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Left hemisphere involvement in left spatial neglect from right-sided lesions
Brain : a Journal of Neurology
|March 1, 1984
Summary
The left hemisphere possesses awareness of the left body and space, challenging neglect syndrome views. This suggests right hemisphere damage causes neglect by preventing left hemisphere compensation.
Area of Science:
- Neuroscience
- Cognitive Psychology
- Neurology
Background:
- Unilateral neglect syndrome is typically attributed to right hemisphere lesions causing left-sided unawareness.
- This view assumes the left hemisphere lacks awareness for its contralateral side.
Purpose of the Study:
- To investigate the awareness capabilities of the isolated left hemisphere in patients with complete forebrain commissurotomy.
- To re-evaluate the underlying mechanisms of unilateral neglect syndrome.
Main Methods:
- Administered lateralized tests for left hemineglect to three split-brain patients.
- Assessed awareness for the left side of the body and extrapersonal space in the disconnected left hemisphere.
Main Results:
- The disconnected left hemisphere demonstrated significant awareness of the left body and space.
- This awareness was considerably greater than predicted by unilateral lesion data.
Conclusions:
- The independent left hemisphere possesses cognitive mechanisms to prevent neglect syndrome.
- The explanation for unilateral neglect must address the failure of left hemisphere compensation following right-sided lesions.
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