Oowah oowah, is my disco call
In the mid-1800s researchers discovered cells in the brain that are not like neurons (the presumed active players of the brain) and called them glia, the Greek word for “glue.” Even though the brain contains about a trillion glia—10 times as many as there are neurons—the assumption was that those cells were nothing more than a passive support system. Today we know the name could not be more wrong.
Glia, in fact, are busy multitaskers, guiding the brain’s development and sustaining it throughout our lives. Glia also listen carefully to their neighbors, and they speak in a chemical language of their own. Scientists do not yet understand that language, but experiments suggest that it is part of the neurological conversation that takes place as we learn and form new memories. (…)
All neurons have certain characteristic attributes: axons, synapses, and the ability to produce electric signals. As scientists peered at bits of brain under their microscopes, though, they encountered other cells that did not fit the profile. When impaled with electrodes, these cells did not produce a crackle of electric pulses. If electricity was the language of thought, then these cells were mute. German pathologist Rudolf Virchow coined the name glia in 1856, and for well over a century the cells were treated as passive inhabitants of the brain.
At least a few scientists realized that this might be a hasty assumption. (…) Today the mystery of glia is partially solved. Biologists know they come in several forms. One kind, called radial glia, serve as a scaffolding in the embryonic brain. Neurons climb along these polelike cells to reach their final location. Another kind of glia, called microglia, are the brain’s immune system. They clamber through the neurological forest in search of debris from dead or injured cells. A third class of glia, known as Schwann cells and oligodendrocytes, form insulating sleeves around neurons to keep their electric signals from diffusing.
