Global perception in simultanagnosia is not as simple as a game of connect-the-dots

Vision Res. 2009 Jul;49(14):1901-8. doi: 10.1016/j.visres.2009.05.002. Epub 2009 May 19.


Simultanagnosia is a neuropsychological disorder characterized by a restriction of visuospatial attention. In addition, patients are able to identify local elements of a scene, but not the global whole. This may be due to a failure to scan and assemble local elements into a global whole (i.e. connect-the-dots). We monitored the eye movements of a simultanagnosic patient while she identified local and global elements of hierarchical letters. Scanning each local element was not necessary, nor sufficient, for successful global level identification. Our results argue against a connect-the-dots strategy of global identification and suggest that residual global processing may be occurring.

Publication types

  • Case Reports
  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Agnosia / pathology
  • Agnosia / psychology*
  • Attention*
  • Case-Control Studies
  • Eye Movements / physiology*
  • Female
  • Humans
  • Magnetic Resonance Imaging
  • Middle Aged
  • Neuropsychological Tests
  • Pattern Recognition, Visual / physiology*
  • Space Perception / physiology*
  • Visual Pathways / physiology