Improvement of hemispatial neglect with cold-water calorics: an electrophysiological test of the arousal hypothesis of neglect

J Int Neuropsychol Soc. 1997 Jul;3(4):394-402.

Abstract

Introducing ice-water into the left ear of right-brain-damaged patients attenuates unilateral neglect symptoms. By examining EEG changes over each hemisphere during this procedure, we were able to test a hypothesis concerning the mechanism of cold-water calorics and the attention-arousal hypothesis of hemispatial neglect. We present a case study of an 83-year-old woman with a massive right-hemisphere CVA exhibiting severe hemispatial neglect. Caloric stimulation produced a leftward eye deviation to central position, and a temporary partial remission of neglect symptoms. Significant changes in EEG activation indicated a central mechanism associated with the regularization of eye gaze. Caloric stimulation also produced a significant interaction between EEG frequency band and hemisphere, indicating that while both hemispheres increased in cortical activation, the right hemisphere increase was significantly greater. This supports the activation-arousal hypothesis of neglect over the mutual inhibition model.

Publication types

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

MeSH terms

  • Aged
  • Aged, 80 and over
  • Arousal / physiology*
  • Auditory Perception / physiology*
  • Caloric Tests / psychology*
  • Cerebral Infarction / diagnostic imaging
  • Cerebral Infarction / psychology*
  • Cerebral Infarction / therapy*
  • Electroencephalography
  • Electrophysiology
  • Female
  • Humans
  • Hypothermia, Induced*
  • Tomography, X-Ray Computed
  • Water

Substances

  • Water