investment, brain lesions, and risk games

being brain-damaged may not be so bad after all. in a study from this month's psychological science, participants with focal lesions in emotion centers made better decisions when presented with risky investment tasks. the emotional brain has been chided for making myopic, risky decisions, but here it seems it’s the unemotional brain taking all the risks, and for the better.

the task at hand was a positive-expected-value investment game, which means that benefits outweigh the costs of playing. even though rationally it made more sense to bet, normal and control patients became more conservative with each round. in contrast, lesioned participants bet at approximately the same risk level throughout. as the risk of loosing was low, "risky" decisions paid off, and lesioned participants made off with more winnings.

because most dilemmas are not positive-expected-value, and have more ambiguous elements, this study lacks immediate practical application. emotions can play a valuable role in many decision-making processes, particularly where ambiguity is involved. however, it is important to note when emotion is a good, or bad, guide for decisions - something this study helps to do.

source: baba shiv et al."investment behavior and the negative side of emotion." psychological science june 2005.

Labels: decision making, neuroscience