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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]

Interrater variability of sleep stage scorings has an essential impact not only on the reading of polysomnographic sleep studies (PSGs) for clinical trials but also on the evaluation of patients’ sleep. With the introduction of a new standard for sleep stage scorings (AASM standard) there is a need for studies on interrater reliability (IRR). The SIESTA database resulting from an EU-funded project provides a large number of studies ( n = 72; 56 healthy controls and 16 subjects with different sleep disorders, mean age ± SD: 57.7 ± 18.7, 34 females) for which scorings according to both standards (AASM and R&K) were done. Differences in IRR were analysed at two levels: (1) based on quantitative sleep parameter by means of intraclass correlations; and (2) based on an epoch-by-epoch comparison by means of Cohen’s kappa and Fleiss’ kappa. The overall agreement was for the AASM standard 82.0% (Cohen’s kappa = 0.76) and for the R&K standard 80.6% (Cohen’s kappa = 0.68). Agreements increased from R&K to AASM for all sleep stages, except N2. The results of this study underline that the modification of the scoring rules improve IRR as a result of the integration of occipital, central and frontal leads on the one hand, but decline IRR on the other hand specifically for N2, due to the new rule that cortical arousals with or without concurrent increase in submental electromyogram are critical events for the end of N2. [ABSTRACT FROM AUTHOR]

Summary: 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. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented commenting on the case report of the 68-year-old man suffering from jumping stump syndrome in a lower limb with a history of arterial hypertension and peripheral arterial occlusive disease.

The precise etiology of the restless legs syndrome (RLS) is unknown. Sensory and motor symptoms of RLS worsen during evening/night, coincident with the physiological peak of pineal melatonin excretion. Decreased melatonin levels have been reported in insomnia, which is an associated feature of RLS. Melatonin substitution improved insomnia. A potential association between the idiopathic RLS (iRLS) and alterations in melatonin excretion was therefore explored. Daytime (7:00–22:00 hr) and night-time (22:00–7:00 hr) urinary excretion of 6-OH-melatonin-sulfate (aMLTs) was measured in 15 patients with iRLS and 11 controls by a radioimmunoassay. There was no significant difference between daytime and night-time urinary aMLTs excretion in iRLS as compared with controls (daytime: 6.14 ± 5.20 ng versus 5.02 ± 5.11 ng, NS; night-time: 21.07 ± 17.05 ng versus 22.92 ± 16.52 ng, NS). Our data do not provide evidence for a decrease of cumulative melatonin production in iRLS. Insomnia in RLS does not seem to be correlated with a deficit of melatonin. [ABSTRACT FROM AUTHOR]

Describes the progesterone treatment of a woman with a most likely congenital myopathy and shows that interdisciplinary cooperation can be productive. Symptoms presented by the patient; Medical history; Overview of myopathy; Progesterone dosage.

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., (Copyright © 2012 Wiley Periodicals, Inc.)

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.)