Functions And Roles Of Human Sympathetic Nervous System Anatomy Model

The human sympathetic nervous system anatomy model displays the autonomic nervous system, including the sympathetic and parasympathetic nerves located in the trunk. The sympathetic nerves are yellow, and the parasympathetic nerves are white. A total of 53 sites are shown. The autonomic nervous system (vegetative nervous system) controls visceral activity, participates in glandular secretion, smooth muscle contraction, and heartbeat, respiration, and reproductive functions. The autonomic nervous system consists of two parts: the sympathetic and parasympathetic nervous systems.

The main functions of the sympathetic nervous system are to dilate the pupils, increase heart rate, constrict blood vessels in the skin and internal organs, dilate coronary arteries, increase blood pressure, dilate bronchi, decrease gastrointestinal motility, relax bladder wall muscles, reduce saliva secretion, increase sweat secretion, and contract the arrector pili muscles.

In short, sympathetic nervous system activity plays a major role when the body is in a state of tension or activity. The parasympathetic nervous system, on the other hand, has the opposite function; it helps maintain physiological balance in a resting state, and its functions are threefold.

First, it enhances gastrointestinal activity and digestive gland secretion, promotes urination and defecation, conserves the body's energy, constricts the pupils to reduce stimulation, promotes glycogen production for energy storage, slows the heart rate, lowers blood pressure, and constricts the bronchi to conserve energy.

Under normal circumstances, the sympathetic and parasympathetic nervous systems, with their opposing functions, are in a state of balance and regulation. In these two systems, when one plays a positive role, the other plays a negative role, thus effectively balancing, coordinating, and controlling the body's physiological activities. However, if the sympathetic and parasympathetic nervous systems are dysfunctional, a series of behavioral disorders will occur. For example, some children may exhibit unusual excitement throughout the day, possibly due to an overactive primitive tactile system, resulting in excessive activation of the sympathetic nervous system.

The human sympathetic nervous system anatomy model is a highly valuable teaching tool in medical education. Its correct use not only helps in understanding complex neural pathways but also deepens the understanding of the clinical relevance of autonomic nervous system function.