Marijuana Use and Adolescence
A recent study done at the University Of Maryland School Of Medicine suggests that regular use of marijuana in adolescence may cause permanent impairment of brain functioning and cognition and may lead to serious psychiatric disorders. As reported in Science Daily last week, this study, which was published is Neuropsychopharmology (which is a publication of Nature magazine) hopefully will provide insight on the potential long term effects of marijuana use.
Previous studies done concerning marijuana use and adolescence had shown that use of the drug by those under the age of 16 are at greater risk of permanent cognitive functioning. It is also suggested in teens that develop psychiatric disorders such as schizophrenia may have genetic dispositions favorable for development of the disorder and marijuana use triggers those dispositions. Adolescence is a critical time in development of the human body and especially the brain.
In the study researchers studied cortical oscillations in mice…
These oscillations are patterns of neuron activity which underlie brain functioning. Young mice were given very small doses of the active ingredient in marijuana for 20 days and only for that time period. It was discovered that the young mice had impaired cognitive functioning going into adulthood. In comparison, adult mice where administered the drug and hadn’t been exposed to it previously. It was found that the adult mice showed no impairment in their ability to perform cognitive tasks.
In looking at the underlying mechanisms of brain development, the frontal cortex is the area of the brain which develops during the adolescent years. This brain area, which contains the hippocampus, is responsible for planning and impulse control. Damage to this developing area of the brain due to marijuana use. Also, this area of the brain is the area most affected by schizophrenia, according to the researchers in this study.
Although this study did not focus on the human population, the finding do have precedent in another study conducted by Sion Kim Harris from the Boston’s Children’s Hospital and Harvard Medical School. In the study, Harris points out that the marijuana plant contains hundreds of chemicals labelled cannabinoids. Human brains are sensitive to the active chemicals in marijuana because we have many receptors in the brain that are considered “cannabinoid” receptors. These receptors are the most common in the brain and are also located in our blood vessels, heart cells, nervous system and glands.
Our brains produce chemicals called endocannabinoids that bind to cannabinoid receptors. One of those chemicals is called anandamide as is part of the endocannabinoid system in our brain. This system helps keep neuron activity in balance in our brain and regulates levels of those neurotransmitters that are important such as those that regulate pleasure, mood, pain and appetite among others. This system also shapes brain growth by directing neurons to grow in the right places in the brain and promotes healthy development of the myelin sheath. This sheath is a fatty white substance that aids in the transmittal of information throughout the brain
THC, the main ingredient in marijuana, is stronger than anandamide and will override the endocannabinoid system. It causes the system to be suppressed and the brain will try to correct itself by providing chemicals to excite the system. Adolescent brains are still developing and are very malleable and plastic. Use of marijuana during adolescence can cause significant cognitive impairments in those areas of the brain that regulate judgment, reward, and memory. Among those structures noted by Harris as being most affected is the hippocampus, as was noted in the University of Maryland study.
The hippocampus is the main area where memory is formed, stored, and retrieved. It is also important for sleep regulation and the calming down of our stress response. Harris notes that THC reduces neuron activation which can suppress memory formation and continued use will erode those neuron connections involved with memory formation. Harris also notes that even if the adolescent user stops using, neurophysiological decline will continue through adulthood.
In addition to these studies, additional studies have been conducted by agencies like the National Institute of Health gauging the attitudes towards drug use among adolescence. In a National Institute of Health study published last year, it found that attitudes concerning the harmfulness of marijuana became more relaxed as teenagers transitioned from junior high to the high school years. Along with that decrease in seeing that the use of marijuana was harmful, use of marijuana itself increased.
Tim Powers – bald, tattooed, a business professional by day and rocker by night. Sober by the grace of God since the 8th of May in the year of our Lord 2003. Sharing my stories and my self in order to pay it forward. You can follow me on Twitter @tpowersbass42.