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Published on: August 8, 2019
When pliers become fingers in the monkey motor system
M A Umiltà1, L Escola, I Intskirveli
1Dipartimento di Neuroscienze, Università di Parma, Via Volturno 39, 43100 Parma, Italy.
Summary
Tool use in monkeys shows that motor neurons adapt to new tools, embodying them as extensions of the hand. This goal-centered brain organization underlies our capacity for tool use.
Area of Science:
- Neuroscience
- Primate behavior
- Evolutionary biology
Background:
- Tool use is a key evolutionary development.
- Understanding the neural basis of tool embodiment is crucial.
Purpose of the Study:
- To investigate how the primate brain represents and controls tool use.
- To determine if motor cortical activity adapts to novel tool properties.
Main Methods:
- Monkeys were trained to use both normal and reverse pliers.
- Cortical motor neuron activity was recorded during grasping tasks with hands and tools.
Main Results:
- Motor neurons active during hand grasping also activated when using pliers.
- This neural adaptation occurred even with reverse pliers requiring opposite finger movements.
- The findings suggest a goal-centered representation in motor cortex.
Conclusions:
- Tool use is facilitated by the brain's ability to embody tools.
- Primate cortical motor areas are functionally organized around goals, not just movements.
- This goal-centered organization is fundamental to the evolution of tool use.
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