Does Cannabis Use Affect Cognitive Capacity?

cannabis cognitive capacity

Does cannabis use affect cognitive capacity? This question has been around for almost as long as the plant itself. Many a skeptic will quickly say things like “weed makes you dumb!” Defenders will insist that the plant can do no harm and that “being dumb makes you dumb!”

While cannabis use can certainly lead to a state of wonder, increase the complexity of your thought patterns, and encourage an ascent to enlightenment, its neural effects, and how those go on to affect cognition, still remain unclear.

With a background and focus on data science, the WoahStork team prefers to let the data speak for itself rather than allow any preconceived notions to influence the interpretation of results. In this article, we put forth a review of the limited evidence as to whether cannabis use affects cognitive capacity and speculate as to the biases of these studies and the interpretations of their findings.

cannabis use affect cognitive capacity
American astronomer, astrophysicist, and science popularizer Carl Sagan would certainly argue that cannabis is capable of providing a user with insights — a phenomenon that can go on to enrich one’s cognitive skillset.

A recent article published in JAMA Psychiatry sought to review the influx of academic research articles pertaining to the effects of cannabis use on cognition. In an unfortunate realization for heavy cannabis users, the evidence seems to suggest that daily cannabis use can have a detrimental effect on cognitive capacity.

For example, heavy cannabis use can cause acute impairment of learning and memory, attention, and working memory (Crane, 2013; Crean, 2011; Ranganathan 2006). Furthermore, when compared to nonusers, nonintoxicated regular cannabis users also seem to perform worse on measures of global neuropsychological function, which includes the domains of executive function, attention, motor skills, and verbal abilities (Grant, 2003). Perhaps too much of a good thing is always a bad thing? “Everything in moderation” is a potent proverb for a reason.

However, what about those who need to medicate on a daily basis? Reducing one’s consumption of cannabis could counteract its medicinal effects. Thus, we sought to investigate the cases in which the cognitive deficits apparently caused by daily cannabis use were minimized.

A majority of the cited studies make the disclaimer that the age at which one begins using cannabis heavily is perhaps the most significant factor. That is, many of these results may have been skewed by the inclusion of subjects who began using cannabis heavily before the age of 18. In fact, the earlier age of onset of cannabis use is usually associated with greater neuropsychological impairment (Gruber, 2012). Adult-onset users actually seem to avoid these neurocognitive effects (Meier, 2012).

Since the body’s endocannabinoid system is so crucial to neurodevelopmental processes (Lubman, 2015), the introduction of exogenous cannabinoids could disrupt brain development. This hypothesis has been confirmed by the observation that pubertal rats that are treated with a cannabinoid agonist (i.e. a drug that encourages an increase in endocannabinoids) showed persistent deficits on object recognition tasks compared to control pubertal rats.

endocannabinoid system
Your body’s endocannabinoid system is wildly complex. It’s role neural development is incredibly important — responsible for forming neural synapses, encouraging neural growth, and more! Simply put — your body’s system that responds to cannabis is complex and consuming cannabis before this system has fully matured can be problematic.

While these behavioral measures seem quite robust, a neural correlate of these use-induced deficits has yet to truly surface. It has recently been shown that heavy cannabis use can shrink key brain regions.

However, the remainder of neuroimaging studies of adolescent and adult cannabis users yield relatively inconsistent findings. Researchers are beginning to discover that cannabis use’s classic comorbidity with alcohol use may actual be the detrimental component. For example, a study that carefully matched participants on alcohol intake showed no evidence of morphological brain alteration – abolishing their previous findings before they controlled for alcohol consumption (Weiland, 2015).

cannabis use affect cognitive capacity
The hippocampus — one of the brain regions thought to be affected by regular cannabis use.

Fortunately, any and all behavioral and neural impairments seem to be entirely reversible given a month of abstinence (Schreiner, 2012) and studies have shown that the use of CBD can help to alleviate some of these seemingly worrisome impacts on cognitive capacity—almost negating them (Yucel, 2016).

