Pinpointing the framing effect

Context matters in perception and behavior. It has long been known, for instance, that people told how they might gain from a decision are more inclined to avoid risk than people told what they might lose. This is so even when the facts in both accounts are logically the same. (The study of such ``heuristic bias'' was part of the work for which Daniel Kahneman of Princeton won the Nobel Prize in Economics in 2002.) For example, people told ``you'll be given $50 and get to keep $20,'' are more averse to a gamble than people told ``you'll lose $30.''

This paper in Science by Benedetto De Martino,* Dharshan Kumaran, Ben Seymour, Raymond J. Dolan, ties this familiar result from economics to brain scans. De Martino and his colleagues put the $50 question to students (actually, they used pounds, but the currency doesn't matter) and scanned their brains as they thought and felt their way to a decision.

Their results suggest that the source of the heuristic bias is activity in the amygdala, the brain region associated with aroused attention to important or dangerous perceptions.

It's one more example of work that links different levels of analysis -- mind to brain, economics to neural firing. The amygdala has also been implicated in racial bias as well as heuristic bias.