Polar-angle representation of saccadic eye movements in human superior colliculus

Neuroimage. 2018 May 1:171:199-208. doi: 10.1016/j.neuroimage.2017.12.080. Epub 2017 Dec 30.

Abstract

The superior colliculus (SC) is a layered midbrain structure involved in directing both head and eye movements and coordinating visual attention. Although a retinotopic organization for the mediation of saccadic eye-movements has been shown in monkey SC, in human SC the topography of saccades has not been confirmed. Here, a novel experimental paradigm was performed by five participants (one female) while high-resolution (1.2-mm) functional magnetic resonance imaging was used to measure activity evoked by saccadic eye movements within human SC. Results provide three critical observations about the topography of the SC: (1) saccades along the superior-inferior visual axis are mapped across the medial-lateral anatomy of the SC; (2) the saccadic eye-movement representation is in register with the retinotopic organization of visual stimulation; and (3) activity evoked by saccades occurs deeper within SC than that evoked by visual stimulation. These approaches lay the foundation for studying the organization of human subcortical - and enhanced cortical mapping - of eye-movement mechanisms.

Keywords: Attention; Saccades; Subcortical vision; Superior colliculus; Topography; fMRI.

Publication types

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

MeSH terms

  • Attention / physiology*
  • Brain Mapping / methods*
  • Female
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Photic Stimulation
  • Saccades / physiology*
  • Superior Colliculi / physiology*
  • Visual Perception / physiology