Featured Research

from universities, journals, and other organizations

Nonconcussion head impacts in contact sports linked to brain changes and lower test scores

Date:
December 11, 2013
Source:
Indiana University
Summary:
Repeated blows to the head during a season of contact sports may cause changes in the brain's white matter and affect cognitive abilities even if none of the impacts resulted in a concussion.

Credit: Actionpics / Fotolia

Repeated blows to the head during a season of contact sports may cause changes in the brain's white matter and affect cognitive abilities even if none of the impacts resulted in a concussion, according to a study published today in the journal Neurology.

Using a form of magnetic resonance imaging, or MRI, researchers at the Indiana University School of Medicine and the Geisel School of Medicine at Dartmouth College found significant differences in brain white matter of varsity football and hockey players compared with a group of noncontact-sport athletes following one season of competition. White matter is composed primarily of axons, the long fibers that transmit signals between neurons.

"The contact sports and noncontact-sports groups differed, and the number of times the contact sports participants were hit, and the magnitude of the hits they sustained, were correlated with changes in the white matter measures," said Thomas W. McAllister, M.D., chair of the IU Department of Psychiatry.

"In addition, there was a group of contact sports athletes who didn't do as well as predicted on tests of learning and memory at the end of the season, and we found that the amount of change in the white matter measures was greater in this group," Dr. McAllister said.

The study was conducted while Dr. McAllister was Millennium Professor of Psychiatry at Dartmouth.

"This study raises the question of whether we should look not only at concussions but also the number of times athletes receive blows to the head and the magnitude of those blows, whether or not they are diagnosed with a concussion," Dr. McAllister said.

Two groups of Dartmouth athletes were studied: 80 football and ice hockey players in the contact sports group, and 79 athletes drawn from such noncontact sports as track, crew and Nordic skiing. The football and hockey players wore helmets equipped with accelerometers, which enabled the researchers to compile the number and severity of impacts to their heads. Players who sustained a concussion during the season were not included in the analysis.

The athletes were administered a form of MRI test known as diffusion tensor imaging, which is used to measure the integrity of the white matter. They were also given the California Verbal Learning Test II, a measure of verbal learning and memory.

The study did not find "large-scale, systematic differences" in the brain scan measures at the end of the season, which the authors found "somewhat reassuring" and consistent with the fact that thousands of individuals have played contact sports for many years without developing progressive neurodegenerative disorders.

However, the results do suggest that some athletes may be more susceptible to repeated head impacts that do not involve concussions, although much more research would be necessary to determine how to identify those athletes.

More work would also be necessary to determine whether the effects of the head impacts are long-lasting or permanent, and whether they are cumulative.


Story Source:

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


Journal Reference:

  1. Thomas W. McAllister, James C. Ford, Laura A. Flashman, Arthur Maerlender, Richard M. Greenwald, Jonathan G. Beckwith, Richard P. Bolander, Tor D. Tosteson, John H. Turco, Rema Raman, and Sonia Jain. Effect of head impacts on diffusivity measures in a cohort of collegiate contact sport athletes. Neurology, 2013 DOI: 10.1212/01.wnl.0000438220.16190

Cite This Page:

Indiana University. "Nonconcussion head impacts in contact sports linked to brain changes and lower test scores." ScienceDaily. ScienceDaily, 11 December 2013. <www.sciencedaily.com/releases/2013/12/131211185554.htm>.
Indiana University. (2013, December 11). Nonconcussion head impacts in contact sports linked to brain changes and lower test scores. ScienceDaily. Retrieved September 17, 2014 from www.sciencedaily.com/releases/2013/12/131211185554.htm
Indiana University. "Nonconcussion head impacts in contact sports linked to brain changes and lower test scores." ScienceDaily. www.sciencedaily.com/releases/2013/12/131211185554.htm (accessed September 17, 2014).

Share This



More Science & Society News

Wednesday, September 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Some Tobacco Farmers Thrive Amid Challenges

Some Tobacco Farmers Thrive Amid Challenges

AP (Sep. 16, 2014) The South's tobacco country is surviving, and even thriving in some cases, as demand overseas keeps growers in the fields of one of America's oldest cash crops. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Space Race Pits Bezos Vs Musk

Space Race Pits Bezos Vs Musk

Reuters - Business Video Online (Sep. 16, 2014) Amazon CEO Jeff Bezos' startup will team up with Boeing and Lockheed to develop rocket engines as Elon Musk races to have his rockets certified. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
President To Send 3,000 Military Personnel To Fight Ebola

President To Send 3,000 Military Personnel To Fight Ebola

Newsy (Sep. 16, 2014) President Obama is expected to send 3,000 troops to West Africa as part of the effort to contain Ebola's spread. Video provided by Newsy
Powered by NewsLook.com
Obama Orders Military Response to Ebola

Obama Orders Military Response to Ebola

AP (Sep. 16, 2014) Calling the Ebola outbreak in West Africa a potential threat to global security, President Barack Obama is ordering 3,000 U.S. military personnel to the stricken region amid worries that the outbreak is spiraling out of control. (Sept. 16) Video provided by AP
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