Categorical and coordinate spatial relations: fMRI evidence for hemispheric specialization

Neuroreport. 1999 Apr 26;10(6):1373-8. doi: 10.1097/00001756-199904260-00040.


Functional magnetic resonance imaging (fMRI) was applied to determine the involvement of the angular gyri in the processing of categorical and coordinate spatial relations. In a categorical task, subjects were asked to judge whether a dot was presented above or below a horizontal line. In a coordinate task, they were asked to judge whether or not the distance between the dot and the bar was within a reference distance. Results showed stronger activation of the left than of the right angular gyrus in the categorical task, and stronger activation, initially, of the right than of the left angular gyrus in the coordinate task. In addition, in the latter task, the involvement of the right angular gyrus decreased with practice while that of the left angular gyrus increased. These results are interpreted in terms of the development of new categorical representations with practice in the coordinate task.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Brain Mapping*
  • Functional Laterality / physiology*
  • Humans
  • Magnetic Resonance Imaging / methods
  • Male
  • Parietal Lobe / physiology*
  • Photic Stimulation
  • Psychomotor Performance / physiology*
  • Space Perception / physiology*
  • Visual Fields / physiology