October 9, 2003. Copyright 2002. Graphic News. All rights reserved.

Bruised egos and stubbed toes

LONDON, October 9, Graphic News: A social snub or a smack on the nose can generate similar responses in the human brain, according to a new study employing fMRI (functional Magnetic Resonance Imaging) technology.

Patterns of brain activity during social exclusion are similar to those found in physical pain studies, according to Naomi Eisenberger of the University of California, Los Angeles and colleagues at Macquarie University, Sydney, Australia. The scientists studied players who participated in a video ball game that led them to feel social inclusion and both unintentional and intentional social exclusion. 

The subjects controlled a hand at the bottom of a video screen which could be used to throw a virtual ball to two other figures at the top of the screen. Although the study participants were told other live people commanded these animated figures, they were actually controlled by a computer programme.

The players experienced three different social situations. First, they experienced ÒnobodyÕs faultÓ social exclusion when they had to watch the two top players throw the ball back and forth. They couldnÕt join in because of fake technical difficulties. Next, the test subject got to play. After playing happily for a while, the two ÒplayersÓ started throwing the ball to each other and excluded the person controlling the hand. 

The researchers used fMRI to create high resolution moving pictures of brain activity. fMRI uses a large magnet to induce chemical elements in fats and water in the brain to emit distinctive radio signals. These signals allow brain blood flow to be tracked -- the more active a brain area is, the more blood flows to it. Thus, fMRI can provide a moment-by-moment movie of brain activity.

The team report that a part of the brain, the anterior cingulate cortex -- a region known to be involved in the processing of physical pain; and emotionally-driven behaviour including, possibly, falling in love -- is activated during both kinds of exclusion. In addition, a nearby region of the brain known to manage or regulate distress, the right ventral prefrontal cortex, was only activated in the explicit social exclusion but not the ÒnobodyÕs faultÓ exclusion scenario. 

The authors suggest that explicit awareness of exclusion changes the way the human brain responds. The hurt from getting punched or ignored at lunch comes, in part, from the same part of the brain.
/ENDS

Sources: Science, University College London, National Institute of Mental Health