Neurons are not the only brain cells that think

Most people, if they think about the matter at all, probably think of thinking as something done by the huge network of specialised, electrically conductive cells called neurons that occupies the upper half of their skulls. And, as far as it goes, that is true. The 86bn neurons in a human brain do indeed do much of the cognitive heavy lifting. But not all of it.Supporting them is a cast of three other varieties of cell—microglia, oligodendrocytes and astrocytes—collectively called glial cells (short for “neuroglia”, from the Greek for “nerve glue”). Until recently, these were neglected by neurology. That has changed. Glial cells (their filaments stained green in the section of rat hippocampus pictured, with neuron filaments stained blue and the nuclei of both stained red) are . The results have blown away the idea that they are mere glue.