Damn. 

When it comes to making decisions, our brains are extremely dependent on past experiences. In fact, some cognitive scientists speculate that the brain has a built-in mechanism for assessing (or weighing) the efficacy of a decision based on precedents from the past. It's also something we can be conscious of; to improve our rational decision making, it's important that we use new information to change our confidence in a belief. But as a recent experiment conducted by Alla Karpova of the Janelia Farm Research Campus shows, randomness may be the brain's preferred policy when things get particularly challenging or when the situation is completely without precedent.