The substantia nigra is responsible for unconscious motor actions. Emotions, storing new information and thirst and hunger are functions that happen in the forebrain. 

The motor cortex is located in the back of the frontal lobe. It is the area of the frontal lobe responsible for voluntary movement.

Sympathetic neurons are fictitious and not found in the nervous system. Afferent neurons are synonymous to sensory neurons. They are responsible for sending information in the form of a stimulus signal to the interneurons. The interneurons translate the stimulus so that information may be passed to the efferent or motor neurons. In other words, sensory neurons receive and transmit information to interneurons that then relay these messages to the motor neurons.

The sympathetic nervous system is responsible for arousal and energy expenditure. When faced with an alarming or challenging situation, this nervous system will act and cause the following physiological responses: accelerated heart beat, increase in blood pressure, a slow down in digestion, and initiation of perspiration. These characteristics compose the "fight or flight" response.

The nervous system is first subdivided into two large branches: the peripheral and central nervous systems. The central nervous system is composed of the brain and the spine and the peripheral is slightly more complicated. It can be subdivided into the autonomic (controlling internal organs and glands) and the somatic (skeletal). The enteric nervous system does not play a part in this overall nervous system. Instead, it is responsible for gastrointestinal processes. 

The sympathetic nervous system is responsible for initiating the fight or flight response. Conversely, the parasympathetic nervous system is responsible for ending the response. The parasympathetic nervous system will oppose the effects via conserving energy, lowering blood pressure and heart rate, and lowering your blood sugar. 

The somatic nervous system makes it possible for an organism to sense and move in its environment. This system is primarily comprised sensory receptors—found in eyes, ears, nose, tongue, and skin—and motor nerves that relay information from the central nervous system. The nerves in the somatic nervous system are usually under conscious control. Unconscious control such as cardiac muscle movement is regulated by the autonomic nervous system. Nerves that transmit messages from the central nervous system to glands, cardiac muscle, and smooth muscle are part of the autonomic nervous system. 

Wernicke's area is the language area that is responsible for comprehending spoken word as well as formulating written and spoken language. A person with damage to this area could develop speech that is incomprehensible. This particular speech disorder is known as Wernicke's aphasia. 

The sympathetic nervous system mobilizes the body during emergencies. These responses include the dilation of pupils, inhibition of salivary glands, relaxation of bronchi, acceleration of heartbeat, inhibition of digestive activity, the release of glucose from the liver, relaxation of the bladder, and inhibition of sexual arousal.

After an emergency the parasympathetic nervous system depresses the heightened bodily responses to normal levels. These responses include the constriction of pupils, stimulation of salivary glands, constriction of bronchi, slowing of heartbeat, stimulated digestive activity, stimulated gall bladder activity, contraction of the bladder, and the stimulation of sexual arousal.