Accuracy of saccades to remembered targets as a function of body orientation in space.


Journal Article

A vertical asymmetry in memory-guided saccadic eye movements has been previously demonstrated in humans and in rhesus monkeys. In the upright orientation, saccades generally land several degrees above the target. The origin of this asymmetry has remained unknown. In this study, we investigated whether the asymmetry in memory saccades is dependent on body orientation in space. Thus animals performed memory saccades in four different body orientations: upright, left-side-down (LSD), right-side-down (RSD), and supine. Data in all three rhesus monkeys confirm previous observations regarding a significant upward vertical asymmetry. Saccade errors made from LSD and RSD postures were partitioned into components made along the axis of gravity and along the vertical body axis. Up/down asymmetry persisted only in body coordinates but not in gravity coordinates. However, this asymmetry was generally reduced in tilted positions. Therefore the upward bias seen in memory saccades is egocentric although orientation in space might play a modulatory role.

Full Text

Cited Authors

  • Vogelstein, JT; Snyder, LH; Angelaki, DE

Published Date

  • July 2003

Published In

Volume / Issue

  • 90 / 1

Start / End Page

  • 521 - 524

PubMed ID

  • 12843314

Pubmed Central ID

  • 12843314

Electronic International Standard Serial Number (EISSN)

  • 1522-1598

International Standard Serial Number (ISSN)

  • 0022-3077

Digital Object Identifier (DOI)

  • 10.1152/jn.00141.2003


  • eng