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A new study on Northwestern University has raised serious concerns for all those backing the recent push to decriminalize marijuana. Study researchers found unhealthy alterations in the mind structures of heavy marijuana users,? changes that resemble those based in the brains of people with schizophrenia.
The study looked at daily marijuana use that began between 16 to 17 and lasted for around 3 years. At the time of the research, participants was not using marijuana for about two years.
“The study links the chronic use of marijuana to those concerning brain abnormalities that appear to last for a minimum of a few years after people stop utilizing it,” said study author Matthew Smith, an assistant research professor in psychiatry and behavioral sciences at Northwestern University. “With the movement to decriminalize marijuana, we want more research to know its impact on the mind.”
The study cohort included 97 subjects: healthy controls, subjects having a marijuana use disorder, individuals with schizophrenia but no history of a marijuana use disorder and schizophrenic patients having a marijuana use disorder.
Ninety percent of the 15 marijuana smokers who had schizophrenia in the study began using marijuana heavily before they showed indications of the mental disorder. They also discovered that marijuana-related brain abnormalities are associated with an undesirable working memory performance, based on their report within the journal Schizophrenia Bulletin.
“The abuse of popular street drugs, for example marijuana, may have dangerous implications for young adults who’re developing and have developed mental disorders,” said study author Dr. John Csernansky, chair of psychiatry and behavioral sciences at Northwestern University. “This paper is among the first to reveal the utilization of marijuana may bring about the alterations in brain structure that have been associated with having schizophrenia.”
Researchers conducted a structural MRI on participants to correlate abnormalities in these regions with working memory, the opportunity to remember and instantly process information. While previous research has found effects of marijuana on the cortex, few research has checked out chronic marijuana use in otherwise healthy people and individuals with schizophrenia, the researchers noted.
The team found that memory-related structures in the brains of chronic users seemed to shrivel and collapse inward, perhaps as a result of reduction in neurons. While all the chronic users in the study showed evidence of brain alterations, subjects with schizophrenia had more significant deterioration within the thalamus, a vital structure for learning, memory and communications between brain regions.
The study team added that chronic marijuana use could raise the underlying process driving schizophrenia.
“If someone has a genealogy of schizophrenia, they’re increasing their risk of developing schizophrenia if they abuse marijuana,” Smith said.
“A tremendous quantity of addiction research has focused on brain regions traditionally associated with reward/aversion function, and therefore motivation,” noted study author Dr. Hans Breiter, a professor of psychiatry and behavioral sciences at Northwestern. “This study very nicely extends the set of regions of concern to include those involved with working memory and higher level cognitive functions essential for how good you organize your life and can operate in society.”
“For those who have schizophrenia and you frequently smoke marijuana, you might be in danger for poor working memory, which predicts your everyday functioning,” Smith said.
