And you thought it was all about the neurons.In an experiment that might seem like something only a mad scientist would conjure, researchers injected human brain cells into the brains of mice to see how it would affect the way the mice thought. It did: the mice got smarter. But the cognition boosting cells weren’t neurons, they were the red-headed step-children of neuroscience called astrocytes. The study turns on its head the role historically attributed to astrocytes of simply supporting the all important function of neurons without playing a significant role in how we learn and think. It may very well be that humans owe much of their unique cognitive capabilities to astrocytes.
When the German pathologist Rudolf Virchow first visualized them through a microscope in 1846 he called them ‘glia,’ the Greek word for glue, because the cells seemed to only fill in the space between the brain’s neurons. Subsequent study over the next century and a half only served to confirm the idea that these glial cells were only important insofar as they supported the function of neurons. The glial cells in the brain – called astrocytes for their numerous processes which project outward in star-like radiance – make sure the fluid surrounding neurons has the right concentration of ions and other molecules, and is clear of molecular waste. But research has emerged over the past few decades that suggest astrocytes might play more than a housekeeping role in the brain and may actually be important for cognitive function.