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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]

Objectives: The Pupillographic Sleepiness Test (PST) measures the level of alertness based on spontaneous oscillations in pupillary size. Reference data are available for male and female adults within the age range 20-60 years. The aim of the present multicenter study was to extend the age range for reference data from 20 to 79 years. Methods: A total of 239 healthy subjects, selected from three different centers (Berlin, Regensburg, and Vienna), were administered the PST. Data were analyzed with respect to possible effects of age, gender, and time of day on the pupillary unrest index (PUI) and the pupil diameter (PD). Results: Reliable data were available in 85.8% of the entire study sample and in 82.4% of elderly subjects (60+ years). Age-related changes were identified for the PUI and PD. There was no effect of gender on pupillometric variables as revealed by univariate analysis. The PD was found to be smaller in the afternoon compared with the morning. However, if subjects aged 60+ years were excluded from the analyses, the age-related changes disappeared and a time-of-day effect regarding the PUI became apparent. Conclusions: PUI and PD were found to decrease with increasing age. In addition, the present data show that nonreliable PST data occur more frequently in the elderly probably because of dry eyes, inadequate testing conditions, and technical resolution limitations. Thus, the PST results obtained here from elderly subjects are limited and have to be interpreted with caution. Additional research on elderly specific assessment tools is needed. Am. J. Hum. Biol. 2012. © 2012Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the role of EEG mapping as an objective and quantitative measure of vigilance in untreated and modafinil-treated narcoleptics, and compare it with the conventional neurophysiological method of the Multiple Sleep Latency Test (MSLT) and the subjective Epworth Sleepiness Scale (ESS). In 16 drug-free narcoleptics and 16 normal controls a baseline 3-min vigilance-controlled EEG (V-EEG) and a 4-min resting EEG (R-EEG) were recorded during midmorning hours. Thereafter, in a double-blind, placebo-controlled crossover design, patients were treated with a 3-week fixed titration of modafinil (200, 300, 400 mg) and placebo. EEG-mapping, MSLT and ESS measures were obtained before and at the end of the third week of therapy. Statistical overall analysis by means of the omnibus significance test demonstrated significant EEG differences between untreated patients and controls in the resting condition only (R-EEG). Subsequent univariate analysis revealed an increase in absolute and relative theta power, a decrease in alpha-2 and beta power as well as a slowing of the dominant frequency and the centroids of the alpha, beta and total power spectrum and thus objectified a vigilance decrement in narcolepsy. Modafinil 400 mg/d significantly improved vigilance as compared with placebo (p = 0.01), inducing changes opposite to the aforementioned baseline differences (key-lock principle). The MSLT and the ESS also improved under modafinil as compared with placebo, but changes were less consistent. Spearman rank correlations revealed the highest correlations between EEG mapping and the ESS, followed by those between EEG mapping and the MSLT, while the lowest correlation was found between the MSLT and the ESS. In conclusion, EEG mapping is a valuable instrument for measuring vigilance decrements in narcolepsy and their improvement under psychostimulant treatment. [ABSTRACT FROM AUTHOR]

Objectives Along with spindles, K-complexes are well known hallmarks of stage 2 (S2) sleep. However, little is known about their quantity in S2 sleep of patients with Parkinson's disease (PD). Setting Sleep laboratory, Department of Neurology, University of Vienna, Austria. Patients and methods Whole-night polysomnography (PSG) was performed in twelve treated PD patients and ten healthy controls without history of sleep complaints. The quantity of spontaneous K-complexes, K-alpha-complexes, and sleep spindles in one hour S2 sleep, distributed in four epochs of 15 minutes all through the night, were visually selected and analysed. The quantity and the temporal course of these phasic events were compared with the quantity in age-matched healthy controls. Nine of the twelve PD patients underwent [123I]Β-CIT SPECT for calculating dopamine transporter binding in the striatum and serotonin transporter density in the thalamus-hypothalamus region. Results There was no difference between the quantity of K-complexes, K-alpha-complexes, and sleep spindles in PD patients and in the healthy control group. K-complexes but not sleep spindles decreased over the night in both groups. The number of sleep spindles did not correlate with the dopamine transporter binding in the striatum or the serotonin binding in the thalamic/hypothalamic region. Conclusion K-complexes and sleep spindles are not reduced and do not seem to be related to the degree of dopaminergic degeneration in treated PD patients. [ABSTRACT FROM AUTHOR]

