```` A study published in ``Psychological Science`` co-authored by professors at Stanford University, Carnegie Mellon University and University of Iowa pitted people with normal brains against people whose limbic systems, the brain`s emotional center, were impaired.

The paper asks whether a neural systems dysfunction that curbs emotion can lead, in some circumstances, to more advantageous decisions. The answer, in terms of investing, was yes.

Subjects were given $20 in play money to invest, $1 at a time. Determining whether the investor won or lost was done by coin toss. Heads, they won; tails they lost.

Losers lost the dollar they had invested. Winners had $2.50 added to their account. The rational thing to do, since there`s a 50-50 chance of the coin coming up heads each time and the returns for winning were greater than the returns for losing, would be to invest in every round. But people with normal brains did not behave rationally. They became more conservative when they lost. People with impaired limbic systems did not.

``Medical study confirms brain impairment HELPS improve investment returns,`` Ajay Singh Kapur, chief global equity strategist at Citigroup, wrote in a summary of the study.````

-z