Dynamics and cortical distribution of neural responses to 2D and 3D motion in human

J Neurophysiol. 2014 Feb;111(3):533-43. doi: 10.1152/jn.00549.2013. Epub 2013 Nov 6.

Abstract

The perception of motion-in-depth is important for avoiding collisions and for the control of vergence eye-movements and other motor actions. Previous psychophysical studies have suggested that sensitivity to motion-in-depth has a lower temporal processing limit than the perception of lateral motion. The present study used functional MRI-informed EEG source-imaging to study the spatiotemporal properties of the responses to lateral motion and motion-in-depth in human visual cortex. Lateral motion and motion-in-depth displays comprised stimuli whose only difference was interocular phase: monocular oscillatory motion was either in-phase in the two eyes (lateral motion) or in antiphase (motion-in-depth). Spectral analysis was used to break the steady-state visually evoked potentials responses down into even and odd harmonic components within five functionally defined regions of interest: V1, V4, lateral occipital complex, V3A, and hMT+. We also characterized the responses within two anatomically defined regions: the inferior and superior parietal cortex. Even harmonic components dominated the evoked responses and were a factor of approximately two larger for lateral motion than motion-in-depth. These responses were slower for motion-in-depth and were largely independent of absolute disparity. In each of our regions of interest, responses at odd-harmonics were relatively small, but were larger for motion-in-depth than lateral motion, especially in parietal cortex, and depended on absolute disparity. Taken together, our results suggest a plausible neural basis for reduced psychophysical sensitivity to rapid motion-in-depth.

Keywords: 3D; high-density EEG; stereomotion; vision.

Publication types

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

MeSH terms

  • Adult
  • Aged
  • Brain Mapping*
  • Depth Perception*
  • Evoked Potentials, Visual*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Motion Perception*
  • Neurons / physiology*
  • Visual Cortex / cytology
  • Visual Cortex / physiology*