Background: The objective of this study was to assess the influence of nocturnal headaches (NH) on subjective sleep parameters prospectively in habitual snorers and their bed partners.Methods: We recruited habitual snorers and their bed partners via newspaper articles. The participants completed a semistructured interview, filled in questionnaires about quality of sleep (PSQI), daytime sleepiness (ESS), depression (SDS) and anxiety (SAS) and they kept a 90-day headache and sleep diary.Results: Seventy-six snorers (25 female) and 41 bed partners (31 female) completed the study recording a total of 6690 and 3497 diary days, respectively. NH were recorded on 222 (3.3%) and 79 (2.2%) days in 32 (42%) snorers and 17 (41%) bed partners, respectively. Snorers with NH showed significantly higher PSQI (5 ± 3 vs. 4 ± 2, p = 0.004), SAS (38 ± 11 vs. 31 ± 10, p = 0.011) and SDS scores (39 ± 12 vs. 34 ± 10, p = 0.048) than snorers without NH. For bed partners with NH we found a significant female predominance (sex ratio f:m = 16:1 vs. 12:12, p = 0.005) and significantly higher SAS scores (38 ± 6 vs. 33 ± 8, p = 0.030) compared with bed partners without NH. The subjective quality of sleep in habitual snorers (p < 0.001) as well as their bed partners (p = 0.017) was negatively influenced by NH, but not total sleep time.Discussion: NH occurred in around 40% of snorers and their bed partners at least once during the 90-day observation period. Our results confirmed a negative impact on the subjective quality of sleep in both groups. [ABSTRACT FROM AUTHOR]

Many studies investigating sleep and memory consolidation have evaluated full-night sleep rather than alternative sleep periods such as daytime naps. This multi-centre study followed up on, and was compared with, an earlier full-night study (Schabus et al., 2004) investigating the relevance of daytime naps for the consolidation of declarative and procedural memory. Seventy-six participants were randomly assigned to a nap or wake group, and performed a declarative word-pair association or procedural mirror-tracing task. Performance changes from before to after a 90-min retention interval filled with sleep or quiet wakefulness were evaluated between groups. Associations between performance changes, sleep architecture, spindles, and slow oscillations were investigated. For the declarative task we observed a trend towards stronger forgetting across a wake period compared with a nap period, and a trend towards memory increase over the full-night. For the procedural task, accuracy was significantly decreased following daytime wakefulness, showed a trend to increase with a daytime nap, and significantly increased across full-night sleep. For the nap protocol, neither sleep stages, spindles, nor slow oscillations predicted performance changes. A direct comparison of day and nighttime sleep revealed that daytime naps are characterized by significantly lower spindle density, but higher spindle activity and amplitude compared with full-night sleep. In summary, data indicate that daytime naps protect procedural memories from deterioration, whereas full-night sleep improves performance. Given behavioural and physiological differences between day and nighttime sleep, future studies should try to characterize potential differential effects of full-night and daytime sleep with regard to sleep-dependent memory consolidation., (© 2017 The Authors. Journal of Sleep Research published by John Wiley & Sons Ltd on behalf of European Sleep Research Society.)

Objectives: To acquire current information on sleep habits, disturbances and treatment options in the adult population of Austria and compare results with previously collected data., Materials and Methods: A representative sample of the Austrian population (women: n = 522, men: n = 478)., Results: Seventy-five percent reported daily sleep-duration between 6 and 8 h. In 76%, sleep latency was <30 min, 15% described difficulties in sleep maintenance. Longer sleep on weekends was prevalent in 54%, 23% took a nap. Concerning sleep environment, 31% reported sleeping alone; the rest had a constant or occasional bed partner. Sleep disturbances such as sleep disruption or prolonged sleep latency were reported by 18%. Predominant symptoms included snoring/apneas (22%), nightmares (22%) and restless legs (21%). Daytime tiredness was reported by 17% and sleepiness by 20%. Twenty-four percent did not take treatment. Only 7% asked for medical help: 96% consulted their physician; 47% tried to change their way of living. Sleep promoting drugs were taken by 7%. Sleep improving measures were: sleep promoters (45%), general measures (20%), consultation of general practitioner (20%), psychotherapy (6%), and technical tools (3%). Comparison with a dataset of 1993 revealed only a slight increase in short sleepers and a slight decrease in long sleepers., Conclusions: Subjectively reported sleep disorders proved to be relatively stable between 1993 and 2007., (Copyright © 2010 The Authors. Journal compilation © 2010 Blackwell Munksgaard.)