Daily use of marijuana can disrupt brain function, study finds
In a study, researchers revealed chronic use of the drug caused a decrease in the number of receptors involved in a wide array of important mental and bodily functions, including concentration, movement coordination, pleasure, pain tolerance, memory and appetite.
Marijuana, also known as cannabis, is abused more than any other illegal drug in America, according to the US National Institute on Drug Abuse. When smoked or ingested, the drugâs psychoactive chemical binds to numerous cannabinoid receptors in the brain and throughout the body, which influence a range of mental states and actions. One of two known types of cannabinoid receptors, called CB1, is involved primarily in the central nervous system.
In conducting the study, researchers compared the brains of 30 chronic daily marijuana smokers to non-smokers over the course of roughly four weeks.
Using molecular imaging, researchers were able to visualise changes in the participantsâ brains and found the cannabinoid CB1 receptors of the smokers had decreased by 20% compared to the otherwise healthy people with limited lifetime exposure to marijuana.
âWe were able to show for the first time that people who abuse cannabis have abnormalities of the cannabinoid receptors in the brain,â lead author Dr Jussi Hirvonen said in a Society of Nuclear Medicine news release.
The researchers re-scanned 14 of the smokers after one month of abstinence and found a notable increase in receptor activity in areas that were deficient at the beginning of the study.
âThese findings, the investigators concluded, suggest the adverse effects of chronic marijuana use are reversible.
âThis information may prove critical for the development of novel treatments for cannabis abuse. Furthermore, this research shows that the decreased receptors in people who abuse cannabis return to normal when they stop smoking the drug,â Dr Hirvonen added.