Sensory neurons in human muscles provide important information used for the perception and control of movement. Learning to move in a novel context also relies on the brain’s independent control of these sensors, not just of muscles, according to a new study published in the journal Current Biology.
Each muscle can have tens or hundreds of encapsulated sensory receptors, and these “sensors” are called muscle spindles. Spindles differ from other sensory receptors as they also receive nerve fibers from the central nervous system itself, which acts to control spindle output.
There are more nerve fibers travelling to and from spindles than to the actual muscle tissues generating force and powering movement. Despite more than a hundred years of research on this class of sensory receptors, however, it has been unclear how, why and when the nervous system chooses to independently control spindles.
Recording of signals from single nerve fibers during motor learning shows that signal patterns from sensory receptors in human muscle change substantially as a function of learning state
Image Credit: Michael Dimitriou