the white elephant of emotion and rationality

"the Platonic metaphor of the mind as a charioteer driving twin horses of reason and emotion is on the right track - except that cognition is a smart pony, and emotion a big elephant".

the new zeland news reports on neuroscientific studies trying to explain why humans, despite what economists say, behave irrationally sometimes (or, more than sometimes, as i've observed). the article states that economics is based on the fallacy that people behave rationally when making economic decisions. economists and behavioral scientists have been bickering about this for a while, but neuroscience may have something interesting to say about it.

first let me say in defense of economics: saying that economics is based on individual rational behavior is untrue - from my admittedly limited study of the subject it seems it's really the study of aggregate behavior, which does usually tend towards the rational laws economists espouse. individual behaviors are a different story. it's true that we all make decisions based on what we see as the costs and benefits of the outcome, but how accurately we can gauge that outcome in objective standards is another question entirely and should be the subject of it’s own post.

the nz reports on the classic study where person a gets $10 and has the option of giving some to person b. person b can accept or reject the gift. typically if person a offers only a dollar or two, person b rejects the gift, presumably because s/he’s offended. however that’s not usually how it happens – person a typically offers nearly half of what s/he’s given, and person b usually accepts it.

in the experiment, both person a and b have a clear understanding that what position they’re in is a result wholly of the turn of the die. that “a” has $10 and “b” none has nothing to do with hard work, only randomization on the part of the experimenter. i wonder how the results would change if there were a pre-game that distributed the money more meritocratically. or if person b was told that the $10 came straight out of person a’s pocket, and not the lab’s. this would give us a clearer picture of how these situations work in the “real world.”

i’d argue that perhaps taking that one dollar as opposed to rejecting the offer is not always the most rational choice anyway. there are things that people value more than one dollar, including pride. perhaps person “b” is in reality paying one dollar for the ability to hurt person “a”’s feelings like a did to him/her.

now about the neuroscience: when person b is offered only a few bucks, the insular cortex "lights up." ignoring my extreme skepticism about MRIs, this is not surprising. we think the insular cortex has to do with happiness/sadness (and a bunch of other things like memory and language). according to this study, the prefrontal “competes” with the insular cortex, and is the source of the rational impulse to take the low offer. the more “activated” the insular, the more likely to reject the offer, and the more “activated” the prefrontal, the more likely to accept.

does this mean that the insular cortex is related to emotional (and therefore objectively unwise) reactions and the prefrontal to more rational deliberation? maybe. it’s true the prefrontal cortex is thought to be involved in coordinating thoughts and actions in a goal-directed way. it’s also, interestingly enough, thought to be involved in impulse control and “forward thinking.” perhaps it’s the mature part of the brain.

more on this later i'm sure. it's a constant theme of economics and behavioral science.

Labels: decision making, neuroscience, well being