Auteur : [[Leslie Kaminoff]] MOC : [[YOGA]] - [[ANATOMIE]] Source : [[3 GARDEN/Notes/Yoga Anatomy]] Date : 202302021322 *** ## Le système somatique, autonome et entérique SNS ANS ENS Le système *conscient* : **The somatic nervous system** (SNS) creates responses in our musculoskeletal system, specifically in the striated muscles that we use to move, breathe, and act in the world. The SNS is what we use to do actions such as stepping one leg back or opening our mouth or flinging our arms out when we lose our balance. **The autonomic nervous system** (ANS) creates responses in the smooth muscle of our visceral organs, the cardiac muscle of our heart, our blood vessels,7 adipose tissue, and glands. The ANS increases or decreases activity in our glands and organs in patterns that are called **sympathetic responses and parasympathetic responses**, and most of our glands and organs receive messages from both sympathetic and parasympathetic motor neurons (figure 4.4). **Sympathetic responses** increase our alertness and readiness to respond to events in the outside world by increasing our heart rate and blood flow to our skeletal muscles and brain or by slowing activity in our digestive system. Sympathetic responses are often characterized as a whole-body, fight-or-flight response, but this is only an extreme expression of sympathetic activity. In nonthreatening day-to-day activities, sympathetic responses can be modulated, discrete, and localized. **Parasympathetic responses** increase internal activities related to digestion, homeostasis, growth, and healing by increasing peristalsis, glandular activity, and blood flow to our digestive system or by slowing the heart rate. Often characterized as being about resting and digesting, our parasympathetic responses are not simply the absence of activity but are also active motor responses oriented to the internal environment rather than the outer world.8 ([Location 1306](https://readwise.io/to_kindle?action=open&asin=B0998616FH&location=1306)) **The enteric nervous system** (ENS) is sometimes called our second brain because it has a network of enteric ganglia where sensory neurons, glial cells, and motor neurons communicate and where sensory input leads to processing and motor responses without traveling through the CNS. The ENS creates responses specifically in the smooth muscles, glands, and endocrine cells of the digestive tract and allows parts of our digestive system to work without interaction with the brain and spinal cord. ([Location 1329](https://readwise.io/to_kindle?action=open&asin=B0998616FH&location=1329))