In Audrey Niffenegger’s novel “The Time Traveler’s Wife,” Henry DeTamble is a man with a rare disorder that causes him to involuntarily travel through time. His wife Clare experiences life linearly, but never knows when or where she will see her husband next. “Each moment that I wait feels like a year,” Clare says. “Through each moment I can see infinite moments lined up, waiting.” You don’t need a time-traveling husband to have a warped experience of time like Clare’s—think of how long a Monday back at work seems to stretch out, and how quickly the weekend flashes by. Time should march steadily, but that doesn’t always match our perception. Neuroscientists and psychologists are searching for answers to this conundrum, using psychophysical experiments and brain scanning technology to unlock just how human brains track the passage of time. Researchers are gaining insights, and some of these findings could help us to better understand, among other things, disorders like schizophrenia and Parkinson’s where sufferers have trouble perceiving time.