Say you live across from a bakery. Sometimes you are hungry, and therefore tempted when odors waft through your window, but other times satiety makes you indifferent. Sometimes popping over for a popover seems trouble-free, but sometimes your spiteful ex is there. Your brain balances many influences in determining what you’ll do. A new MIT study details an example of this working in a much simpler animal, highlighting a potentially fundamental principle of how nervous systems integrate multiple factors to guide food-seeking behavior. All animals share the challenge of weighing…