What weed really does to your brain, according to hundreds of thousands of scans
Marijana has been known to take a toll on the body.
It can irritate the lungs, damage blood vessels and accelerate heart rate. Not to mention the scromiting, the screaming — and vomiting! — that can accompany long-term, heavy use.
The brain also takes some hits.
“From a brain imaging perspective, marijuana use is consistently associated with measurable changes in brain function,” Dr. Daniel Amen, founder of Amen Clinics, which has conducted hundreds of thousands of scans to measure blood flow and activity in patient brains, told The Post.
A study last year out of the University of Colorado, for example, linked chronic use to a decline in working memory, the brain’s ability to retain, process and use information immediately.
The other ways marijuana can drain your brain may blow your mind. Here’s a look at six of the potential puff-ects.
Coordination
The CDC estimates that 52.5 million Americans, or about 19% of the US population 12 and older, get high at least once a year. The legalization of cannabis in many states has increased access to grass, putting the ole noggin in the crosshairs.
“Marijuana users demonstrate widespread reductions in cerebral blood flow, particularly in regions critical for memory, coordination, emotion and executive function,” Amen said.
The main psychoactive compound of marijuana, THC, is the culprit here. It disrupts the brain’s cerebellum and basal ganglia, which are responsible for motor control, balance and coordination.
That could manifest as lane weaving while driving, body swaying due to instability and delayed reactions. These effects are most pronounced in the first hour after marijuana use and can last several hours.
Memory
THC also binds to receptors in the hippocampus, which plays a critical role in memory formation. It’s one of the brain regions most affected by weed, Amen noted.
“Cannabis users show significant hippocampal hypoperfusion, with studies demonstrating reductions of up to 13–17% compared to controls,” Amen said, referring to the sustained blood flow reduction to the hippocampus.
“This is clinically meaningful because the hippocampus is highly vulnerable to neurodegenerative processes and is essential for learning and memory consolidation,” he added.
In short, marijuana can disrupt the process of turning short-term memories into long-lasting ones.
Judgment
“The prefrontal cortex, responsible for judgment, impulse control and decision-making, shows reduced activation as well,” Amen said.
This can fuel smokers to seek out immediate rewards while overlooking long-term consequences, undermining their ability to assess risk and adapt to new information.
Attention
Marijuana brings the smoke — and the brain fog.
Hash can make it harder to plan, organize, concentrate and multitask. Blame THC’s effect on the prefrontal cortex.
Sensory perception
Cannabis can intensify taste, sound, smell, vision and touch, making music feel more immersive and colors more vibrant, because THC activates brain regions linked to sensory processing.
On the flip side, marijuana can also dull night vision and slow glare recovery, making nighttime driving trickier.
Mental health
“The amygdala, which regulates emotional processing, demonstrates decreased activity in imaging studies,” Amen said.
“This may contribute to emotional blunting in some individuals, but cannabis use is also associated with increased rates of anxiety, paranoia and psychosis, particularly in high-frequency users or those with genetic vulnerability,” he noted.
Research shows that users are also at increased risk of mood changes, panic attacks, depression, addiction, schizophrenia and suicidal ideation.
Some of these brain changes may ease upon quitting marijuana. Research into the long-term effects of frequent use and neural recovery is ongoing.
“Findings suggest that marijuana use is associated with global reductions in brain function, rather than enhancement,” Amen said.
“While some individuals report short-term benefits, imaging data indicate potential negative effects on memory, coordination, emotional regulation and executive function — especially with chronic or heavy use.”
Science still hasn't figured out what I have been observing for 50 years:
Marijuana use stops the maturing process in most users
Because of this, marijuana is responsible for the dramatic drop in the birth rates in western societies - youth tend to remain in their teens emotionally right through their twenties and thirties as long as they continue using.
Emotionally immature youth don't want to raise children.
