Sleep

Individual sleep need and sleep duration jointly predict risk-related decision making, and there was a significant interaction between them. Using a longitudinal design with a sample of 166 college students, we found that college students with high sleep need who sleep less engage in more risky decisions than those who sleep more than 6 hours.

Emerging adults can benefit from a short nap during the day to make better plans and risk-related decisions. After a 90-minute nap, individuals showed improved planning capacity and steady response speeds in making risk-related decisions when compared to the young people who did not sleep during the day. The polysomnographic characteristics of the nap revealed a correlation between the amount of sleep spindles and changes in planning and risk-related decision-making. In addition, we found that there was about 66.2% with excessive daytime sleepiness, and 61.9% with poor sleep quality in our emerging adult sample. This research will help inform decisions about the use of strategic napping to improve daytime functioning and to compensate for inadequate nighttime sleep for young people.

Dispositional characteristics like emotional stability and social cynicism have been consistently associated with negative affect, which is a known predictor and outcome of poor sleep quality. This study hypothesized a bidirectional relationship of sleep quality with emotional stability and social cynicism over a five-year period. Participants were 7,181 Chinese people, who completed two waves of online surveys from a larger panel study. Questionnaires on Big Five personality traits, social cynicism, and sleep quality were administered twice at a five-year interval. Cross-lagged analysis revealed a significant bidirectional relationship between emotional stability and sleep quality over five years as hypothesized. However, there was no association between sleep quality and social cynicism in either direction. Our study provides consistent evidence of a bidirectional relationship between sleep quality and emotional stability in a five-year time frame among a younger population. Given the critical role of emotional stability in various areas of functioning, the findings highlight the importance of sleep health education in young adults who are going through a critical period of personality development.

Our study invited 2,804 students from local primary and secondary schools to investigate the associations of sleep with strengths and difficulties, hope and happiness. Well-slept children and teens reported 

• More prosocial behaviors

• Fewer emotional problems

• Fewer behavioural and conduct problems

We observed that sleep quality and sufficiency predicted hope and happiness. Our findings also highlighted the dual pathways by which good sleep contributes to hope and happiness both directly and indirectly through reducing emotional symptoms in school-aged children. Of note, students of senior grades sleep significantly less than those of junior grades. 

The role of sleep in depression is increasingly recognised but the underlying cognitive-emotive mechanisms are largely unknown. Using a napping paradigm, we found that a daytime sleep opportunity improved inhibitory control over emotional information among depressed emerging adults. Importantly, such improvement was associated with specific brain physiology during sleep. By elucidating the specific affective-cognitive processes that explain the sleep-depression link, this study offers new insights for the development of targeted interventions for depression. 

Individuals with depression interpret angry faces more intensely after a REM-containing daytime nap, whereas healthy adults experience angry faces more intensely after a 30-min nap without REM. In addition, the more REM sleep the depressed group get, the larger the increase in the intensity rating of angry faces. This research piece serves as an important step toward understanding the role of sleep in emotional processing in depression and providing a further basis for the transdiagnostic treatment of sleep in this clinical population.

This paper delves into the objective/subjective sleep problem and examines how anxiety and memory complaints with different subtypes of OCD affect sleep. The relationship between sleep problems and OCD-checking behaviour is first elucidated. We also found that the relationship between sleep problems and checking behaviours is mediated by subjective memory complaints and anxiety symptoms, which increases our understanding of the psychopathological mechanisms of OCD symptoms. 

Inadequate sleep has become more common among adolescents worldwide, especially in developed countries, who tend to report post-lunch sleepiness, reduced learning efficiency, and compromised academic performance. Our study showed that napping (<1 hour) is effective in relieving post-lunch sleepiness and beneficial for the consolidation of verbal declarative memory. Napping can, therefore, be used as a potential memory intervention or compensatory strategy when sleep deprivation is of important benefit to the sleep-academic balance of adolescents.

With resting-state EEG measures, heightened frontal theta/beta ratio and a trend towards more left-lateralized frontal alpha asymmetry were found after 24-hr sleep deprivation compared with well-rested sleep. It is suggested that the default mode of the emotion regulatory brain network may be physiologically compromised by sleep deprivation.