Improvement of hemispatial neglect with cold-water calorics: an electrophysiological test of the arousal hypothesis of neglect.
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.
Storrie-Baker
H J
HJ
Department of Psychology, West Park Hospital, Toronto, Ontario, Canada.
Segalowitz
S J
SJ
Black
S E
SE
McLean
J A
JA
Sullivan
N
N
D000368:Aged; D000369:Aged, 80 and over; D001143:Arousal / Q000502:physiology*; D001307:Auditory Perception / Q000502:physiology*; D002150:Caloric Tests / Q000523:psychology*; D002544:Cerebral Infarction / Q000000981:diagnostic imaging / Q000523:psychology* / Q000628:therapy*; D004569:Electroencephalography; D004594:Electrophysiology; D005260:Female; D006801:Humans; D007036:Hypothermia, Induced; D014057:Tomography, X-Ray Computed; D014867:Water
D014867:Water