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Updated: May 12, 2026
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Behavioral Assessment of Manual Dexterity in Non-Human Primates
Published on: November 11, 2011
Numerical representation for action in the parietal cortex of the monkey
Hiromasa Sawamura1, Keisetsu Shima, Jun Tanji
1Department of Physiology, Tohoku University School of Medicine, Sendai 980, Japan.
Nature
|February 23, 2002
Summary
Primates
Area of Science:
- Neuroscience
- Cognitive Neuroscience
- Primate Behavior
Background:
- The anterior parietal association area integrates somatosensory signals for body and object representation.
- This area guides movements using sensory information.
Purpose of the Study:
- To investigate if the anterior parietal cortex is active during numerically based behavioral tasks.
- To determine the role of the superior parietal lobule in processing numerical information related to self-action.
Main Methods:
- Monkeys performed cyclical tasks involving repeated movements (A, B, A).
- Cellular activity was recorded in the superior parietal lobule, inferior parietal lobule, and primary somatosensory cortex.
- Neural activity was analyzed for selectivity to movement number and type.
Main Results:
- Superior parietal lobule neurons showed activity reflecting the number of self-movement executions.
- This number-selective activity was largely specific to the type of movement performed.
- Similar numerical representation of self-action was less frequent in the inferior parietal lobule and rare in the primary somatosensory cortex.
Conclusions:
- The superior parietal lobule plays a crucial role in processing numerical information related to self-initiated actions.
- This processing is essential for upcoming motor selection and planning.
- The findings highlight a specific role for the superior parietal lobule in numerical cognition and sensorimotor control.
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01:14Action Potential
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01:23Somatosensory, Motor, and Association Cortex
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