Sleep and moral awareness.

The implications of sleep for morality are only starting to be explored. Extending the ethics literature, we contend that because bringing morality to conscious attention requires effort, a lack of sleep leads to low moral awareness. We test this prediction with three studies. A laboratory study with a manipulation of sleep across 90 participants judging a scenario for moral content indicates that a lack of sleep leads to low moral awareness. An archival study of Google Trends data across 6 years highlights a national dip in Web searches for moral topics (but not other topics) on the Monday after the Spring time change, which tends to deprive people of sleep. Finally, a diary study of 127 participants indicates that (within participants) nights with a lack of sleep are associated with low moral awareness the next day. Together, these three studies suggest that a lack of sleep leaves people less morally aware, with important implications for the recognition of morality in others.