REM sleep deprivation suppresses acquisition of classical eyeblink conditioning.

STUDY OBJECTIVES The aim of this study was to investigate the issue of whether REM sleep is involved in implicit learning through the cerebellum-related neural circuit via the use of classical eyeblink conditioning (CEC). DESIGN Subjects were divided into three groups: control (sleep without interruption), REM sleep deprivation (RD), and slow wave sleep (stage 3+4) deprivation (SD). The CEC was performed after 8 hours of ordinary nocturnal sleep or sleep disrupted at a selected sleep stage. SETTING A university-based sleep laboratory. PATIENTS OR PARTICIPANTS Twenty-seven healthy volunteers (all men, aged 23.2+/-0.6 years). INTERVENTIONS The CEC was measured after selective sleep deprivation or ordinary nocturnal sleep. MEASUREMENTS AND RESULTS The eyeblink reflex was conditioned using a classical delay conditioning paradigm. The conditioned response (CR) was determined by electromyography measurements of the orbicularis oculi muscles. The rate of appearance of the CR was compared among the three groups. Compared with the control subjects, RD subjects were significantly deficient in their capacity to acquire conditioned eyeblinks, while no difference was found among the SD subjects. CONCLUSIONS This study suggests that RD suppresses the cerebellar function in CEC and that REM sleep is closely linked with the learning function in the cerebellum.