The Study with Thermography using the infrared images by Yin Lo, Ph.D.
The left picture is the before acupuncture, the red color region means the pain or inflamed, the picture 9 doesn’t show the red region, pain or inflammation significantly decreased after acupuncture treatment.
Recently, acupuncture has been shown to increase the nitric oxide levels in treated regions, resulting in increased local blood circulation. Effects on local inflammation and ischemia have also been reported.
Acupuncture appears to have effects on cortical activity, as demonstrated by magnetic resonance imaging and positron emission tomography.
Theoretical Background for Specific Duration Times.
1. 15-20 minutes : The Nan Jing-The Classic of Difficulties, Chapter 23
According to ?The Nan Jing , Qi and Blood move through the meridians at the rate of six *Cun for each complete inhalation and exhalation.? The total length of the Meridians and Collaterals equals 1620 cun.?1620 divided by 6 equals 270, so it is said that 270 breaths are required for Qi to make one complete cycle through the body.? However, this number could vary based on a person’s breath rate.? If a person breathes 14 times/minute, it will take 20 minutes (270/14) for Qi to make a complete cycle.? If a person breathes 18 times/minute, only 15 minutes (270/18) will be needed for Qi to make the complete cycle.? Therefore needle retention time can be calculated around 15-20 minutes.
*Cun is a Chinese proportional unit of length
2. 30min: The Ling Shu-Spiritual Pivot, Chapters 15 & 18
the Qi and Blood circulated through the channels 50 times per day. Since 24 hours equals 1440 minutes, dividing 1440 by 50, we get the 28 minutes and 48 seconds. This is where we get the guideline for approximately 30 minutes of needle retention time.
Pain transmission can also be modulated at many other levels in the brain along the pain pathways, including the periaqueductal gray, thalamus, and the feedback pathways from the cerebral cortex back to the thalamus. Pain blockade at these brain locations is often mediated by neurohormones, especially those that bind to the opioid receptors (pain-blockade site).
Some studies suggest that the analgesic (pain-killing) action of acupuncture is associated with the release of natural endorphins in the brain. This effect can be inferred by blocking the action of endorphins (or morphine) using a drug called naloxone. When naloxone is administered to the patient, the analgesic effects of morphine can be reversed, causing the patient to feel pain again. When naloxone is administered to an acupunctured patient, the analgesic effect of acupuncture can also be reversed, causing the patient to report an increased level of pain. It should be noted, however, that studies using similar procedures, including the administration of naloxone, have suggested a role of endogenous opioids in the placebo response, demonstrating that this response is not unique to acupuncture.
One study performed on monkeys by recording the neural activity directly in the thalamus of the brain indicated that acupuncture’s analgesic effect lasted more than an hour. Furthermore, there is a large overlap between the nervous system and acupuncture trigger points (points of maximum tenderness) in myofascial pain syndrome.
Evidence suggests that the sites of action of analgesia associated with acupuncture include the thalamus using fMRI (functional magnetic resonance imaging) and PET (positron emission tomography) brain imaging techniques, and via the feedback pathway from the cerebral cortex using electrophysiological recording of the nerve impulses of neurons directly in the cortex, which shows inhibitory action when acupuncture stimulus is applied. Similar effects have been observed in association with the placebo response. One study using fMRI found that placebo analgesia was associated with decreased activity in the thalamus, insula and anterior cingulate cortex.