Pre-sleep cognitive activity in adults: A systematic review.

This systematic review focuses on three themes: 1) the nature of pre-sleep cognitive activity in good sleepers and individuals with insomnia, 2) the links between measures of pre-sleep cognitive activity and sleep onset latency (SOL) or insomnia, and 3) the effect of manipulating pre-sleep cognitive activity on SOL or insomnia. Regarding the first theme, mentation reports have been collected in a sleep laboratory, with an ambulatory monitoring device, or using a voice-activated tape-recorder. Normal transition to sleep is characterized by sensorial imagery, deactivation of higher cognitive processes, and hallucinations. Moreover, pre-sleep thoughts in individuals with insomnia frequently relate to planning or problem-solving, and are more unpleasant than in good sleepers. Regarding the second theme, twelve questionnaires and three interviews were identified. Insomnia is associated with more thoughts interfering with sleep, counterfactual processing, worries, maladaptive thought control strategies, covert monitoring, and cognitive arousal. Regarding the third theme, several strategies have been tested: mental imagery, hypnosis, paradoxical intention, articulatory suppression, ordinary suppression, and distraction. Their effect is either beneficial, negligible, or detrimental. Future research should focus on the mechanisms through which some forms of cognitive activity affect sleep onset latency.

Brief school-based interventions to assist adolescents' sleep-onset latency: Comparing mindfulness and constructive worry versus controls.

Difficulties falling asleep are common among adolescents, especially during times of stress. Adolescents may thus benefit from brief techniques (15 min) that decrease pre-sleep cognitive-emotional arousal and sleep-onset latency. The present study used a 3 (intervention: mindfulness bodyscan mp3, constructive worry, control) by 3 (time: baseline, week 1, week 2) mixed-model design on a school-based sample of adolescents (N = 232; Mage  = 15.9 ± 0.8 years, range = 14-18 years; 19% male), and a sub-sample of adolescents with prolonged sleep-onset latency (i.e. ≥30 min; N = 119; Mage  = 16.9 ± 0.9 years; 21% male). It was expected that the 15-min pre-recorded breath-based mindfulness bodyscan, and constructive worry, would decrease sleep-onset latency and pre-sleep arousal similarly over time, relative to the control condition. A significant interaction was observed among adolescents with prolonged sleep-onset latency, who completed ≥3 days for at least 1 week (p = .001), where mindfulness decreased sleep-onset latency relative to constructive worry and the control. Neither technique changed pre-sleep worry or cognitive-emotional arousal, or associated daytime functioning (both the whole sample and sub-sample). A pre-recorded mp3 breath-based mindfulness bodyscan technique is a promising means by which adolescents with prolonged sleep-onset latency can decrease sleep-onset latency. This simple tool has potential for scalable dissemination by stakeholders (e.g. teachers), unqualified to treat adolescent sleep difficulties. Future studies are needed to determine whether benefits may extend to academic performance and mental health, if performed for a longer time period with increased compliance.

Self-administered acupressure for insomnia disorder: a pilot randomized controlled trial.

Self-administered acupressure has potential as a low-cost alternative treatment for insomnia. To evaluate the short-term effects of self-administered acupressure for alleviating insomnia, a pilot randomized controlled trial was conducted. Thirty-one subjects (mean age: 53.2 years; 77.4% female) with insomnia disorder were recruited from a community. The participants were randomized to receive two lessons on either self-administered acupressure or sleep hygiene education. The subjects in the self-administered acupressure group (n = 15) were taught to practise self-administered acupressure daily for 4 weeks. The subjects in the comparison group (n = 16) were advised to follow sleep hygiene education. The primary outcome was the Insomnia Severity Index (ISI). Other measures included a sleep diary, Hospital Anxiety and Depression Scale and Short-form Six-Dimension. The subjects in the self-administered acupressure group had a significantly lower ISI score than the subjects in the sleep hygiene education group at week 8 (effect size = 0.56, P = 0.03). However, this observed group difference did not reach a statistically significant level after Bonferroni correction. With regard to the secondary outcomes, moderate between-group effect sizes were observed in sleep onset latency and wake after sleep onset based on the sleep diary, although the differences were not significant. The adherence to self-administered acupressure practice was satisfactory, with 92.3% of the subjects who completed the lessons still practising acupressure at week 8. In conclusion, self-administered acupressure taught in a short training course may be a feasible approach to improve insomnia. Further fully powered confirmatory trials are warranted.

The SENSE Study: Treatment Mechanisms of a Cognitive Behavioral and Mindfulness-Based Group Sleep Improvement Intervention for At-Risk Adolescents.

Objectives: The aim of this study was to test whether a cognitive behavioral and mindfulness-based group sleep intervention would improve sleep and anxiety on school nights in a sample of at-risk adolescents. We also examined whether benefits to sleep and anxiety would be mediated by improvements in sleep hygiene awareness and presleep hyperarousal. Methods: Secondary analysis of a randomized controlled trial conducted with 123 adolescent participants (female = 60%; mean age = 14.48) who had high levels of sleep problems and anxiety symptoms. Participants were randomized into a sleep improvement intervention (n = 63) or active control "study skills" intervention (n = 60). Preintervention and postintervention, participants completed the Pittsburgh Sleep Quality Index (PSQI), Spence Children's Anxiety Scale (SCAS), Sleep Beliefs Scale (SBS), and Presleep Hyperarousal Scale (PSAS) and wore an actiwatch and completed a sleep diary for five school nights. Results: The sleep intervention condition was associated with significantly greater improvements in actigraphy-measured sleep onset latency (SOLobj), sleep diary measured sleep efficiency (SEsubj), PSQI, SCAS, SBS, and PSAS, with medium to large effect sizes. Improvements in the PSQI and SCAS were specifically mediated by the measured improvements in the PSAS that resulted from the intervention. Improvements in SOLobj and SEsubj were not specifically related to improvements in any of the putative treatment mechanisms. Conclusions: This study provides evidence that presleep arousal but not sleep hygiene awareness is important for adolescents' perceived sleep quality and could be a target for new treatments of adolescent sleep problems.

Two hours of evening reading on a self-luminous tablet vs. reading a physical book does not alter sleep after daytime bright light exposure.

BACKGROUND: The use of electronic devices emitting blue light during evening hours has been associated with sleep disturbances in humans, possibly due to the blue light-mediated suppression of the sleep-promoting hormone melatonin. However, experimental results have been mixed. The present study therefore sought to investigate if reading on a self-luminous tablet during evening hours would alter sleepiness, melatonin secretion, nocturnal sleep, as well as electroencephalographic power spectral density during early slow-wave sleep. METHODS: Following a constant bright light exposure over 6.5 hours (~569 lux), 14 participants (six females) read a novel either on a tablet or as physical book for two hours (21:00-23:00). Evening concentrations of saliva melatonin were repeatedly measured. Sleep (23:15-07:15) was recorded by polysomnography. Sleepiness was assessed before and after nocturnal sleep. About one week later, experiments were repeated; participants who had read the novel on a tablet in the first experimental session continued reading the same novel in the physical book, and vice versa. RESULTS: There were no differences in sleep parameters and pre-sleep saliva melatonin levels between the tablet reading and physical book reading conditions. CONCLUSIONS: Bright light exposure during daytime has previously been shown to abolish the inhibitory effects of evening light stimulus on melatonin secretion. Our results could therefore suggest that exposure to bright light during the day - as in the present study - may help combat sleep disturbances associated with the evening use of electronic devices emitting blue light. However, this needs to be validated by future studies with larger sample populations.