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Evaluation of Hemisphere Lateralization with Bilateral Local Field Potential Recording in Secondary Motor Cortex of Mice
Published on: July 31, 2019
Laterality effects in schizophrenia and bipolar disorder
Marcella Bellani1, Carlo A Marzi, Silvia Savazzi
1Inter-University Center for Behavioural Neurosciences, University of Verona, Verona, Italy.
Experimental Brain Research
|October 2, 2009
Summary
Schizophrenia patients show slowed right-hand responses, unlike bipolar disorder patients, suggesting distinct left-hemisphere processing impairments. Both schizophrenia and bipolar disorder patients maintain normal interhemispheric transmission despite callosal abnormalities.
Area of Science:
- Neuroscience
- Psychiatry
- Cognitive Psychology
Background:
- Major psychoses like schizophrenia and bipolar disorder are linked to cerebral structural abnormalities and corpus callosum alterations.
- Understanding hemispheric differences and interhemispheric communication is crucial for differentiating these conditions.
Purpose of the Study:
- To directly compare hemispheric differences and callosal interhemispheric transmission (IT) in schizophrenia (SCZ) and bipolar disorder (BD).
- To investigate potential neurobiological distinctions between SCZ and BD through functional assessments.
Main Methods:
- Utilized the Poffenberger paradigm with lateralized visual stimuli to assess manual reaction time (RT) in SCZ patients, BD patients, and controls.
- Measured both laterality effects (hemispheric differences) and interhemispheric transmission (IT) time during a simple manual RT task.
Main Results:
- Schizophrenia patients exhibited an overall slowing of right-hand responses, not observed in bipolar disorder patients or controls.
- Interhemispheric transmission (IT) time was comparable across SCZ patients, BD patients, and controls.
- A selective impairment in left-hemispheric intrahemispheric processing was identified exclusively in SCZ patients.
Conclusions:
- Both schizophrenia and bipolar disorder patients demonstrate normal interhemispheric transmission of visuomotor information, despite underlying callosal abnormalities.
- The observed impairment in left-hemispheric intrahemispheric processing in schizophrenia patients, but not bipolar disorder patients, offers a key insight into the distinct pathogenetic mechanisms of these major psychoses.
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