The brain stem is an area of the brain located at the base of the skull and connecting the cerebral hemispheres to the spinal cord. It is comprised of three distinct parts: the midbrain, the pons, and the medulla oblongata. The brain stem is responsible for the regulation of a variety of physiological functions, including body temperature, heart rate, respiration, digestion, sleep, and reflex activity. It is also involved in higher functions such as consciousness and motivated behaviour, as it is partially responsible for producing and regulating dopamine and other neurotransmitters. In addition, the brain stem plays an important role in relaying sensory and motor signals between the brain and peripheral nervous system. Overall, the brain stem is a complex and highly integrated component of the central nervous system.

See also: nitric oxide, endocannabinoid system, default mode network