4 ways cannabis affects your brain

Updated on June 23, 2020

There are a number of different drugs that can wreak havoc on your brain, and cannabis is no exception. Though it is a relatively mild drug in terms of the impacts that it has on how we act and behave, marijuana is actually just as impactful on the brain as some other drugs. Indeed, cannabis use can absolutely impact on your brain and how it works; understanding the impacts on the brain of cannabis use is therefore essential if you are to be safe while using it yourself!

So, how does cannabis and marijuana use actually impact on the brain? Let’s have a look.

How Cannabis Use Impacts on the Brain

Increase in Psychosis

When you take cannabis and marijuana, research has found a direct relationship between doing so and an increase in psychosis. Specifically, psychosis is a medical condition which is characterised by the sufferer feeling “detached” from the real world. Some such examples of psychosis and being detached from the real world include seeing hallucinations and schizophrenia. Some people also hear things when they are experiencing psychosis, as triggered by marijuana use. Continued cannabis use over an extended period of time has been found to trigger periods of psychosis on a longer term basis than simply while the drug is active in our systems. This is especially true for young cannabis users, where using marijuana early on in life (especially over an extended period) can have long term psychological impacts and can increase the rate of psychosis in these individuals.

IQ Drop

When you take marijuana, you may well start the process of your IQ falling. Research has found that the consumption of marijuana by teenagers and young people can impact on their IQ and intelligence in later life. Though it was determined that the impact was not massive, it was still significant in those individuals who used marijuana four times a week or more; therefore, there is absolutely a link between marijuana use and a slight fall in IQ. 

This is especially the case in teenagers; older cannabis and marijuana users may experience a lesser impact on their IQ.

Pleasure Control

Did you know that our brains are responsible for how we feel and experience pleasure and pain—and the use of marijuana can actually impact on this sensation? Indeed, a study was carried out that was interested in determining how our brains respond to images of our favorite foods, and how the use of marijuana over an extended period of time impacted on this. The results of the studies were enlightening, too; they found that, for people who had regularly taken marijuana for 12 years or longer, the brain responded more positively (indicating greater pleasure and happiness) when shown images of weed smoking equipment than with the individual’s favorite food. This was in comparison with people who didn’t smoke weed or didn’t smoke it as regularly; for these people, the brain responded more strongly to the image of their favorite food.

As such, it can also be said that the extended use of marijuana has an impact on how we experience pleasure—in fact, marijuana could actually prevent the brain from showing as much excitement to our favorite things than it would normally, indicating that people who use marijuana often may get less happiness from everyday life. That’s pretty depressing, actually—but some solace can be taken in the fact that this is mainly impacted for people who consume vast amounts of cannabis, and those who indulge in marijuana less regularly don’t experience these symptoms as badly.


We all love a tasty snack, but you might be surprised to learn the marijuana use could actually be responsible for making us all want to eat more! Indeed, a study that was carried out on mice concluded that mice who had been dosed with marijuana were actually far hungrier than their counterparts and tended to spend more time eating!

Further research into the topic indicated that the munchies phenomenon caused by marijuana is actually a result of the drug increasing the production of hunger chemicals. It was initially believed that the cause would be the drug turning off the production of neurons which normally suppress our appetite, but this wasn’t actually true as they had expected.

This would also suggest that people who consume marijuana will be more hungry and want to eat more munchies than those who don’t. Though we can’t be sure the pathways and effects are exactly the same in mice and people, of course, there is also plenty of evidence suggesting that this is the case for people. So, marijuana may not be the best drug for those looking to lose weight—although if you’ve been thinking of tackling an eating challenge, maybe it could give you a bit of a boost in your appetite?

In Summary

Marijuana is a relatively mild drug in terms of its effects, all things considered, despite being classed as a Schedule I drug. However, extended use of marijuana can have a number of effects on the health and general functioning of our brains! From making us feel more hungry to making life less happy overall, there are many ways that marijuana use can impact our brains aside from just the four ways that we have listed above. With that being said, medical marijuana can actually offer a number of positives, too—so it’s really a matter of weighing up the pros and the cons.