A data-driven measure of REM sleep propensity for human and rodent sleep

IntroductionMammalian sleep is characterized by alternations between episodes of rapid-eye-movement sleep (REMS) and non-REM sleep (NREMS). The phenomenon of REMS pressure, namely a drive for REMS that builds up between REMS episodes, is thought to govern the timing of these ultradian NREMS-REMS cycles. Prior analyses of NREMS-REMS cycles in mice suggested that time in NREMS is a primary contributor to REMS pressure. We previously introduced a REMS propensity measure defined as the probability t