Making up the central nervous system are the brain, spinal cord and the peripheral nervous system. The highly complex brain is the center of the nervous system, in charge of the body. According to the National Institute of Neurological Disorders and Stroke, the brain gives us all the qualities that define our humanity and refers to the brain as the "crown jewel" of the body.
Cerebrum
The cerebrum makes up the largest part of the brain and consists of a right and left hemisphere, or half circle. According to the Brain Explorer, an educational resource provided by the Lundbeck Institute, the frontal, parietal, occipital, and temporal lobes make up each hemisphere. The cerebral cortex, also known as "gray matter," is the outermost part of the cerebrum and covers the whole surface of the brain. Gray matter makes up the neuron enriched cerebral cortex. Neurons send electrical signals within the brain. Under the cerebral cortex lies the white matter, which is full of axons that send impulses to other parts of the brain. Responsibilities of the white matter also include regulating body temperature, blood pressure and heart rate. The main functions of the cerebral cortex, notes authors Linda Urden, Kathleen Stacy and Mary Lough in their book "Critical Care Nursing: Diagnosis and Management," include sensory perceptions--seeing and hearing and so forth--muscle control and intellectual functions such as memory, emotions and speech.
Cerebellum
The cerebellum, or hindbrain, located at the bottom of the brain, consists of two hemispheres filled with outer gray matter and inner white matter. Impulses within the cerebellum are communicated to pathways in the brain to assist with the coordination, precision and timing of movement, though the cerebellum is not responsible for actually starting a person's movement. According to the article titled "Cognition, Emotion and the Cerebellum," it is thought that the cerebellum plays a role not only in motor control, but also in emotional control and cognitive processing.
Brainstem
The brainstem is made up of the midbrain, the pons and the medulla oblongata. The midbrain and the pons send stimuli to and from the brain through sensory tracts and motor pathways. These tracts and pathways regulate things like smell, vision, eye movement, hearing, salivation, tears and taste. According to the book "Critical Care Nursing: Diagnosis and Management," the medulla oblongata, near the spinal cord, controls several involuntary functions such as swallowing, hiccupping, coughing, vomiting, heart rate, respirations and arterial vasoconstriction within arteries. The rhythm of a person's respirations are controlled through the pons and medulla oblongata working together.
References
- National Institute of Neurological Disorders and Stroke: Brain Basics: Know Your Brain
- Brain Explorer: Brain Atlas
- Center for Neuro Skills: Cerebellum
- "Critical Care Nursing: Diagnosis and Management"; Linda Urden, Kathleen Stacy and Mary Lough; 2009
- Oxford Journals: Brain: A Journal of Neurology: Cognition, emotions and the cerebellum
