Neuroanatomy and glial cells come in many types (see, for example, the nervous system section of the list of distinct cell types in the adult human body). Neurons are the information-processing cells of the nervous system: they sense our environment, communicate with each other via electrical signals and chemicals called neurotransmitters across synapses, and produce our memories, thoughts and movements. Glial cells maintain homeostasis, produce myelin, and provide support and protection for the brain's neurons. Some glial cells (astrocytes) can even propagate intercellular calcium waves over long distances in response to stimulation, and release gliotransmitters in response to changes in calcium
Radial glial cell visualized using the electron microscope or high-resolution time-lapse microscopy, through which neurons can be seen tightly wrapped around radial glia as they travel upwards through the cortex. Additional evidence suggests that many neurons may move between neighboring radial glial fibers during migration. While excitatory neuronal migration is largely radial, inhibitory, GABAergic neurons have been shown to undergo tangential migration. Tangentially migrating neurons also appear to initiate contact with radial glial fibers in the developing cortex of ferrets, implicating radial glial cells in both of these forms of migration. As radial glia seem to differentiate late in spinal cord development, near