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Monkeys and Cognitive Dissonance
Hugh Pickens writes "People deal with cognitive dissonance — the clashing of conflicting thoughts — by eliminating one of the thoughts. Psychologists have suggested we hone our skills of rationalization in order to impress others, reaffirm our "moral integrity" and protect our "self-concept" and feeling of "global self-worth." Now experimenters at Yale have demonstrated that other primates employ the same psychological mechanism. In one experiment, a monkey was observed to show an equal preference for three colors of M&M's and was given a choice between two of them. If he chose red over blue, his preference changed and he downgraded blue. When he was subsequently given a choice between blue and green, it was no longer an even contest — he was now much more likely to reject the blue. Rationalization is thought to have an evolutionary utility; once a decision has been made, second-guessing may just interfere with more important business. "We tend to think people have an explicit agenda to rewrite history to make themselves look right, but that's an outsider's perspective. This experiment shows that there isn't always much conscious thought going on," said one researcher."
Very good point. I actually did some Googling to check this out and I found this abstract http://jp.physoc.org/cgi/content/abstract/528/3/573. What I got out of this is that apparently the genus of monkeys they used (Cebus, which are "New world" monkeys) are known to be highly varied in trichromacy (most females) vs dichromacy (all males(?)) among sexes. So I guess the easiest way for them to not have to worry about that is by using all male monkeys... but then again, as someone with a very incomplete knowledge of vision physiology and neuroprocessing, I'm not sure how those dichromatic monkeys would perceive the third color.
The only consistency in life is the lack thereof
I haven't worked in the vision lab for a few months (and I did only work with humans), so maybe I'm getting rusty :) but I thought that it would be easy for even a dichromat to distinguish between red and blue? I mean, what single cone, if disabled, would produce a difficulty in distinguishing red from blue?
Did you mean maybe that these monkeys diverged from humans' evolutionary branch before the red and green cones differentiated from the older, yellow cone? If that were the case, they still should have no trouble distinguishing red from blue.
Mods - if you must agree with the parent, rank it "Funny" or at least "Insightful"... but there is nothing informative about it.
Everything is easy when you don't understand the problem.
Not that I am in any way supporting or rejecting the claims made in the study, but your criticism is probably unfounded**.
.05), and designated the items within each triad as choices A, B, and C (choices were specific to each individual monkey); although there were no significant differences in preferences across the three M&M colors within a triad, we conservatively used each subject's least preferred color of the three (i.e., the one the monkey took longest to obtain during preference testing) as option C.
The M&M (and sticker choices) were different across subjects, so it is unlikely that a systematic bias could result from visual perception of the items. The M&M choices chosen for the subjects were determined by relatively equal preference in a pretraining phase of the experiment. Given the fact that they find an effect, it's unlikely that it's due to an inability to tell the items apart.
Specifically:
We first assessed the monkeys' existing preferences for M&M's of different colors by timing how long they took to retrieve individual M&M's. For each monkey, preferences for at least nine different M&M colors were assessed. As each preference test began, the monkey was inside its home cage, just outside a testing chamber, and was allowed to watch as the experimenter placed one colored M&M on a tray outside the other side of the chamber. The door to the testing chamber was opened, and the monkey was allowed to enter when it wished to retrieve the M&M. We measured how quickly the monkey entered the testing chamber to retrieve the M&M. Preferences for each color were assessed across 20 trials per monkey; trials for each color spanned two experimental sessions.
After preference testing, we performed analyses of variance to determine whether each monkey had statistically significant preferences. We identified triads of equally preferred colors (all ps >
**By the way, I've been reading your slashdot comments for quite some time, and so don't take this as a personal affront or anything. =) I think you're probably one of the better scientist/posters on the site. =)
They also don't seem to have taken into account some monkeys drop all thought as a method of resolution. Obviously better equipped for survival.
BM3
The monkeys had experience eating all of the colors of M&Ms used in the experiment (and, there were more colors than the few you mention). Safety of the choice has little to do with the outcome.
Wow, mod parent down. The article gave ONE example (Red-Blue-Green), but as was mentioned elsewhere, the original study had a variety of colors, and different monkeys chose different initial preferences. It was a science article in the New York Times, which glossed over some facts. See the original study to understand why the parent's "blue hypothesis" should not be considered a factor.
That's the GPs point. You wouldn't stop and decide. If you know they are both equally as good, then the first time you would take either path, doesn't matter which one.
The second time, you would take the one you took last time (saves you having to stop and think about it) because you survived by going down that one last time. Re-enforcement.
America, Home of the Brave.
They taste exactly the same.
Tell that to van halen
I'll eat all the colors of M&M's. I just like eating the ones of related or single color at the same time (e.g not mixing green and red, but red and yellow together are OK, or green and blue together are OK. Brown and red are acceptable, but it's best to eat brown alone.) Completely irrational, I know, but harmless.
...the future crusty old bastards are already drinking the Kool-Aid.