Motor neurons don’t just move muscles. They may direct that motion too

Though textbooks assign them a passive role, motor neurons can help coordinate movements

A fruit fly

Certain motor neurons organize fruit fly sucking through a domino-like activation sequence, with each neuron activating its target muscle while sending signals back to the brain to release the “brake” on the next step.

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Motor neurons, the nerve cells that control muscles, have a reputation as passive messengers.