Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Brain abnormality found in boys with attention deficit hyperactivity disorder

19.03.2009
Researchers trying to uncover the mechanisms that cause attention deficit hyperactivity disorder and conduct disorder have found an abnormality in the brains of adolescent boys suffering from the conditions, but not where they expected to find it.

Boys with either or both of these disorders exhibited a different pattern of brain activity than normally developing boys when they played a simple game that sometimes gave them a monetary reward for correct answers, according to a new study by a University of Washington research team.

The research focused on two brain areas, the striatum and anterior cingulate cortex. The striatal region is a network of structures in the mid brain that motivates people to engage in pleasurable or rewarding behavior. The anterior cingulate is higher in the brain and normally activates when an expected reward stops. However, this process, called extinction, doesn't occur, at least as quickly, in boys with attention deficit hyperactivity or conduct disorders. Instead, the striatal region continues to be activated, said Theodore Beauchaine, a UW associate professor of psychology and senior author of the paper.

"When children engage in impulsive behavior they are looking to stimulate themselves and have fun. Children with attention deficit hyperactivity disorder are always looking to have fun and that is what gets them in trouble," he said. "A behavior should stop when the reward stops. When you stop the reward for children with these disorders, they continue to focus on the reward long afterward and the anterior cingulate does not appear to become activated."

Attention deficit hyperactivity disorder is one of the most common mental disorders among children, affecting between 3 and 5 percent of school-age youngsters, or an estimated 2 million.

The researchers used functional magnetic resonance imaging to compare brain activity in 19 boys with either or both disorders and 11 normally developing boys. The adolescents ranged in age from 12 to 16.

Their brains were scanned while they played the game. The boys looked at a screen and there was a button under each of their thumbs. When a light flashed on the left or right side of the screen they were instructed to press the button on that side. The screen lit up very fast, up to 100 times a minute. The boys received five cents for each correct response and could win up to $50. They were not penalized for wrong answers and their accumulated winnings showed up on the screen.

Each boy had four five-minute blocks of trials. The first and third trials involved opportunities to earn money. The second and fourth trials did not involve winning money, but the boys were told to keep playing the game because the game would change at some point.

Beauchaine said there was no difference in the accuracy or speed – the behavioral response – between the two groups. But there was a difference in brain activation. When the non-reward blocks came up the anterior cingulate lit up for normally developing boys, but those with either of the disorders, which frequently co-occur, continued to only show activation in the striatum.

"This shows there is an abnormality, but not in the place we expected to find it. We expected to find a difference in the way the striatum functions, but instead found it in anterior cingulate functioning," said Beauchaine.

Joel Schwarz | EurekAlert!
Further information:
http://www.washington.edu

More articles from Health and Medicine:

nachricht Organ-on-a-chip mimics heart's biomechanical properties
23.02.2017 | Vanderbilt University

nachricht Researchers identify cause of hereditary skeletal muscle disorder
22.02.2017 | Klinikum der Universität München

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>