Human brain as nuclei involved in the regulation of many essential processes including breathing, control of eye movements and balance. The reticular formation, a network of nuclei of ill-defined formation, is present within and along the length of the brainstem. Many nerve tracts, which transmit information to and from the cerebral cortex to the rest of the body, pass through the brainstem. The human brain is primarily composed of neurons, glial cells, neural stem cells, and blood vessels. Types of neuron include interneurons, pyramidal cells including Betz cells, motor neurons (upper and lower motor neurons), and cerebellar Purkinje cells. Betz cells are
Satellite glial cell these cells. Current research is revealing that SGCs are also able to respond to some of the same chemical stimuli as neurons. The research is ongoing and SGCs role in injury repair mechanisms is not yet fully understood. Glial cells, including SGCs, have long been recognized for their roles in response to neuronal damage and injury. SCGs have specifically been implicated in a new role involving the creation and persistence of chronic pain, which may involve hyperalgesia and other forms of spontaneous pain. SGCs have the ability to release cytokines and other bioactive molecules that transmit pain neuronally. Neurotrophins and