#78: Napping Neurons Explain Sleep-Deprived Blunders


When tiredness sets in, poor decisions and clumsiness often follow. In a study published last April, scientists may have pinpointed the biological basis of such mistakes: tiny clusters of neurons that start napping, even as the brain stays awake. To explore the phenomenon, neuroscientist Giulio Tononi of the University of Wisconsin at Madison tempted lab rats to stay awake longer than usual by supplying them with a steady stream of new toys. At the same time, he measured their brain activity through electroencephalography (EEG). With so much exploring to do, the rats seemed alert, but measurements told a different story. Though EEG recordings indicated overall wakefulness, small groups of neurons briefly went offline. Bits of the brain seemed to be power napping—and as the rat stayed awake longer, the frequency of the naps increased. Most of the time these localized naps did not affect a rat’s behavior, but some led to errors. Similar lapses in humans may cause us to make bad decisions or forget what we are saying, a possibility the team is now investigating.