Somatic nervous system
The somatic nervous system (also referred to as the SNS or voluntary nervous system) is the name given to the subset of neurons - both afferent and efferent - that control skeletal muscle contraction in response to sensory stimuli, enabling voluntary movement. It is part of the larger peripheral nervous system, and includes all sensory and motor neurones that interact with spinal cord.
The external stimulus from the environment sends the signal to the sensory neuron (afferent neuron). After that, the neuron send the information up to the central nervous system (CNS), which as an intermediate neuron. CNS intergrates and interprets all the information. The output signal is released and transmitted to the motor neuron (efferent neuron). Therefore, the somatic neurons are causing the voluntary movement of muscle, for instance, skeletal muscle. In contrast, the smooth muscle is having involuntary movement of muscle contraction. For examples, digestive system, respiratory tract, blood vessel and reproductive tract (uterus).
- ↑ Kapalka GM. Chapter 3 - Pharmacodynamics. In: Nutritional and Herbal Therapies for Children and Adolescents. 1st Edition. Cambridge, MA:Academic Press. 2010:47-70
- ↑ Dee Unglaub.S.Human physiology : An integrated approach, 6th edition. p402