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Published on: August 1, 2018
Visual-manual exploration and posterior parietal cortex in humans
Leighton B N Hinkley1, Leah A Krubitzer, Jeff Padberg
1Center for Neuroscience, University of California, Davis, Davis, CA 95616, USA.
Journal of Neurophysiology
|October 9, 2009
Summary
This study used functional MRI to map human posterior parietal cortex (PPC) functions. It found specialized sensorimotor areas for visually guided reaching and object exploration, with some regions showing multiple task activations.
Area of Science:
- Neuroscience
- Cognitive Neuroscience
- Functional Neuroimaging
Background:
- The human posterior parietal cortex (PPC) is crucial for sensorimotor integration.
- Understanding the functional specialization within the human PPC is essential for comprehending visually guided actions and object manipulation.
Purpose of the Study:
- To investigate the functional organization of the human posterior parietal cortex (PPC).
- To identify specific brain regions involved in sensorimotor processing for visually locating objects, reaching, grasping, and manual exploration.
Main Methods:
- Functional magnetic resonance imaging (fMRI) was employed to measure cortical activation.
- Participants performed three tasks: saccadic eye movements, visually guided reaching to grasp, and manual shape discrimination.
Main Results:
- Distinct PPC regions were activated during saccadic eye movements, visually guided reaching, and manual shape discrimination.
- Several PPC areas demonstrated significant activation across multiple sensorimotor tasks, indicating multifunctional properties.
- Hemispheric asymmetries were observed in activation patterns during visually guided reaching to grasp.
Conclusions:
- The human PPC exhibits a functional organization that includes multifunctional regions and task-specific areas.
- The identified patterns suggest a functional homology between human and nonhuman primate PPC organization.
- Asymmetric processing of certain manual abilities in the human PPC was noted.
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