The parvocellular LGN provides a robust disynaptic input to the visual motion area MT

Neuron. 2006 Apr 20;50(2):319-27. doi: 10.1016/j.neuron.2006.03.019.

Abstract

Dorsal visual cortical areas are thought to be dominated by input from the magnocellular (M) visual pathway, with little or no parvocellular (P) contribution. These relationships are supported by a close correlation between the functional properties of these areas and the M pathway and by a lack of anatomical evidence for P input. Here we use rabies virus as a retrograde transynaptic tracer to show that the dorsal area MT receives strong input, via a single relay, from both M and P cells of the lateral geniculate nucleus. This surprising P input, likely relayed via layer 6 Meynert cells in primary visual cortex, can provide MT with sensitivity to a more complete range of spatial, temporal, and chromatic cues than the M pathway alone. These observations provide definitive evidence for P pathway input to MT and show that convergence of parallel visual pathways occurs in the dorsal stream.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Geniculate Bodies / anatomy & histology*
  • Geniculate Bodies / physiology
  • Macaca
  • Male
  • Motion Perception / physiology*
  • Neurons / cytology
  • Neurons / metabolism
  • Synapses / physiology
  • Visual Cortex / anatomy & histology*
  • Visual Cortex / physiology
  • Visual Pathways / anatomy & histology*
  • Visual Pathways / physiology