We think of brains as computers—stimulus in, action out. But they’re far more finicky than any iMac. Easily swayed by underlying internal states such as hunger, aggression, or arousal, our neurons are capable of incredible flexibility. For neuroscientists, it’s yet another wrinkle in understanding our wrinkliest organ.
Life is full of binary choices, even for small animals like fruit flies. With new technologies, scientists can now dissect the mechanisms of decision making in the simplest of brains, at the levels of individual molecules, cells, and networks.