The human brain controls all the functions of thought, memory, sensory input and vital bodily functions. A common misconception is that humans use only ten percent of their total brain capacity, but in fact a majority of brain processing power is used in the hindbrain rather than the cerebrum responsible for conscious thought and decision-making. The functions of the hindbrain cover the primitive instincts and vital bodily functions such as heartbeat, breathing and digestion. Also called the rhombencephelon, the hindbrain consists of the pons, the cerebellum and the medulla oblongata.
Most functions of the hindbrain revolve around vital bodily processes, and are governed by the medulla oblongata. This part of the brain is located at the base of the skull just above the spinal column and below the cerebellum. It governs the expansion and contraction of the diaphragm and lungs, the function of the heart and the dilation/contraction of blood vessels by working with the hypothalamus to ensure homeostasis is maintained. The hindbrain also controls involuntary digestive and respiratory reflexes such as vomiting, coughing, swallowing and sneezing to expel dust and other foreign particles from the body.
Just above the medulla oblongata is the pons, which acts as a link to the cerebellum. Sexual arousal, sensory analysis and motor control occur in the pons; auditory input in particular first makes contact with the pons. The sensation of equilibrium or lack thereof is governed by two fluid sacs, one in each inner ear. One of the most important functions of the pons is the sleep paralysis reflex; it prevents movement during sleep and stops potentially dangerous sleepwalking. The left and right hemispheres of the brain also connect through the pons in addition to their connection through the corpus callosum.
The other functions of the hindbrain are controlled by the cerebellum, its largest portion. Chiefly, the cerebellum is responsible for muscle tone, coordination and fine motor control, such as finger movement. The occipital lobe and the rest of the cerebrum work with the cerebellum to provide humans with hand-eye coordination skills. Emotions and the associated physical stimuli such as increased heart rate are under the control of the cerebellum, as is long-term and short-term memory.
Functions of the hindbrain are possible because of the wrinkled surface of the cerebellum. The more wrinkles or folds there are on the cerebellum, the more developed the associated neural network is. Although new neurons rarely are created after adolescence, new neural connections constantly form.
