Glia Tell Neurons to Build Synapses

After decades of neglect by researchers more interested in know-it-all neurons, brain cells classified as “glia” are getting some respect. Although glia account for 90% of the cells in the adult human brain, they've been written off as simple scaffolding that supports neurons, as sources of nutrition, or as a waste-disposal mechanism for sopping up extra ions and neurotransmitter molecules. But a new study on page 657 shows that glia play a more important role in neuron-to-neuron communication: They tell neurons to start talking to one another.