Thursday, May 04, 2006

the neuroeconomics of dread

Neuroeconomics is an interesting new field at the intersection of neuroscience, psychology, and behavioral economics. It's the study of how decision making, and in particular decisions about risk, reward, and punishment, is implemented in the brain. Neuroeconomists try to figure out what parts of your brain and what biochemicals are involved when you (for example) weigh a guaranteed small reward and a chance at a larger reward. A lot has been learned over the last couple of decades.

A new study out in Science looks at an interesting phenomenon--getting bad experiences over with sooner rather than later. With rewards, it's usually better to have a reward earlier rather than later, and that may be true even if the later reward is larger. Would you rather I gave you $100 now or $200 in 15 years? Probably the $100 now, as who knows what might happen between now and then!

It turns out dread is kinda paradoxical, at least for some people. A punishment (like, say, an electric shock to the soles of your feet) is a negative reward. All things being equal, you would assume that you'd rather get a negative reward later rather than sooner, just the opposite of a positive reward. But that's not always the case. In the new study by researchers at Emory University, participants were given a choice of a large immediate shock or a somewhat smaller, but still painful shock after a delay. If everything is equal, the smaller shock later would be definitely preferable, but a substantial portion of the set of participants (9 of 32) chose the larger immediate shock. The only way this makes any sense is if the sense of dread you feel as you wait... wait... wait for the shock is equivalent to a punishment.

And, with the help of fMRI brain scans, that's what they found. The subjects were scanned while being told that a shock was coming after a certain amount of time. For the participants who would prefer the immediate shocks, the parts of the brain involved with pain perception became active while they waited. For the participants who preferred to wait, those parts of the brain weren't active until the actual shock. In other words, for "extreme dreaders", waiting for punishment is as bad as the punishment itself, and chosing the larger immediate shock is a rational decision.

I got my arm twisted to be a participant in a study involving shocks a while back, and while the cash payment at the end was appreciated, the shock really does hurt! And the dread, as you know the shock is coming, makes you nervous, which makes you sweat, which makes your skin conductivity go up, which makes the shock even worse.



Post a Comment

Subscribe to Post Comments [Atom]

<< Home