Tracing the timing of human analysis of motion and chromatic signals from occipital to temporo-parieto-occipital cortex: a transcranial magnetic stimulation study

Vision Res. 1998 Sep;38(17):2619-27. doi: 10.1016/s0042-6989(98)00025-x.

Abstract

In human visual analysis, the initial processing of motion and chromatic signals may be mediated by feed-forward pathways from striate cortex to segregated areas of extrastriate cortex. The time-course of occipital to temporo-parieto-occipital motion processing was unknown, as was the selectivity of the effect of transcranial magnetic stimulation (TMS) on motion processing. TMS delivered over occipital cortex degraded the discrimination of motion-defined form (MDF) in a discrete time window beginning 100-120 ms from the onset of the visual stimulus. Bilateral focal TMS delivered over the temporo-parieto-occipital junction (TPO) disrupted the discrimination of MDF in a time window beginning 20-40 ms later than the effect of TMS delivered over occipital cortex. Bilateral focal TMS delivered over TPO also degraded the discrimination of CDF, motion direction, and color.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Brain
  • Color Perception*
  • Humans
  • Middle Aged
  • Motion Perception*
  • Psychophysics
  • Time Factors
  • Transcranial Magnetic Stimulation / adverse effects*