Definition of Terms

1. Human Nervous System- the part of a body that coordinates its voluntary and involuntary actions and transmits signals between different parts of its body. Mostly, it consists of two main parts, the central nervous system (CNS) and the peripheral nervous system (PNS). 2. Central Nervous System- the processing center for the nervous system. It receives information from and sends information to the peripheral nervous system. The two main organs of the CNS are the brain and spinal cord. The brain processes and interprets sensory information sent from the spinal cord. 3. Cerebrum- in humans, the cerebrum is the largest part and superior-most region of the vertebrate central nervous system. It is also divided into approximately symmetric left and right cerebral hemispheres. 4. Cerebellum- a region of the brain that plays an important role in motor control. The cerebellum does not initiate movement, but it contributes to coordination, precision, and accurate timing. 5. Brain Stem- the posterior part of the brain, adjoining and structurally continuous with the spinal cord. The brain stem provides the main motor and sensory innervation to the face and neck via the cranial nerves. 6. Medulla- a portion of the hindbrain that controls autonomic functions such as breathing, digestion, heart and blood vessel function, swallowing and sneezing. 7. Pons- includes tracts that conduct signals from the cerebrum down to the cerebellum and medulla, and tracts that carry the sensory signals up into the thalamus. 8. Midbrain- a portion of the central nervous system associated with vision, hearing, motor control, sleep/wake, arousal (alertness), and temperature regulation. 9. Spinal cord- a long, thin, tubular bundle of nervous tissue and support cells that extends from the brain. It functions primarily in the transmission of neural signals between the brain and the rest of the body. 10. Peripheral Nervous System- consists mainly of nerves, which are