Navigation Links
A gene related to aggression weakens the brain

National Institutes of Health's (NIH) National Institute of Mental Health (NIMH) researchers have found out that gene previously linked to impulsive violence appears// to weaken brain circuits that regulate impulses, emotional memory and thinking in humans.

It was studied through brain scans that revealed that people with this version of gene – especially males – tended to have relatively smaller emotion-related brain structures, a hyperactive alarm center and under-active impulse control circuitry.

This was reported by NIMH intramural researchers Andreas Meyer-Lindenberg, M.D., Daniel Weinberger, M.D., Ph.D., and colleagues in the Proceedings of the National Academy of Sciences during the week of March 20, 2006.

According to NIH Director Elias A. Zerhouni, M.D., who conducted MRI studies earlier in his career said, "These new findings illustrate the breathtaking power of 'imaging genomics' to study the brain's workings in a way that helps us to understand the circuitry underlying diversity in human temperament. By itself, this gene is likely to contribute only a small amount of risk in interaction with other genetic and psychosocial influences; it won't make people violent. But by studying its effects in a large sample of normal people, we were able to see how this gene variant biases the brain toward impulsive, aggressive behaviour."

The gene is one of two common versions that code for the enzyme monoamine oxydase-A (MAO-A), which breaks down key mood-regulating chemical messengers, most notably serotonin.

Structural MRI in 97 subjects was taken for the study and the results were that those with L showed reductions in gray matter (neurons and their connections) of about 8 percent in brain structures of a mood-regulating circuit (cingulate cortex, amygdala) among other areas. Volume of an area important for motivation and impulse regulation (orbital frontal cortex) was increased by 14 percent in men only. Altho ugh the reasons are unknown, this could reflect deficient pruning – the withering of unused neuronal connections as the brain matures and becomes more efficient, speculates Meyer-Lindenberg.

The researchers then looked at effects on brain activity using functional MRI (fMRI) scans. While performing a task matching emotionally evocative pictures – angry and fearful faces – subjects with L showed higher activity in the fear hub (amygdala). At the same time, decreased activity was observed in higher brain areas that regulate the fear hub (cingulate, orbital frontal, and insular cortices) – essentially the same circuit that was changed in volume.

Daniel Weinberger, M.D., Ph.D. said, "Heightened sensitivity in brain circuits important to cognitive inhibition and memory for negative emotional information may contribute to increased vulnerability of men with L exposed to abuse during childhood. Since only men showed gene effects in several of these circuits, this could lead to a situation where multiple brain control mechanisms are impaired and contribute to manifestly violent behavior, a kind of genetic double jeopardy."
br>
'"/>




Related medicine news :

1. Heart disease in the newborn is related to maternal malnutrition
2. Individuals with sleep related breathing disorders more prone to heart disease
3. Pharmaceutical giant offers AIDS related antifungal drug free to 50 countries
4. Pharmaceutical giant offers AIDS related antifungal drug free to 50 countries
5. Dampness related to asthma
6. Allergies are related to mothers menses
7. Genetic disorder related with sleep patterns
8. Energy intake directly related to portion size
9. Treatment for cholesterol-related illnesses likely with the discovery of receptor in mice
10. New Drug Shows Significant Improvement In HIV-related Heart Condition
11. Sleeping Less May be related to Weight Gain
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:6/27/2016)... ... June 27, 2016 , ... A revolution ... the emergency ambulance transport experience for the millions of people who require these ... disrupted the taxi industry through the use of technology. Now, SmartEMS has put ...
(Date:6/26/2016)... ... 2016 , ... On June 10-11, 2016, A Forever Recovery, a holistic treatment ... Longest Breakfast Table in Battle Creek, MI, where the rehabilitation facility is located. This ... of the world’s leading providers of cereal and other breakfast foods. Its residents often ...
(Date:6/26/2016)... ... June 26, 2016 , ... Brent Kasmer, a legally blind and certified personal trainer is helping ... fitness app. The fitness app plans to fix the two major problems leading the fitness ... size fits all type program , They don’t eliminate all the reasons people ...
(Date:6/25/2016)... ... June 25, 2016 , ... Austin residents seeking Mohs surgery services, can now ... and to Dr. Russell Peckham for medical and surgical dermatology. , Dr. Dorsey brings ... The selective fellowship in Mohs Micrographic Surgery completed by Dr. Dorsey was under the ...
(Date:6/25/2016)... Lewisville, TX (PRWEB) , ... June 25, 2016 , ... ... in the United States, named Dr. Sesan Ogunleye, as the Medical Director of its ... be the facility Medical Director of our new Mesquite location,” said Dr. James M. ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... , June 23, 2016 Bracket , a ... its next generation clinical outcomes platform, Bracket eCOA (SM) ... on June 26 – 30, 2016 in Philadelphia ... electronic Clinical Outcome Assessment product of its kind to fully ... Bracket eCOA 6.0 is a flexible platform for ...
(Date:6/23/2016)... June 23, 2016  Astellas today announced the establishment of Astellas Farma Colombia (AFC), a new affiliate with operations ... Latin America . ... ... ... ...
(Date:6/23/2016)... The vast majority of dialysis patients currently ... are usually 3 times a week, with treatment times ... time, equipment preparation and wait time.  This regimen can ... patients who are elderly and frail.  Many elderly dialysis ... centers for some duration of time. Residents ...
Breaking Medicine Technology: