Model-free detection of synchrony in neuronal spike trains, with an application to primate somatosensory cortex

Synchronized neuronal firing has been reported in many neural systems and m ay play a role in the representation of sensory stimuli and the modificatio n of sensory representations by both experience and attention. In this repo rt we describe a bootstrap procedure for computing the statistical signific ance of changes in the degree of synchrony and apply it to recordings from the second somatosensory (SII) cortex of Macaques performing tactile and vi sual discrimination tasks. A majority (68%) of neuron pairs in Sn fire sync hronously in response to a tactile stimulus. In a fraction of those pairs ( 17.5%), the degree of synchrony covaries with the focus of attention. (C) 2 000 Elsevier Science B.V. All rights reserved.