Researchers found that heavy cannabis use reduces brain activity during working memory tasks, leading to cognitive struggles. Brain scans showed changes in regions responsible for memory and decision-making. While abstaining may help, more research is needed to understand long-term effects. Credit: SciTechDaily.com
A massive new study sheds light on how cannabis affects the
brain, particularly during cognitive tasks.
Researchers analyzed over 1,000 young adults and found that both heavy
lifetime use and recent cannabis consumption significantly reduced brain
activity during working memory tasks. This impairment was linked to worse
performance on tasks requiring focus, problem-solving, and
instruction-following. Brain imaging revealed that key regions responsible for
decision-making and attention were affected.
Cannabis Use and Brain Function:
A Groundbreaking Study
A new study published in JAMA Network Open examines
how both recent and long-term cannabis use affects brain function during
cognitive tasks.
As the largest study of its kind,
researchers analyzed over 1,000 young adults aged 22 to 36 using brain imaging
technology. They found that 63% of heavy lifetime cannabis users showed reduced
brain activity during a working memory task, with a similar impact seen in 68%
of recent users.
Reduced Brain Activity and
Working Memory Impairment
This decrease in brain activity was
linked to poorer performance on working memory — a crucial function that helps
people retain and use information for tasks. For instance, working memory
enables someone to follow instructions, mentally visualize concepts, or solve
problems like math equations.
“As cannabis use continues to grow
globally, studying its effects on human health has become increasingly
important. By doing so, we can provide a well-rounded understanding of both the
benefits and risks of cannabis use, empowering people to make informed decisions
and fully comprehend the potential consequences,” said the study’s first author
Joshua Gowin, PhD, assistant professor of radiology at the University of
Colorado School of Medicine on the University of Colorado Anschutz Medical
Campus.
In the study, heavy users are
considered young adults who’ve used cannabis more than 1000 times over their
lifetime. Whereas, using 10 to 999 times was considered a moderate user, and
less than 10 times was considered a nonuser.
MRI Scans Reveal Cannabis’ Impact
on Brain Function
The researchers studied the neural
response of participants during a magnetic resonance imaging (MRI) session and
gave them seven cognitive tasks to complete. The tasks tested working memory,
reward, emotion, language, motor skills – such as tapping a finger to map brain
control, relational assessment and theory of mind.
The researchers found that cannabis
had a statistically significant effect on brain function during working memory
tasks, meaning the observed impact is very unlikely to be due to random chance.
This effect was seen in both recent and lifetime cannabis users. The impact was
less significant for the other tasks.
“We applied the highest standards to
our research, setting rigorous thresholds for statistical significance across
all seven cognitive function tests. To minimize the risk of false positives, we
employed false discovery rate (FDR) correction. While some of the other tasks
indicated potential cognitive impairment, only the working memory task showed a
statistically significant impact,” adds Gowin.
Key Brain Regions Affected by
Heavy Cannabis Use
During working memory tasks, the
researchers found heavy cannabis use appeared to reduce brain activity in
certain areas of the brain (dorsolateral prefrontal cortex, dorsomedial prefrontal
cortex, and anterior insula). These regions of the brain are involved in
important cognitive functions such as decision-making, memory, attention, and
emotional processing.
However, Gowin mentions their research
also suggests that abstaining from using cannabis before doing a cognitive task
could help to improve performance. “People need to be aware of their
relationship with cannabis since abstaining cold turkey could disrupt their
cognition as well. For example, heavy users may need to be more cautious,”
Gowin says.
No comments:
Post a Comment