Coherent alpha oscillations link current and future receptive fields during saccades

Proc Natl Acad Sci U S A. 2017 Jul 18;114(29):E5979-E5985. doi: 10.1073/pnas.1701672114. Epub 2017 Jul 3.

Abstract

Oscillations are ubiquitous in the brain, and they can powerfully influence neural coding. In particular, when oscillations at distinct sites are coherent, they provide a means of gating the flow of neural signals between different cortical regions. Coherent oscillations also occur within individual brain regions, although the purpose of this coherence is not well understood. Here, we report that within a single brain region, coherent alpha oscillations link stimulus representations as they change in space and time. Specifically, in primate cortical area V4, alpha coherence links sites that encode the retinal location of a visual stimulus before and after a saccade. These coherence changes exhibit properties similar to those of receptive field remapping, a phenomenon in which individual neurons change their receptive fields according to the metrics of each saccade. In particular, alpha coherence, like remapping, is highly dependent on the saccade vector and the spatial arrangement of current and future receptive fields. Moreover, although visual stimulation plays a modulatory role, it is neither necessary nor sufficient to elicit alpha coherence. Indeed, a similar pattern of coherence is observed even when saccades are made in darkness. Together, these results show that the pattern of alpha coherence across the retinotopic map in V4 matches many of the properties of receptive field remapping. Thus, oscillatory coherence might play a role in constructing the stable representation of visual space that is an essential aspect of conscious perception.

Keywords: V4; alpha frequency; communication through coherence; remapping; saccades.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Darkness
  • Female
  • Macaca fascicularis
  • Neurons / physiology
  • Photic Stimulation
  • Saccades / physiology*
  • Visual Cortex / physiology*