Ever walk into a room with some purpose in mind, only to completely forget what that purpose was? Turns out, doors themselves are to blame for these strange memory lapses. Psychologists at the University of Notre Dame have discovered that passing through a doorway triggers what’s known as an event boundary in the mind, separating one set of thoughts and memories from the next. Your brain files away the thoughts you had in the previous room and prepares a blank slate for the new locale.
If you can’t concentrate during the irritating sound of a truck reversing, blame the brain baffle on an evolutionary glitch. Natural sounds are created from a transfer of energy (say, a stick hitting a drum) and gradually dissipate, and our perceptual system has evolved to use that decay of sound to figure out what made it and where it came from. But beeps don’t typically change or fade away over time, so our brains have trouble keeping up.
Other sounds that may leave you baffled are the noises your cat makes.
We walk in circles when we traverse terrain devoid of landmarks, such as the desert. Even though we’d swear we’re walking in a straight line, we actually curve around in loops as tight as 20 metres in diameter. German research from the Max Planck Institute for Biological Cybernetics reveals why: with every step a walker takes, a small deviation arises in the brain’s balance (vestibular) or body awareness (proprioceptive) systems. These deviations accumulate to send that individual veering around in ever-tighter circles. But they don’t occur when we can recalibrate our sense of direction, using a nearby building or mountain, for instance.