A stylized illustration of an individual astrocyte.

they are blood-barrier regulators. they are nervous tissue food-providers. they are the glia most responsible for monitoring and improving the brain tissue after the brain experiences damage.

this glial cell has vastly diverse skill sets and as a result are a highly relevant source of study-material of today’s neuroscience researchers. contested in numbers in the brain, some scientists believe they may be the most numerous glia, but overall it is generally accepted they make up between 20% and 40% of the human brain’s glial cells. There are three known varieties of astrocyte, detailed in the chart below.