“Head Lights” — The Discovery Files

With the help of light-emitting diodes as small as neurons, University of Michigan researchers are unlocking the secrets of neural pathways in the brain. The researchers have built and tested in mice neural probes that hold what are believed to be the smallest implantable LEDs ever made. The new probes can control and record the activity of many individual neurons, measuring how changes in the activity of a single neuron can affect its neighbors.