Tsukuba, Japan—During deep sleep, brain wave amplitude increases, and "δ (delta) power," a key objective indicator of sleep quality, is observed; higher delta power corresponds to deeper, more ...

We’re all time-poor, so multi-tasking is seen as a necessity of modern living. We answer work emails while watching TV, make shopping lists in meetings and listen to podcasts when doing the dishes. We ...

Multitasking usually lowers productivity because most people are “task switching,” which creates a mental “switch cost” that slows processing and reduces accuracy. Switching between tasks strains ...