Featured Research

from universities, journals, and other organizations

Human study shows greater cognitive deficits in marijuana users who start young

Date:
November 17, 2010
Source:
Society for Neuroscience
Summary:
New research shows that people who start using marijuana at a young age and those who use the greatest amount of marijuana may be the most cognitively impaired.

New research shows that people who start using marijuana at a young age and those who use the greatest amount of marijuana may be the most cognitively impaired.

The research was presented at Neuroscience 2010, the annual meeting of the Society for Neuroscience, held in San Diego.

Marijuana users show deficits in the ability to switch behavioral responses according to the context of a situation, also known as cognitive flexibility. The new study, directed by Staci Gruber, PhD, at McLean Hospital and Harvard Medical School, compared people's performance on the Wisconsin Card Sorting Task, a test of cognitive flexibility. During the task, people are shown four shown cards that differ in color, symbol, and value. Based on the rules they glean from these displayed cards, they must then sort a deck of cards. The participants are not told what the rules are -- only whether their sorting attempt is correct or incorrect. During the test, the researchers change the rules without warning, and participants must adjust accordingly. How a participant responds is a strong indicator of cognitive flexibility.

The researchers found that habitual marijuana users made repeated errors despite feedback that they were wrong. Marijuana users also had more difficulty maintaining a set of rules, suggesting an inability to maintain focus. Those participants who began using marijuana before the age of 16 and those who used the most marijuana showed the greatest impairment.

"Our results provide further evidence that marijuana use has a direct effect on executive function, and that both age of onset and magnitude of marijuana use can significantly influence cognitive processing," said Gruber. "Given the prevalence of marijuana use in the United States, these findings underscore the importance of establishing effective strategies to decrease marijuana use, especially in younger populations," she said.

Research was supported by the National Institute on Drug Abuse.


Story Source:

The above story is based on materials provided by Society for Neuroscience. Note: Materials may be edited for content and length.


Cite This Page:

Society for Neuroscience. "Human study shows greater cognitive deficits in marijuana users who start young." ScienceDaily. ScienceDaily, 17 November 2010. <www.sciencedaily.com/releases/2010/11/101116104202.htm>.
Society for Neuroscience. (2010, November 17). Human study shows greater cognitive deficits in marijuana users who start young. ScienceDaily. Retrieved August 20, 2014 from www.sciencedaily.com/releases/2010/11/101116104202.htm
Society for Neuroscience. "Human study shows greater cognitive deficits in marijuana users who start young." ScienceDaily. www.sciencedaily.com/releases/2010/11/101116104202.htm (accessed August 20, 2014).

Share This




More Mind & Brain News

Wednesday, August 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Charter Schools Alter Post-Katrina Landscape

Charter Schools Alter Post-Katrina Landscape

AP (Aug. 20, 2014) Nine years after Hurricane Katrina, charter schools are the new reality of public education in New Orleans. The state of Louisiana took over most of the city's public schools after the killer storm in 2005. (Aug. 20) Video provided by AP
Powered by NewsLook.com
Researcher Testing on-Field Concussion Scanners

Researcher Testing on-Field Concussion Scanners

AP (Aug. 19, 2014) Four Texas high school football programs are trying out an experimental system designed to diagnose concussions on the field. The technology is in response to growing concern over head trauma in America's most watched sport. (Aug. 19) Video provided by AP
Powered by NewsLook.com
Kids' Drawings At Age 4 Linked To Intelligence At Age 14

Kids' Drawings At Age 4 Linked To Intelligence At Age 14

Newsy (Aug. 19, 2014) A study by King's College London says there's a link between how well kids draw at age 4 and how intelligent they are later in life. Video provided by Newsy
Powered by NewsLook.com
Mental, Neurological Disabilities Up 21% Among Kids

Mental, Neurological Disabilities Up 21% Among Kids

Newsy (Aug. 18, 2014) New numbers show a decade's worth of changes in the number of kids with disabilities. They suggest mental disabilities are up; physical ones are down. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins