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Insomnia is a sleeping disorder, usually studied from a behavioural perspective, with a focus on somatic and cognitive arousal. Recent studies have suggested that an impairment of information processes due to the presence of cortical hyperarousal might interfere with normal sleep onset and/or consolidation. As such, a treatment modality focussing on CNS arousal, and thus influencing information processing, might be of interest. Seventien insomnia patients were randomly assigned to either a tele-neurofeedback (n = 9) or an electromyography tele-biofeedback (n = 8) protocol. Twelve healthy controls were used to compare baseline sleep measures. A polysomnography was performed pre and post treatment. Total Sleep Time (TST), was considered as our primary outcome variable. Sleep latency decreased pre to post treatment in both groups, but a significant improvement in TST was found only after the neurofeedback (NFB) protocol. Furthermore, sleep logs at home showed an overall improvement only in the neurofeedback group, whereas the sleep logs in the lab remained the same pre to post training. Only NFB training resulted in an increase in TST. The mixed results concerning perception of sleep might be related to methodological issues, such as the different locations of the training and sleep measurements.

The effect of partial sleep deprivation (PSD) on driving abilities, as measured with a driving simulator, and the value of slow‐release caffeine as a countermeasure to the expected performance decrements, were studied. Twelve subjects, between 20 and 25 years of age, underwent four experimental conditions, 4.5 or 7.5 h time in bed (TIB) with 300 mg slow‐release caffeine or placebo, according to a Latin square design. Driving performance was measured twice by a 45‐min driving task on a simulator. Subjective sleepiness/alertness and mood were assessed four times, by means of the Stanford Sleepiness Scale (SSS) and Profile of Mood States (POMS). After 4.5 h as compared with 7.5 h TIB lane drifting and speed deviation were higher, but only the effect on the first variable reached significance. In the placebo condition at 13.00 h, accident liability increased after PSD. Subjective sleepiness was higher in the 4.5 h TIB group. Caffeine intake gave rise to a decrease in lane drifting and after PSD it led to a smaller speed deviation and accident liability. The findings suggest that a lack of sleep can lead to a significant driving performance impairment, with drivers having problems to maintain an appropriate road position and a posted speed and more drivers getting involved in an accident. Secondly, the results indicate that caffeine – more specifically slow‐release caffeine – can serve as a valuable countermeasure to these performance decrements, in the absence of any important side‐effects, especially when its application is of an acute nature and when there is no opportunity to take a nap.

This study combines concepts of bed design and sleep registrations to investigate how quality of spine support affects the manifestation of sleep in healthy subjects. Altogether, 17 normal sleepers (nine males, eight females; age 24.3±7.1 years) participated in an anthropometric screening, prior to the actual sleep experiments, during which personalised sleep system settings were determined according to individual body measures. Sleep systems (i.e. mattress and supporting structure) with an adjustable stiffness distribution were used. Subjects spent three nights of 8 h in bed in the sleep laboratory in a counterbalanced order (adaptation, personalised support and sagging support). During these nights, polysomnography was performed. Subjective sleep data were gathered by means of questionnaires. Results show that individual posture preferences are a determinant factor in the extent that subjects experience a negative effect while sleeping on a sagging sleep system. STATEMENT OF RELEVANCE: This study investigated how spine support affects sleep in healthy subjects, finding that the relationship between bedding and sleep quality is affected by individual anthropometry and sleep posture. In particular, results indicate that a sagging sleep system negatively affects sleep quality for people sleeping in a prone or lateral posture.