Featured Research

from universities, journals, and other organizations

Marijuana Use Affects Blood Flow In Brain Even After Abstinence

Date:
February 13, 2005
Source:
American Academy Of Neurology
Summary:
People who smoked marijuana had changes in the blood flow in their brains even after a month of not smoking, according to a study published in the February 8 issue of Neurology, the scientific journal of the American Academy of Neurology.

ST. PAUL, Minn. – People who smoked marijuana had changes in the blood flow in their brains even after a month of not smoking, according to a study published in the February 8 issue of Neurology, the scientific journal of the American Academy of Neurology.

The findings could explain in part the problems with thinking or remembering found in other studies of marijuana users, according to study authors Ronald Herning, PhD, and Jean Lud Cadet, MD, of the National Institute on Drug Abuse in Baltimore, Md.

The study involved 54 marijuana users and 18 control subjects. The marijuana users volunteered to take part in a month-long inpatient program. The blood flow velocity in brain arteries was tested with transcranial Doppler sonography in all participants at the beginning of the study and again at the end of the month for the marijuana users.

The blood flow velocity was significantly higher in the marijuana users than in the control subjects, both at the beginning of the study and after a month of abstinence from marijuana use. The marijuana users also had higher values on the pulsatility index (PI), which measures the amount of resistance to blood flow. This is thought to be due to narrowing of the blood vessels that occurs when the circulation system's ability to regulate itself is impaired.

"The marijuana users had PI values that were somewhat higher than those of people with chronic high blood pressure and diabetes," Herning said. "However, their values were lower than those of people with dementia. This suggests that marijuana use leads to abnormalities in the small blood vessels in the brain, because similar PI values have been seen in other diseases that affect the small blood vessels."

The PI values for light and moderate marijuana users improved over the month of abstinence. There was no improvement for heavy marijuana users. The light users smoked two to 15 joints per week. The moderate users smoked 17 to 70 joints per week, and the heavy users smoked 78 to 350 joints per week.

###

The American Academy of Neurology, an association of more than 18,000 neurologists and neuroscience professionals, is dedicated to improving patient care through education and research. A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as stroke, Alzheimer's disease, epilepsy, Parkinson's disease, and multiple sclerosis.

For more information about the American Academy of Neurology, visit its Website at http://www.aan.com.


Story Source:

The above story is based on materials provided by American Academy Of Neurology. Note: Materials may be edited for content and length.


Cite This Page:

American Academy Of Neurology. "Marijuana Use Affects Blood Flow In Brain Even After Abstinence." ScienceDaily. ScienceDaily, 13 February 2005. <www.sciencedaily.com/releases/2005/02/050211084701.htm>.
American Academy Of Neurology. (2005, February 13). Marijuana Use Affects Blood Flow In Brain Even After Abstinence. ScienceDaily. Retrieved August 1, 2014 from www.sciencedaily.com/releases/2005/02/050211084701.htm
American Academy Of Neurology. "Marijuana Use Affects Blood Flow In Brain Even After Abstinence." ScienceDaily. www.sciencedaily.com/releases/2005/02/050211084701.htm (accessed August 1, 2014).

Share This




More Mind & Brain News

Friday, August 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Dieting At A Young Age Might Lead To Harmful Health Habits

Dieting At A Young Age Might Lead To Harmful Health Habits

Newsy (July 30, 2014) Researchers say women who diet at a young age are at greater risk of developing harmful health habits, including eating disorders and alcohol abuse. Video provided by Newsy
Powered by NewsLook.com
It's Not Just Facebook: OKCupid Experiments With Users Too

It's Not Just Facebook: OKCupid Experiments With Users Too

Newsy (July 29, 2014) If you've been looking for love online, there's a chance somebody has been looking at how you're looking. Video provided by Newsy
Powered by NewsLook.com
How Your Face Can Leave A Good Or Bad First Impression

How Your Face Can Leave A Good Or Bad First Impression

Newsy (July 29, 2014) Researchers have found certain facial features can make us seem more attractive or trustworthy. Video provided by Newsy
Powered by NewsLook.com
Losing Sleep Leaves You Vulnerable To 'False Memories'

Losing Sleep Leaves You Vulnerable To 'False Memories'

Newsy (July 27, 2014) A new study shows sleep deprivation can make it harder for people to remember specific details of an event. 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