Emergence of un-correlated common-mode oscillations in the sensory cortex

Simultaneous EEG recordings from various cortical areas indicate the presen ce of common-mode, spatially coherent oscillations. These oscillations are characterized by a common wave form with a spatially distributed pattern of amplitude modulation (AM). We observe highly reproducible AM patterns acro ss spatially separated channels within various areas, yet the temporal corr elations between the channels are low. In the framework of the present rese arch, a nonlinear, spatially distributed dynamical model of neuronal popula tions (KIII) is used for the interpretation of the observed spatial coheren ce. The theoretical findings are in good agreement with experiments perform ed with chronically implanted rabbits. (C) 2001 Elsevier Science B,V. All r ights reserved.