THE STUDY: In 1999, a scientific study using MRI was performed to determine how acupuncture stimulation influenced the brain (CNS). The study revealed that when two points were stimulated (ST 36, and LI4), ACTIVATION of the hypothalamus (part of brain involved in controlling the release of many hormones from the pituitary gland) and the nucleus accumbens (part of brain associated with motivation, reward and dopamine activity): and DEACTIVATION of rostral part of anterior cingulated cortex (associated with “executive function”, or goal representaion and maintenance, evaluative process, strategic process and performance) amygdala formation (regulates emotions and triggers response to danger), and hippocampal complex (part of the brain that assists in storing memory by sorting and sending new bits of information to other parts of the brain).
COMMENTS:
So what does this mean in layman terms? Stimulation of certain acupuncture points activates hormones and/or areas of the brain which are known to reduce sensitivity to pain and stress as well as promoting relaxation AND deactivating those areas of the “analytical” brain, responsible for excess thinking, memory or anxiety.

COMMENT ON STRESS AND PAIN:
When the body is constantly in a state of stress (whether it be from pain, emotional, or even a work situation) this is known as the “flight or fight” response. The “flight or fight response” activates our Sympathetic Nervous System. The sympathetic nervous system focuses our bodies so that we may try to escape the impending danger or stress. Our breathing and heart rate increase, and many of our body parts contract in order to increase blood oxygenation specifically to our heart and muscles so that we may be better capable of running away. Constriction shunts blood and secretions away from the skin and digestive tract, our pupils expand urine is retained (You can’t fight a bear when you are urinating or having a bowel movement, and its not a necessity to digest that big meal you had for lunch) When the body is relaxed, the Parasympathetic Nervous System kicks in. The heart rate slows down, and smooth digestive function ensues, much needed nutrient rich blood and secretions are able to flow through the body and its many organs, the pupils relax and the breath slows down.
I am a Licensed acupunturist in Portland Oregon and I operate out of my own clinic For a wealth of educational information on Chinese Medicine, please my TCM page. Alysia Anderson, L.Ac