Featured Research

from universities, journals, and other organizations

New Imaging Technique Discovers Differences In Brains Of People With Autism

Date:
October 24, 2006
Source:
Carnegie Mellon University
Summary:
Using a new form of brain imaging known as diffusion tensor imaging (DTI), researchers in the Center for Cognitive Brain Imaging at Carnegie Mellon University have discovered that the so-called white matter in the brains of people with autism has lower structural integrity than in the brains of normal individuals. This provides further evidence that the anatomical differences characterizing the brains of people with autism are related to the way those brains process information.

Using a new form of brain imaging known as diffusion tensor imaging (DTI), researchers in the Center for Cognitive Brain Imaging at Carnegie Mellon University have discovered that the so-called white matter in the brains of people with autism has lower structural integrity than in the brains of normal individuals. This provides further evidence that the anatomical differences characterizing the brains of people with autism are related to the way those brains process information.

The results of this latest study were published in the journal NeuroReport. The scientists used DTI — which tracks the movement of water through brain tissue — to measure the structural integrity of the white matter that acts as cables to wire the parts of the brain together. Normally, water molecules move, or diffuse, in a direction parallel to the orientation of the nerve fibers of the white matter. They're aided by the coherent structure of the fibers and a process called myelination, in which a sheath is formed around the fibers that speeds nerve impulses. The movement of water is more dispersed if the structural integrity of the tissue is low — i.e., if the fibers are less dense, less coherently organized, or less myelinated — as it was with the participants with autism in the Carnegie Mellon study. Researchers found this dispersed pattern particularly in areas in and around the corpus callosum, the large band of nerve fibers that connects the two hemispheres of the brain.

"These reductions in white matter integrity may underlie the behavioral pattern observed in autism of narrowly focused thought and weak coherence of different streams of thought," said Marcel Just, director of the Center for Cognitive Brain Imaging and a co-author of the latest study. "The new findings also provide supporting evidence for a new theory of autism that attributes the disorder to underconnectivity among brain regions," Just said.

In 2004, Just and his colleagues proposed the underconnectivity theory based on a groundbreaking study in which they discovered abnormalities in the white matter that suggested a lack of coordination among brain areas in people with autism. This theory helps explain a paradox of autism: Some people with autism have normal or even superior skills in some areas, while many other types of thinking are disordered.

Last summer, Just led a team of researchers that found for the first time that the abnormality in synchronization among brain areas is related to the abnormality in the white matter. They discovered that key portions of the corpus callosum seem to play a role in the limitation on synchronization. In people with autism, anatomical connectivity — based on the size of the white matter — was found to be positively correlated with functional connectivity, which is the synchronization of the active brain regions. They also found that the functional connectivity was lower in those participants in whom the autism was more severe.

These studies, along with the latest paper, are providing a comprehensive picture of the autistic brain, whose components operate with less coordination than is normally the case, and which is less reliant on frontal components and more reliant on posterior components. The latest DTI finding shows that some of the frontal-posterior communication fiber tracts are abnormal, consistent with the lower degree of frontal-posterior coordination.

"The brain components in autism function more like a jam session and less like a symphony," Just said.

The latest study was co-authored by Rajesh K. Kana and Timothy A. Keller of the Center for Cognitive Brain Imaging. This research was supported by the National Institute of Child Health and Human Development.


Story Source:

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


Cite This Page:

Carnegie Mellon University. "New Imaging Technique Discovers Differences In Brains Of People With Autism." ScienceDaily. ScienceDaily, 24 October 2006. <www.sciencedaily.com/releases/2006/10/061023192716.htm>.
Carnegie Mellon University. (2006, October 24). New Imaging Technique Discovers Differences In Brains Of People With Autism. ScienceDaily. Retrieved September 16, 2014 from www.sciencedaily.com/releases/2006/10/061023192716.htm
Carnegie Mellon University. "New Imaging Technique Discovers Differences In Brains Of People With Autism." ScienceDaily. www.sciencedaily.com/releases/2006/10/061023192716.htm (accessed September 16, 2014).

Share This



More Mind & Brain News

Tuesday, September 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

FDA Eyes Skin Shocks Used at Mass. School

FDA Eyes Skin Shocks Used at Mass. School

AP (Sep. 15, 2014) The FDA is considering whether to ban devices used by the Judge Rotenberg Educational Center in Canton, Massachusetts, the only place in the country known to use electrical skin shocks as aversive conditioning for aggressive patients. (Sept. 15) Video provided by AP
Powered by NewsLook.com
Shocker: Journalists Are Utterly Addicted To Coffee

Shocker: Journalists Are Utterly Addicted To Coffee

Newsy (Sep. 13, 2014) A U.K. survey found that journalists consumed the most amount of coffee, but that's only the tip of the coffee-related statistics iceberg. Video provided by Newsy
Powered by NewsLook.com
'Magic Mushrooms' Could Help Smokers Quit

'Magic Mushrooms' Could Help Smokers Quit

Newsy (Sep. 11, 2014) In a small study, researchers found that the majority of long-time smokers quit after taking psilocybin pills and undergoing therapy sessions. Video provided by Newsy
Powered by NewsLook.com
'Fat Shaming' Might Actually Cause Weight Gain

'Fat Shaming' Might Actually Cause Weight Gain

Newsy (Sep. 11, 2014) A study for University College London suggests obese people who are discriminated against gain more weight than those who are not. 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