Dynamic properties of thalamic neurons for vision

Prog Brain Res. 2005:149:83-90. doi: 10.1016/S0079-6123(05)49007-X.

Abstract

A striking property of neurons in the lateral geniculate nucleus (LGN) of the thalamus is the ability to dynamically filter and transform the temporal structure of their retinal spike input. In particular, LGN neurons respond to visual stimuli with either burst spike responses or tonic spike responses. While much is known from in vitro studies about the cellular mechanisms that underlie burst and tonic spikes, relatively little is known about the sensory stimuli that evoke these two categories of spikes. This review examines recent progress that has been made towards understanding the spatiotemporal properties of visual stimuli that evoke burst and tonic spikes. Using white-noise stimuli and reverse-correlation analysis, results show that burst and tonic spikes carry similar, but distinct, information to cortex. Compared to tonic spikes, burst spikes (1) occur with a shorter latency between stimulus and response, (2) have a greater dependence on stimuli with transitions from suppressive to preferred states, and (3) prefer stimuli that provide increased drive to the receptive field center and even greater increased drive to the receptive field surround. These results are discussed with an emphasis placed on relating the cellular constraints for burst and tonic activity with the functional properties of the early visual pathway during sensory processing.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Action Potentials / physiology*
  • Animals
  • Geniculate Bodies / cytology
  • Geniculate Bodies / physiology*
  • Humans
  • Neurons / cytology
  • Neurons / physiology*
  • Reaction Time / physiology
  • Synaptic Transmission / physiology
  • Visual Fields / physiology
  • Visual Pathways / physiology
  • Visual Perception / physiology*