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marijuana side affects memory loss

The debate continues over the possible long-term effects of marijuana use, with a recent study suggesting marijuana use during the teen years may lead to memory loss and changes to the brain’s structure. In addition to lower scores on memory tests, the subjects in this study also had differences in the shape of the hippocampus – the area of the brain responsible for forming long-term memories.

Researchers Follow Teens to Young Adulthood

Researchers from Northwestern University looked at 97 young adults in this study. Some had a history of marijuana use between the ages of 16 and 17 that persisted nearly three years. Other subjects had no history of marijuana use. Some of the test subjects had also been diagnosed with schizophrenia; a portion of those subjects also had a history of marijuana use. The second group was included because previous research indicates that schizophrenia is a factor in both short and long-term memory problems. People diagnosed with this mental disorder are also more likely to smoke marijuana.

Subjects diagnosed with schizophrenia that also reported to smoking marijuana daily scored the worst on the memory tests out of all the test subjects. Their scores were 26 percent worse than the other subjects diagnosed with schizophrenia that did not smoke marijuana. In the group of subjects without a mental disorder, those who smoked marijuana performed 18 percent worse on the memory tests than those that did not.

Memory Loss, Misshapen Brains

The researchers also found that the subjects that used marijuana as teens had misshapen brains, particularly around the area of the hippocampus. These findings supported previous animal studies that showed changes to the hippocampus in rat brains after exposure of THC, the active ingredient in marijuana, during the adolescent years. A New Zealand study also found that teens that began persistent marijuana use during the adolescent years also had an IQ loss of around eight points by the middle of their adult years.

These findings, which were published in the March edition of the journal Hippocampus, seem to follow a similar trend for marijuana users that begin smoking during their teen years. However, researchers caution that the study has limits in its ability to determine whether marijuana was the direct cause of the memory loss or the changes to brain structure.

At Pasadena Recovery Center, we help patients every day that are struggling with addictions to substances like marijuana. From the withdrawal process to treatment and recovery, we offer the support necessary for abusers and addicts to turn from the substances and discover a productive life of sobriety. If you are struggling with substance abuse or addiction, help is available. Contact Pasadena Recovery Center today at 866-663-3030.

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