Washington, April 27 (ANI): People more driven by rewards win most often, even when there is no reward at stake, according to a new study.
To reach the conclusion, neuroscientists at Washington University in St. Louis tested 31 randomly selected subjects with word games, some of which had monetary rewards of either 25 or 75 cents per correct answer, others of which had no money attached.
Subjects were given a short list of five words to memorize in a matter of seconds, then a 3.5-second interval or pause, then a few seconds to respond to a solitary word that either had been on the list or had not.
Test performance had no consequence in some trials, but in others, a computer graded the responses, providing an opportunity to win either 25 cent or 75 cents for quick and accurate answers.
Even during these periods, subjects were sometimes alerted that their performance would not be rewarded on that trial.
Prior to testing, subjects were submitted to a battery of personality tests that rated their degree of competitiveness and their sensitivity to monetary rewards.
The study was designed to test the hypothesis that excitement in the brains of the most monetary-reward-sensitive subjects would slacken during trials that did not pay.
However, the researchers found a paradoxical result: the performance of the most reward-driven individuals was actually most improved - relative to the less reward-driven - in the trials that paid nothing, not the ones in which there was money at stake.
Even more striking was that the brain scans taken using functional Magnetic Resonance Imaging (fMRI) showed a change in the pattern of activity during the non-rewarded trials within the lateral prefrontal cortex (PFC), located right behind the outer corner of the eyebrow, an area that is strongly linked to intelligence, goal-driven behavior and cognitive strategies.
The change in lateral PFC activity was statistically linked to the extra behavioural benefits observed in the reward-driven individuals.
The researchers suggest that this change in lateral PFC activity patterns represents a flexible shift in response to the motivational importance of the task, translating this into a superior task strategy that the researchers term "proactive cognitive control."
In other words, once the rewarding motivational context is established in the brain indicating there is a goal-driven contest at hand, the brain actually rallies its neuronal troops and readies itself for the next trial, whether it's for money or not.
The results were published April 26 in the early online edition of the Proceedings of the National Academy of Science. (ANI)