“The human brain allows a person to reason, function intellectually, express personality and mood, and interact with the environment” (Sugerman, 2008, p. 277). Our brains are truly extraordinary. Considering how much we still don't know about the brain demonstrates how complex and amazing the brain is. No other organ is like the brain, and all other organs would not be able to function without the brain. “The three main divisions of the brain are (1) the forebrain, consisting of the two cerebral hemispheres; (2) the midbrain which includes the quadrigeminal bodies and cerebral peduncles; and (3) the hindbrain, which includes the cerebellum, pons, and medulla” (Sugerman, 2008, p. 277). First, the brainstem consists of the midbrain, medulla oblongata, and pons, which connect the hemispheres of the cerebrum, cerebellum, and spinal cord (Sugerman, 2008, p. 277). The brainstem is made up of nerve bodies called the reticular formation, which are responsible for some of the body's most vital operations, cardiovascular and respiratory functions (Sugerman, 2008, p. 277). These two functions are performed involuntarily every day. We don't need to think about breathing every few seconds or making our heart beat constantly. This process also keeps us awake. Different nuclei are consequently responsible for different motor functions (Sugerman, 2008, p. 278). “The cerebellum is composed of gray and white matter, and its cortical surface is convoluted like the surface of the brain. It is also divided by a central fissure into two lobes connected by vermis” (Sugerman, 2008, 284). The cerebellum has many functions, it is responsible for reflexes, involuntary fine-tuning of motor control, and maintaining balance and posture through extensive neural connections with the medulla (Sugerman, 2008, 284). The small cerebrum or cerebellum “receives information from the balance system of the inner ear, sensory nerves, and the auditory and visual systems. It is involved in the coordination of motor movements, as well as in fundamental aspects of memory and learning, in homeostatic control." The diencephalon is composed of four main parts: epithalamus, thalamus, hypothalamus and subthalamus. The thalamus is responsible for "transmitting cerebral cortex information received from different regions of the brain... Axons from every sensory system (except olfaction) synapse here as the last site of transmission before the information reaches the cerebral cortex ” (Sci.uidaho, n.d., paragraph 2,3). The thalamus surrounds the third ventricle and allows us to perceive numerous sensations (Sugerman, 2008, 283).