Sleep deprivation produces feelings of vicarious agency.

A variety of self-related psychological constructs are supported by the fundamental ability to accurately sense either self-agency or lack of agency in some action or outcome. Agency judgments are typically studied in individuals who are well-rested and mentally-fresh; however, in our increasingly fast-paced world, such judgments often need to be made while in less optimal states. Here, we studied the effect of being in one such non-optimal state - when sleep-deprived - on judgments of agency. We found that 24h of total sleep deprivation elevated agency ratings on trials designed to produce a strong sense of non-agency. These data provide the first evidence that physiological state variables can affect agency processing in the normal population.