Motor Learning and the Cerebellum

Some new research just came out in Neuron that is incredibly relevant to the work I do in my lab.  The myriad (billions) of granule cells in the cerebellum send their axons, the parallel fibers, to the purkinje cells (pictured below).  This junction is of utmost importance…excitation of purkinje cells leads to the inhibition of behavior, whereas as inhibition of the purkinje cells generally leads to motor movement.  While common sense and many experiments have shown that movement-inducing inhibition of the purkinje cells (called “Long-Term Depression,” or LTD) is vital for motor learning, new research like this points towards the role of excitation of the purkinje cells (called “Long-Term Potentiation,” or LTP), and thus inhibition of motor behavior, as well.  I study motor learning in the Medina lab at Upenn, with a focus on the parallel fiber-purkinje cell synapse.  This research certainly adds more to the puzzle of motor learning…the mystery grows…

Check out the “video abstract” at http://www.cell.com/neuron/

image/Ramon y Cajal