Marijuana, or so the familiar War on Drugs meme went, screwed with your brain. In fact, smoke weed and your future was an unremitting default of crap jobs, poverty and killed dreams. While it is very clear that certain groups of people should not use cannabinoids, others are helped by them. Clearly, simplistic approaches and explanations do not fit the bill here.

There are also some other things we know at this point. For example, teenagers should not use cannabis. There are clear connections between the negative impact of cannabinoids and the developing brain. Pregnant or nursing mothers should also not use cannabinoids for that reason.

That said, this is the very simple subtext.

Here is the reality. Cannabis - actually cannabinoids in the plant - works on the brain and body in certain ways. It clearly affects memory. Yes, it can cause people to “forget” things. However, this ability can also be used to treat certain conditions as medicine. Further, because marijuana tends to have holistic impact, overall outcomes should be the point of study. Not single points in time. This, by definition, makes testing such impact more difficult. Regardless, this is a question that will continue to be raised until more definitive answers are in place.

Furthermore, there are also places where even young children need access to certain cannabinoids[1]. Those with Dravet’s Syndrome are perhaps the perfect example. Childhood epilepsy sufferers appear to be able to use cannabinoids to normalize brain function.

The bottom line? Pot does affect your brain and memory. Whether that is a negative or positive impact depends very much on individual circumstance. One thing is for sure. More research is desperately needed.

how cannabis affects your brain


The question is not whether cannabis affects your brain. It does. The question is how, when, and for how long?

The scientific answer is that cannabinoids essentially act as a biological switch. They impact how the brain’s electrical signals work. Different cannabinoids, in fact, different plants, can create different effects[2]. This includes memory and the brain’s workings. For example, it is well known that indica strains tend to cause sleepiness and slow down brain function overall. However, sativas are known to be mentally stimulating.

Then of course, there is this fact. Not all memory is the same kind of memory. This, in turn, can have dramatic impact on downstream effect. For example, when pot is ingested, the body turns off neurotransmitter signals that tell the brain that the body is in pain or depressed. Outcome? The person no longer is in pain or depressed.

Ultimately, the impact of cannabis on the brain can be positive or negative.


The first thing to realize is that there are different kinds of memory. The human brain is in many ways just like a computer. Long term memory is what is on your hard drive. Short-term memory is what exists temporarily until properly saved where it can be retrieved. There is a bit more to it than that of course. But this is how cannabis can impact memory in the human brain.


Ok, so this is the stereotype about pot. Information about the present, including interacting with immediate environments, tend to be affected. This is short term processing in other words. Attention also falls into this bucket. If you are in a situation where you are required to respond to an external environment quickly, this can be a negative. However, if you suffer from PTSD, it is exactly this feature of cannabis that can help patients learn how to cope.


This is also related to concentration. It is also very clear, particularly for recreational users, that ganja use can have a negative impact. Some pot users seem distracted. They also sometimes cannot properly pronounce words or come up with strange ones. Studies seem to indicate that memory of words themselves might be negatively affected in the moment. That said, one study that followed 3,300 individuals for 25 years found this: users “lost” about one word for every five years of marijuana they had smoked. This is hardly the kind of thing that is going to turn off recreational users in their twenties.

memory, cannabis and creativity


This is also related to short-term memory. This means, literally, the ability to process information in real time. It is used when you are learning something. Further, it helps you build connections. It is your ability to hold a train of thought and further process it.

Bottom line, cannabis can affect working memory. Studies to date have shown that participants tend to do worse on tests when they have just consumed THC then when they have not. Being stoned does impede some kinds of performance required for interaction with the rest of the world. That said, there are also others, including creatives to athletes, who say that it is precisely this feature of cannabis that lets them find both creative and physical “flow.” The brain “forgets” in other words, or does not process as accurately, feelings of pain.


Spatial memory is the ability to remember details in the immediate environment. In other words, this is the ability that allows one to easily recall the last location of the keys. Or being able to find your way out of a maze. This kind of memory is also affected by cannabis. A 2014 study[3] on found that THC can drastically and negatively affect this kind of memory. In the 1990’s, this was also tested in mice[4]. Those who had recently ingested THC had a harder time finding their way out of mazes.


Here the jury and research so far, is out. Long term memory is like the brain’s storage unit of what you have perceived during your life. Cannabis may impact your ability to remember the past or it may not. What is clear is that the drug may be able to help control unwanted thoughts about the past. This is one of the biggest issues facing PTSD sufferers for example. Marijuana is able to allow them to soften the blow.


Cannabis is very good at helping people “forget” traumatic memories. These are memories of incidents where individuals have been put in overwhelming and negative situations. This can include war or combat. However, it can also include more “everyday” occurrences. This includes any traumatic event that was overwhelming for the individual it affected. As a result of such experiences, the brain frequently “remembers” the trauma. This could be in the form of a flashback. It could also be in the form of another upsetting concept triggered by an external source. This can include smells, light and sound. All sensory perceptions in other words.

What marijuana appears to be able to do for individuals with this condition is pretty amazing. It is not that individuals “forget” what happened to them. Rather, it appears that the “blunting” of external stimuli actually help reduce memory triggering. The PTSD symptoms themselves are also less overwhelming.

cannabis and memory


If you are noticing negative effects from your cannabis use, you need to evaluate them. If using weed for a recreational purpose, there are a few easy answers. Change strains. Stop altogether. Slow down. You also might consider that you might have an undiagnosed medical condition. Even if you are using more marijuana “only” to manage stress, it is important to identify the reasons you depend on pot to a point where it worries you. Or causes worrying side effects.

If using the drug for a medical reason, there are other things to consider. Every drug has potential side effects. Are the ones you are suffering from cannabis worse than other medications or going without? Further, in this case, particularly if in a situation where medical use is legal, experiment. Look for other strains.

It is medical users with either chronic pain or PTSD (or both) who are actually providing one of the most fascinating windows into a world that remains mostly defined by unanswered questions.

One thing is very clear, however. The negative impacts of the drug can absolutely be addressed and mitigated if used as medication. And it is those features of cannabis which should also no longer be used to discredit either it, or further delay legalization, testing and understanding.

External Resources:
  1. The Cannabinoid Receptor Agonist WIN 55,212-2 Facilitates the Extinction of Contextual Fear Memory and Spatial Memory in Rats - PubMed
  2. The effect of cannabis use on memory function: an update
  3. Acute Administration of THC Impairs Spatial but Not Associative Memory Function in Zebrafish - PubMed
  4. Acute Administration of THC Impairs Spatial but Not Associative Memory Function in Zebrafish - PubMed
This content is for educational purposes only. The information provided is derived from research gathered from external sources.

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