Actually, the medulla oblongata probably has nothing to with ornery вЂ¦ surprise! As if movies ever tell the truth вЂ¦ Anyway, the medulla oblongata has a crucial role in body homeostasis. The Medulla Oblongata: 'Alligators are ornery cause of their Medulla Oblongata'! (Water boy, 1998). In addition the pons (which means bridge) connects the cerebellum to the rest of the brain. It may also play a role in generating dreams. The Pons: The pons region of the brain stem contains nuclei that contribute to the control of sleep, respiration, swallowing, bladder control, hearing, equilibrium, taste, eye movement, facial expressions, and posture. It is thought that in humans the red nucleus influences arm swing during gait, crawling in babies and motor control of some of the larger shoulder and arm muscles, but not the legs. In many vertEbrates, it is a relay center for motor pathways that effect limb flexion. Neurons in the red nucleus contain inordinate amounts of iron which when oxidized conveys a red hue. Degeneration of these neurons is the cause of ParkinsonвЂ™s disease, a condition in which the patient is unable to suppress unwanted muscle contractions resulting in constant tremors of the extremities. Neurons from the substantia nigra ascend to the cerebrum and synapse with structures of the basal nuclei, a part of the brain involved in skeletal muscle control. The neurons from this region produce dopamine as their neurotransmitter and neuromelanin is derived from the same precursor that produces melanin, L-dopa. This is due to the pigment neuromelanin (similar to melanin) which is produced in these cells.

The substantia nigra (dark substance) gets its name from its dark appearance in fresh tissue. For example, вЂњJaws,вЂќ or вЂњWatcher in The WoodsвЂќ kind of stuff. The inferior colliculi help coordinate head and eye movements in respond to sudden sounds that cause you to abruptly move your head and turn your eyes toward the sound. This reflex involves input from the eyes via the optic nerves, integration of the signal in the superior colliculi, and efferent signals to the muscles that control eye movements via cranial nerves III, IV and VI. The paired superior colliculi (colluculus singular) coordinate the movement of our eyes as we track a moving object. The copora quadrigemina are subdivided into two regions, the two superior colliculi and the two inferior colliculi. Spend time looking at the image search on the midbrain.

Three unique clusters of cell bodies (nuclei) are observed in the midbrain the corpora quadrigemina, the substantia nigra, and the red nucleus. Running through the midbrain is a hollow tube which connects the third and fourth ventricles (The ventricles of the brain are hollow spaces filled cerebral spinal fluid). The midbrain: The midbrain is the upper most portion of the brain stem and is situated between the diencephalon and the pons. Downloaded from Image Quest Britannica BYU-Idaho. We can survive without a cerebrum, although we would not be conscious that we were alive, but the body cannot survive without the brain stem. It should also be noted the brain stem is essential for maintain critical body functions, such as respiration and regulation of the heart, and that we cannot survive without its functions. The brain stem is also the site where groups of axons (nerve tracts) either exit the brain as cranial nerves or continue on into the spinal cord.Indeed, ten of the twelve pairs of cranial nerves (III - XII) exit the central nervous system from the brain stem. The brain stem is subdivided into three regions: the midbrain, the pons, and the medulla oblongata. The region of the brain that connects the brain to the spinal cord is the brain stem.

Brain stem parts