Memory disorder diagnoses may benefit from seeing brain as networks

Date: Nov-04-2014 Looking at the brain as a highly interactive network of nodes, rather than a collection of individual areas of activity, could offer a new

way to diagnose the memory disorders that tend to affect older

people.

"By studying the brain as a network, we are, in a sense, adjusting our perspective - akin to examining the patterns that make up constellations of stars instead of focusing on each of the individual stars," says Prof. Wig.

This was the conclusion that researchers from the Center for Vital

Longevity (CVL) at the University of Texas (UT) at Dallas came to in a

study they reported in the Proceedings of the National Academy of

Sciences (PNAS).

Gagan Wig, assistant professor in the UT Dallas School of Behavioral and

Brain Sciences, and colleagues examined how brain areas talk to each other

to form brain networks and how these change with age.

Prof. Wig says brain networks are not unlike social and technological

networks; they comprise groups of highly interactive nodes, and:

"These nodes all communicate with one another in a large-scale brain

network. A considerable amount of research has highlighted how older adults

use different brain areas than younger adults when performing the same

tasks."

He explains that their approach offers an alternative way to evaluate

the differences between the younger and the older brain that focuses on the

brain as a network.

"By studying the brain as a network, we are, in a sense, adjusting our

perspective - akin to examining the patterns that make up constellations of

stars instead of focusing on each of the individual stars," he adds.

The older the brain, the less segregated the sub-networks

For their study, Prof. Wig and colleagues looked at how separate sub-networks of the brain come together to operate specialized functions.

They found that the older the brain, the less segregated the sub-networks.

They also found that less segregation was more strongly tied to poorer

long-term memory, independent of age.

Prof. Wig suggests perhaps measuring the extent of segregation among the

brain's sub-networks could be a way to predict memory decline.

The team examined data from the Dallas Lifespan Brain Study. The data they

analyzed came from 210 healthy adults aged between 20 and 89 who completed

assessments of thinking and memory.

The participants also underwent brain scans while they were thinking of

nothing in particular. The brain scans were used as a measure of brain

connectivity.

To analyze the results, the researchers looked at the brain connections from a

network point of view. To do this, they used graph theory - an area of

mathematics that is used for studying traffic flows, disease spread and

social networks, such as Facebook.

They found the brain networks in the younger brains tended to show lots

of connections within the networks that are associated with processing of

specific tasks, and fewer connections that aid communication between

networks.

But this distinction was less noticeable in the older brain. Prof. Wig

says they found that segregation between brain networks reduced as age

increased.

Funding for the study came from the National Institute on Aging, a part of

the National Institutes of Health.

In another recently published study, Medical News Today learned

how researchers found that injury to brain hubs

does more damage. They showed how damage to brain hubs disrupts

people's capacity to think and adapt to everyday challenges more severely

than damage to locations that are distant from hubs.

Written by Catharine Paddock PhD

Not to be reproduced without permission.

Follow @twitter

window.twttr = (function (d, s, id) {
var t, js, fjs = d.getElementsByTagName(s)[0];
if (d.getElementById(id)) return;
js = d.createElement(s); js.id = id;
js.src= "https://platform.twitter.com/widgets.js";
fjs.parentNode.insertBefore(js, fjs);
return window.twttr || (t = { _e: [], ready: function (f) { t._e.push(f) }
}(document, "script", "twitter-wjs"));

Courtesy: Medical News Today Note: Any medical information available in this news section is not intended as a substitute for informed medical advice and you should not take any action before consulting with a health care professional.