Lessons for circuit function from large insects: towards understanding the neural basis of motor flexibility

Motor behaviors result from information processing that occurs in multiple neural networks acting at all levels from the initial selection of the behavior to its final generation. A long-standing research interest is how single neural networks can help generate different motor behaviors, that is, the origin of motor flexibility. Modern experimental techniques allow studying neural network activity during the production of multiple motor behaviors. Recent data provide strong evidence that the neural networks controlling insect legs are individually modified in task-dependent and finely tuned fashions. Understanding the mechanistic basis of these neural network modifications will be of particular interest in the upcoming years.

► New tools enable researchers to analyze complex motor behaviors and motor flexibility.
► Only when speed changes, but not in steady locomotion, does neural control coordinate stance velocity of legs.
► Motor flexibility arises from task-specific and finely tuned modifications in sensorimotor processing.
► Unraveling the nature of the descending signals from the brain needs prime attention in the next years.