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Sleep and memory studies often focus on overnight rather than long‐term memory changes, traditionally associating overnight memory change (OMC) with sleep architecture and sleep patterns such as spindles. In addition, (para‐)sympathetic innervation has been associated with OMC after a daytime nap using heart rate variability (HRV). In this study we investigated overnight and long‐term performance changes for procedural memory and evaluated associations with sleep architecture, spindle activity (SpA) and HRV measures (R‐R interval [RRI], standard deviation of R‐R intervals [SDNN], as well as spectral power for low [LF] and high frequencies [HF]). All participants (N = 20, Mage = 23.40 ± 2.78 years) were trained on a mirror‐tracing task and completed a control (normal vision) and learning (mirrored vision) condition. Performance was evaluated after training (R1), after a full‐night sleep (R2) and 7 days thereafter (R3). Overnight changes (R2‐R1) indicated significantly higher accuracy after sleep, whereas a significant long‐term (R3‐R2) improvement was only observed for tracing speed. Sleep architecture measures were not associated with OMC after correcting for multiple comparisons. However, individual SpA change from the control to the learning night indicated that only "SpA enhancers" exhibited overnight improvements for accuracy and long‐term improvements for speed. HRV analyses revealed that lower SDNN and LF power was associated with better OMC for the procedural speed measure. Altogether, this study indicates that overnight improvement for procedural memory is specific for spindle enhancers, and is associated with HRV during sleep following procedural learning. [ABSTRACT FROM AUTHOR]

Summary Differences in sleep and awakening quality between 51 insomniac postmenopausal syndrome patients and normal controls were evaluated. In a subsequent double-blind, placebo-controlled, comparative, randomized, three-arm trial (Climodien 2/3 = estradiol valerate 2 mg + the progestogen dienogest 3 mg = regimen A, estradiol valerate 2 mg = regimen EV, and placebo = regimen P), the effects of 2 months of hormone replacement therapy were investigated, followed by a 2-month open-label phase in which all patients received Climodien[sup ®] 2/2 (EV 2 mg + dienogest 2 mg = regimen A*). Polysomnography at baseline demonstrated significantly deteriorated sleep initiation and maintenance, increased S1 and decreased S2 in patients. Subjective sleep and awakening quality, well-being, morning drive, wakefulness, memory and reaction time performance were deteriorated too. Treatment with both regimen A and regimen EV induced a moderate, although nonsignificant, improvement in the primary efficacy variable wakefulness during the total sleep period compared with baseline, while under placebo no changes occurred. Secondary efficacy variables concerning sleep initiation and maintenance, and sleep architecture showed similar findings. The apnea and apnea–hypopnea indices improved significantly under regimen A, compared with both baseline and placebo. Subjective sleep and awakening quality improved significantly after regimen A and EV compared with baseline, with the drug-induced changes being superior to those induced by placebo. In the open-label phase, subjective sleep quality improved further, significantly in the former regimen A group. Awakening quality, somatic complaints and morning thymopsyche did not yield any significant findings. Concerning morning noopsychic performance, memory improved significantly after regimen A compared with baseline, fine motor activity after regimen EV. Reaction time performance increased with all three compounds. In conclusion, Climodien significantly improved subjective sleep quality, the apnea and apnea–hypopnea indices of insomniac postmenopausal syndrome patients, while it only marginally improved variables concerning objective sleep and awakening quality. [ABSTRACT FROM AUTHOR]