Testing Your Reflexes

When you scratch your leg, how many neurons go to work? To find out, scientists tickled turtles to generate a reflexive scratch reaction in their back legs. The above image shows a superimposed time-lapse of the scratch in action.

Researchers found that this simple reflex involved a widely distributed network of spinal cord neurons. This network included neurons in the upper spinal cord, in addition to those in the back leg and lower spinal cord.  Scientists believe that large, widespread neural networks provide more opportunities for formation of new connections following injury. By studying these networks, scientists hope to better understand the recovery process.