With marijuana becoming legal in some states it can be easy to believe that the drug is harmless. But in the scientific community there have been many studies that have linked marijuana use with increased instances of psychosis.
Little is known about how marijuana affects the developing brain with teen users. A report by University of Maryland researchers finds a possible link between teen marijuana use and problems with cognitive functioning measured in adulthood. The study was conducted using animal models, but the findings could indicate that similar problems are likely in humans.
The study was published in a recent issue of the journal Neuropsychopharmacology. The study shows mice given marijuana during adolescent development had changes in the cortical oscillations, which refers to the activity in the neurons located in the brain, and abnormalities can signal the presence of schizophrenia.
The mice were administered small amounts equal to a low dose of tetrahydrocannabinol, which is the active ingredient in marijuana. This practice was repeated for 20 days while the mice were adolescents. Following the marijuana doses, the mice were placed with their families to continue their development into adulthood.
The mice were evaluated for changes in the cortical oscillations. The researchers discovered significant differences in the oscillations, in addition to observing impairment in the animals’ cognitive functions.
Repercussions of Even Small Amounts of Marijuana
The researchers were surprised to see that despite the low doses of marijuana administered to the mice, the changes to the brain function were observable in adulthood.
The administering of marijuana in low doses was repeated with adult mice that had never been given the drug before. Unlike the results observed with the teen mice, the adult mice did not exhibit any changes in cortical oscillations and no changes were detected in their cognitive behavior.
Effects in Adolescents
Senior author of the paper, Dr. Asaf Keller, explains that the findings may indicate that adolescence is a time when marijuana use can make a significantly negative impact on brain development. During adolescence, Keller says, the frontal lobes of the brain are still developing. In contrast, the back of the brain develops earlier. As a result, the frontal cortex is more severely affected by drug use during adolescence.
This area of brain development can impact important functions. For instance, the frontal cortex is responsible for impulse control and planning, and it is the region of the brain in which abnormalities are linked with a diagnosis of schizophrenia.
Genetics Playing a Role
The authors of the study note that a genetic susceptibility also likely plays a significant role in the changes observed in the brain that can lead to schizophrenia. However, if a person has that susceptibility and then adds marijuana use in low doses, they could trigger the development of the disorder.
The study highlights one major area that has not been fully explored in the legalization of marijuana. The findings indicate that for those who have a genetic predisposition to develop schizophrenia, even moderate use of marijuana during adolescence could have life-changing implications.
The research team hopes to continue its efforts to understand the impact that marijuana use by teenagers can have on adult brains. Ultimately, the work could lead to the development of strategies to reverse the damage to the brain functions and help individuals with cognitive problems regain full range of ability.
Parents should talk with their children about these findings, adding the information to their conversation related to drug and other substance use. When teens understand their parents’ wishes and rules related to drug use, they are more likely to make decisions that align with their parents’ expectations.