Two Sources of Cannabis Addiction
Brain changes from using THC too frequently cause withdrawal and craving.
Cannabis causes two distinct changes in brain chemistry, physiology, and function that combine to create dependence. Its main psychoactive ingredient, THC, reduces the normal number of natural cannabinoid receptors, a process called downregulation. THC also alters reward circuitry, bending motivation toward continued cannabis use.
Downregulation of Cannabinoid Receptors: THC stimulates cannabinoid receptors (CB1) in the brain more strongly and longer than our natural cannabinoid chemistry. With CB1receptors activated far above normal physiological levels, most people enjoy physical relaxation, emotional calming, novel vivification of sensations, increased appetite (munchies) and ease falling asleep, among other changes to the texture of experience. As a result of THC’s strong activation, the brain reduces the availability of CB1 receptors in an effort to regain chemical balance.
When cannabis use is repeated before CB1 receptors upregulate back to normal levels, their reduction in numbers accumulates and lingers after THC’s high has ended. Normal levels of the natural cannabinoids anandamide and 2-AG do not have the normal number of CB1 receptors to activate This creates a relative cannabinoid deficiency state.
THC-induced cannabinoid deficiency state is the opposite of being high. Physical relaxation becomes restlessness. Emotional calm becomes anxiety and irritability. Munchies become decreased appetite. The novelty of sensations becomes boredom. Ease of sleeping becomes insomnia. These are withdrawal symptoms—the five signs of using cannabis too frequently.
Hijacked Reward Circuitry: Craving arises because THC alters brain reward circuity…After too frequent THC use has altered reward circuity by chronically flooding it with dopamine to the point of changing cellular structure, this portion of the brain starts crying out for repeat use when cannabis is stopped.
For complete article go to Research – Psychology Today