We may be biologically programmed to like what we buy

You surely know that people who buy a product become fans of that product. (Usually, unless that product really stinks.) We end up with the Mac vs. PC argument, Coke vs. Pepsi, even our political polarization.

It turns out that not only do normal people do this, but even people with amnesia who can't remember choosing. Psychologists had students and amnesia patients choose between two different posters, and both groups had stronger preferences later after making a choice. Even if they couldn't remember the first choice at all.

Not only that, but they see the same behaviour in monkeys. After choosing between different colored M&Ms, monkeys start to prefer the color they chose and dislike the color they previously rejected.

I'm not sure what this all means, but clearly my increased excitement about science will persist even after I don't remember this particular study.