often associated with network oscillations, is thought to provide a means for integrating anatomically distributed processing in the brain. Neuronal processing, however, involves simultaneous oscillations in various frequency bands. The mechanisms involved in the integration of such spectrally distributed processing have remained enigmatic. We demonstrate, using magnetoencephalography, that robust cross-frequency phase synchrony is present in the human cortex among oscillations with frequencies from 3 to 80 Hz. Continuous mental arithmetic tasks demanding the retention and summation of items in the working memory enhanced the cross-frequency phase synchrony among α (∼10 Hz), β (∼20 Hz), and γ (∼30-40 Hz) oscillations. These tasks also enhanced the “classical” within-frequency synchrony in these frequency bands, but the spatial patterns of α, β, and γ synchronies were distinct and, furthermore, separate from the patterns of cross-frequency phase synchrony. Interestingly, an increase in task load resulted in an enhancement of phase synchrony that was most prominent between γ- and α-band oscillations. These data indicate that cross-frequency phase synchrony is a salient characteristic of ongoing activity in the human cortex and that it is modulated by cognitive task demands. The enhancement of cross-frequency phase synchrony among functionally and spatially distinct networks during mental arithmetic tasks posits it as a candidate mechanism for the integration of spectrally distributed processing.

• Item Type: Articles
• Additional Information: This work was supported by the Academy of Finland, the Sigrid Juselius Foundation, the Foundation for the Advancement of Technology, the Oskar Öflund Foundation, and the Ella and Georg Ehrnrooth Foundation.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Palva, Professor Satu and Palva, Professor Matias
• Authors: Palva, J. M., Palva, S., and Kaila, K.
• College/School: College of Medical Veterinary and Life Sciences > School of Psychology & Neuroscience
• Journal Name: Journal of Neuroscience
• Publisher: Society for Neuroscience
• ISSN: 0270-6474
• ISSN (Online): 1529-2401