Let us also not forget that the studies including in this particular review paper may have been cherry picked due to the fact that the work was financed in part by support from Forum Pharmaceutical, and Pfizer – companies clearly nervous about the impact of legal marijuana on their corporations. Thus, when asking the question “does cannabis use affect cognitive capacity?”, don’t forget to read the disclaimer on anyone providing you with the answers — their responses may be biased.

The moral of the story: If considering cannabis use for recreational purposes only, it may be best to wait until after neurodevelopmental processes have reached maturation (~18 years old), not partake daily, and take regular tolerance breaks. Furthermore, alcohol use may be the true culprit at play and consumption of alcohol should be curtailed regardless of cannabis use.

If considering cannabis for medical purposes, be sure to include a high dosage of CBD to counteract any possible negative effects to render it safer for children and daily use. The WoahStork staff recommends sprinkling some ACDC, Charlotte’s Web, or Harlequin into your next joint. These strains are high in CBD and could help curtail some of the negative side effects we discussed in this “does cannabis use affect cognitive capacity” article.


Crane, Natania A., et al. “Effects of cannabis on neurocognitive functioning: recent advances, neurodevelopmental influences, and sex differences.”Neuropsychology Review 23.2 (2013): 117-137.

Crean, Rebecca D., Natania A. Crane, and Barbara J. Mason. “An evidence based review of acute and long-term effects of cannabis use on executive cognitive functions.” Journal of addiction medicine 5.1 (2011): 1.

Grant, Igor, et al. “Non-acute (residual) neurocognitive effects of cannabis use: a meta-analytic study.” Journal of the International Neuropsychological Society 9.05 (2003): 679-689.

Gruber, Staci A., et al. “Age of onset of marijuana use and executive function.” Psychology of Addictive Behaviors 26.3 (2012): 496.

Lubman, Dan I., Ali Cheetham, and Murat Yücel. “Cannabis and adolescent brain development.” Pharmacology & therapeutics 148 (2015): 1-16.

Meier, Madeline H., et al. “Persistent cannabis users show neuropsychological decline from childhood to midlife.” Proceedings of the National Academy of Sciences 109.40 (2012): E2657-E2664.

Ranganathan, Mohini, and Deepak Cyril D’souza. “The acute effects of cannabinoids on memory in humans: a review.” Psychopharmacology 188.4 (2006): 425-444.

Schreiner, Amy M., and Michael E. Dunn. “Residual effects of cannabis use on neurocognitive performance after prolonged abstinence: A meta-analysis.”Experimental and clinical psychopharmacology 20.5 (2012): 420.

Weiland, Barbara J., et al. “Daily marijuana use is not associated with brain morphometric measures in adolescents or adults.” The Journal of Neuroscience 35.4 (2015): 1505-1512.

Yücel, M., et al. “Hippocampal harms, protection and recovery following regular cannabis use.” Translational psychiatry 6.1 (2016): e710.

About WoahStork

WoahStork is a marijuana app that allows you to order cannabis online from nearby dispensaries. Simply upload your government issued ID and doctor’s recommendation (if you’re looking for medical marijuana), and you’ll be able to place online orders for pickup or delivery within minutes! We also have a vast database of strains for you to review, compare prices, and order online!

If you don’t know where to start, our Strain Genie will give you a personalized strain recommendation for any medical ailment or recreational occasion!

The more you order and review, the more cannabis rewards you get – redeemable for steep discounts on cannabis from nearby dispensaries. WoahStork – the world’s best online cannabis store.

We combine products from all marijuana dispensaries in your area so you can buy cannabis sativa, cannabis indica, cannabis oil, weed brownies online legally. Finally the answer to the question “Where can I buy weed online legally” has finally been answered.

Have you recently been prescribed medical marijuana? Sure, it’s easy to find a cannabis dispensary near you, but how do you know which marijuana strains to try? If you are looking for the A+ cannabis strains or wondering which cannabis strain is best for you, then you’ve come to the right place! Use WoahStork to find the best weed strains and buy weed online.