Sophisticated sleep improves our brains: Our advanced cognitive and social skills might derive from the evolution of improved sleep quality; today, sleep therapy could help with mental health issues and learning.

Abstract

In the past decades, sleep researchers have been quietly accumulating knowledge about the physiology of sleep. Without any real health application for this knowledge, however, the public and the press have slept blissfully through most of their breakthroughs. Yet, recent findings about the evolution of sleep in humans and the effects of sleep disruption on human health seem to have finally woken the public up. A recent paper from David Samson and Charles Nunn, evolutionary anthropologists from Duke University in the USA, puts forward the hypothesis that humans have evolved more efficient sleep patterns than other primates and that this is because “[e]arly humans experienced selective pressure to fulfill sleep needs in the shortest time possible” [1]. This efficient slumber, the authors argue, might have contributed to setting our ancestors on the evolutionary path toward human civilization. The New York Times , among other newspapers, covered the publication, which follows in the wake of research indicating that human sleep patterns have stayed largely stable during the course of human evolution, from hunter‐gatherers to modern city dwellers [2]. Both of these insights provide evolutionary context for the health impact of too little sleep, with both epidemiological and clinical research showing that sleep disruption has a negative effect on health and well‐being. More recently, however, there is evidence that sleep has distinctly positive therapeutic potential to treat a variety of phobias and other psychotic conditions. The evolutionary study that attracted media attention raises interesting questions about the co‐evolution of sleep and human cognitive faculties. Samson and Nunn suggest that sleep became subject to strong selective pressures—“including increased predation risk […] threats from intergroup conflict, and benefits arising from increased social interaction” [1]—when our ancestors moved down from the trees and onto the savannah. As a result, …