--- title: How Smoking Pot May Hurt the Teenage Brain description: The latest study on recreational pot focuses on how marijuana affects thinking in teens and young adults. canonical: https://time.com/5243934/smoking-pot-teenage-brain/ author: Alice Park article:opinion: false article:content_tier: free article:published_time: 2018-04-18T15:00:30.000Z article:modified_time: 2026-02-23T20:00:06.868Z article:section: Health og:title: How Smoking Pot May Hurt the Teenage Brain og:description: Young people who used marijuana tended to have lower scores on memory tests og:url: https://time.com/5243934/smoking-pot-teenage-brain/ og:site_name: TIME og:image: https://static.time.com/v3/assets/bltea6093859af6183b/blt48957ab0132e0739/69892de7ab6d7767a86b2664/gettyimages-769715421.jpg?branch=production&width=3840&quality=75&auto=webp&crop=16:9 og:image:width: 1200 og:image:height: 675 og:image:alt: Close-up of marijuana plant growing outdoors og:type: article twitter:card: summary_large_image twitter:title: How Smoking Pot May Hurt the Teenage Brain twitter:description: Young people who used marijuana tended to have lower scores on memory tests twitter:image: https://static.time.com/v3/assets/bltea6093859af6183b/blt48957ab0132e0739/69892de7ab6d7767a86b2664/gettyimages-769715421.jpg?branch=production&width=3840&quality=75&auto=webp&crop=16:9 ---  # How Smoking Pot May Hurt the Teenage Brain  by [Alice Park](https://time.com/author/alice-park/)  ## Alice Park Senior Correspondent Apr 18, 2018 3:00 PM UTC  Norman Posselt—Getty Images/fStop  by [Alice Park](https://time.com/author/alice-park/)  ## Alice Park Senior Correspondent Apr 18, 2018 3:00 PM UTC As access to legal marijuana continues to expand, both for [recreational](http://time.com/5090018/americans-support-legalizing-marijuana/) and [medical uses](http://time.com/4455098/medical-marijuana-justice-department-courts/), researchers say there are still plenty of [unanswered questions](http://time.com/3693530/marijuana-health-colorado-pregnant/) about how increased use might affect the still-developing brains of adolescents and young adults. Studies so far have found that marijuana can affect short-term thinking skills in adults, including attention, memory and other higher cognitive functions. In the latest review of the studies on younger people, scientists found similar effects, but also revealed some surprising hints about how lasting those effects might be. In a [study published in _JAMA Psychiatry_](http://jamanetwork.com/journals/jamapsychiatry/fullarticle/10.1001/jamapsychiatry.2018.0335), J. Cobb Scott, an assistant professor of psychiatry at the Perelman School of Medicine at the University of Pennsylvania, and his colleagues analyzed 69 studies involving younger cannabis users. They found that compared to non-users, those who used marijuana frequently were more likely to have slightly lower scores on tests of memory, learning new information and higher level thinking involving problem solving and processing information. But these effects seemed to wane if the users stopped using marijuana for about three days. “That was the biggest surprise,” says Scott. “There is biological plausibility that cannabis could cause changes in the brain that is still developing. But the abstinence data we have indicates that while those effects are detectable, they seem to go away after more than three days of abstinence.” The study could not assess whether doses of [medicinal marijuana](http://time.com/4080110/dea-medical-marijuana-california-ruling/) led to similar changes in cognitive skills; the study only included recreational users, and Scott says that medicinal forms may vary from recreational forms of cannabis. Scott notes that the results, particularly the findings about abstinence, shouldn’t be interpreted as absolving marijuana from potential cognitive deficits. “We can’t determine causality,” he says. “These results are another piece of the puzzle to consider in evaluating the risks versus potential benefits of cannabis. It’s not the final say, and we still have a lot to learn about the longer-term effects of heavy cannabis use on brain and behavior.” ```json [{"@context":"https://schema.org","@type":"NewsArticle","@id":"https://time.com/5243934/smoking-pot-teenage-brain/","mainEntityOfPage":{"@type":"WebPage","@id":"https://time.com/5243934/smoking-pot-teenage-brain/"},"headline":"How Smoking Pot May Hurt the Teenage Brain","datePublished":"2018-04-18T15:00:30.000Z","dateModified":"2026-02-23T20:00:06.868Z","description":"Young people who used marijuana tended to have lower scores on memory tests","url":"https://time.com/5243934/smoking-pot-teenage-brain/","keywords":["Brain","healthytime"],"thumbnailUrl":"https://static.time.com/v3/assets/bltea6093859af6183b/blt48957ab0132e0739/69892de7ab6d7767a86b2664/gettyimages-769715421.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","author":[{"@type":"Person","name":"Alice Park","jobTitle":"Senior Correspondent","url":"https://time.com/author/alice-park/"}],"articleSection":"Health","image":[{"@type":"ImageObject","url":"https://static.time.com/v3/assets/bltea6093859af6183b/blt48957ab0132e0739/69892de7ab6d7767a86b2664/gettyimages-769715421.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","width":1200,"height":675,"headline":"Close-up of marijuana plant growing outdoors","caption":"Close-up of marijuana plant growing outdoors","creditText":"Norman Posselt—Getty Images/fStop","representativeOfPage":true}],"publisher":{"@type":"Organization","name":"Time","url":"https://time.com/","logo":{"@type":"ImageObject","url":"https://time.com/images/logo.png","width":528,"height":156},"foundingDate":"March 3, 1923","sameAs":["https://www.facebook.com/time","https://www.instagram.com/time/?hl=en","https://twitter.com/time","https://www.pinterest.com/timemagazine"]}},{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/section/health/","name":"Health"}},{"@type":"ListItem","position":2,"item":{"@id":"/tag/brain/","name":"Brain"}},{"@type":"ListItem","position":3,"item":{"@id":"https://time.com/5243934/smoking-pot-teenage-brain/","name":"How Smoking Pot May Hurt the Teenage Brain"}}]}] ```