Methodological approach to sleep state misperception in insomnia disorder: Comparison between multiple nights of actigraphy recordings and a single night of polysomnography recording.

Study Objective: To provide a comprehensive assessment of sleep state misperception in insomnia disorder (INS) and good sleepers (GS) by comparing recordings performed for one night in-lab (PSG and night review) and during several nights at-home (actigraphy and sleep diaries).

Methods: Fifty-seven INS and 29 GS wore an actigraphy device and filled a sleep diary for two weeks at-home. They subsequently completed a PSG recording and filled a night review in-lab.

Effects of cognitive behavioral therapy for insomnia on subjective and objective measures of sleep and cognition.

Study Objectives: To assess the effects of Cognitive Behavioral Therapy for insomnia (CBTi) on subjective and objective measures of sleep, sleep-state misperception and cognitive performance.

Methods: We performed a randomized-controlled trial with a treatment group and a wait-list control group to assess changes in insomnia symptoms after CBTi (8 weekly group sessions/3 months) in 62 participants with chronic insomnia. To this end, we conducted a multimodal investigation of sleep and cognition including subjective measures of sleep difficulties (Insomnia Severity Index [ISI]; sleep diaries) and cognitive functioning (Sahlgrenska Academy Self-reported Cognitive Impairment Questionnaire), objective assessments of sleep (polysomnography recording), cognition (attention and working memory tasks), and sleep-state misperception measures, collected at baseline and at 3-months post-randomization.