Researchers found a hidden circuit in the cerebellum that helps explain how people learn from experience. The result was published in Nature and came from a collaboration between scientists at Duke and Harvard Medical School.
Climbing fibers are nerve pathways that send strong error signals when a movement does not go as planned. These signals activate Purkinje cells and cause bursts of calcium inside them. Calcium signals help the brain change connections and learn. At the same time, climbing fibers also activate inhibitory cells that can stop those calcium signals.
The new work shows climbing fibers mainly activate a group called ML12. ML12 cells suppress another group, ML11, and ML11 normally reduces learning. When many climbing fibers fire together, inhibition falls and Purkinje cells make larger calcium signals to reshape connections.
Difficult words
- cerebellum — part of the brain that helps control movement
- climbing fiber — nerve pathway that sends strong error signalsClimbing fibers
- Purkinje cell — a type of brain cell in the cerebellumPurkinje cells
- calcium — mineral that helps signals and changes in cells
- inhibitory cell — brain cell that reduces activity of other cellsinhibitory cells
- suppress — to make something weaker or stop it
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Discussion questions
- Have you ever learned from a mistake? Give a short example.
- What do you think a "hidden circuit" in the brain means?
- Why might collaboration between different scientists help research?
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