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Published on: August 12, 2019
Psychic tonus, body schema and the parietal lobes: a multiple lesion case analysis
C M J Braun1, S Desjardins, S Gaudelet
1Centre de Neurosciences de la Cognition and Department of Psychology, Université du Québec à Montréal, Canada. Braun.Claude@UQAM.CA
Behavioural Neurology
|June 1, 2007
Summary
The psychic tonus model suggests hemisphere roles in body schema. Right hemisphere lesions link to positive body schema disturbances, while left hemisphere lesions correlate with negative disturbances.
Area of Science:
- Neuroscience
- Cognitive Psychology
- Neurology
Background:
- The psychic tonus model posits hemispheric specialization: left hemisphere as "booster," right as "dampener."
- Previous research supported this model for various functions like psychomotor baseline, libido, and perception.
Purpose of the Study:
- To test the psychic tonus model's predictions regarding hemispheric specialization in body schema representation.
- To investigate the relationship between unilateral parietal lesions and disturbances in body schema.
Main Methods:
- Literature analysis of 25 patients with positive body schema disturbance (somatoparaphrenia) and 37 with negative disturbance (autotopagnosia/Gerstmann's syndrome).
- Correlation of lesion laterality (left vs. right hemisphere) with specific body schema disturbance types.
Main Results:
- Patients with positive body schema disturbance were significantly more likely to have right hemisphere lesions.
- Patients with negative body schema disturbance were significantly more likely to have left hemisphere lesions.
Conclusions:
- The psychic tonus model is extended to include the tonus of body schema representation within the parietal lobes.
- Hemispheric specialization influences the experience and representation of one's own body.
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