Sleep and Affective Brain Regulation

Negative expressions are shared more on Twitter for public figures than for ordinary users

Social media users tend to produce content that contains more positive than negative emotional language. However, negative emotional language is more likely to be shared. To understand why, research has thus far focused on psychological processes associated with tweets' content. In the current study, we investigate if the content producer influences the extent to which their negative content is shared. More specifically, we focus on a group of users that are central to the diffusion of content on social media-public figures. We found that an increase in negativity was associated with a stronger increase in sharing for public figures compared to ordinary users. This effect was explained by two user characteristics, the number of followers and thus the strength of ties and the proportion of political tweets. The results shed light on whose negativity is most viral, allowing future research to develop interventions aimed at mitigating overexposure to negative content.

Dreaming during COVID-19: the effects of a world trauma

On March 11, 2020, the World Health Organization (WHO) declared a state of health emergency affecting the entire world population. Given the serious practical and psychological difficulties and complications that have been experienced during this period, many scholars have created hypothesis, as a consequence, an increased possibility of developing post-traumatic stress disorder (PTSD) within the general population with significant implications for one's dream activity. Participants in the study were recruited via the instant messaging application 'WhatsApp' for a period of 14 days. The study consisted of three phases: the first phase provided information on the purpose of the research and how to carry it out; in the second phase, each participant, using the Bionian model of dream experience as a focus, was asked to write down dreams, emotions and free connections/associations related to the dream. At the end of the collection, the texts obtained were analysed by means of a qualitative analysis performed with the aid of the MAXQDA software. The study confirms the computational and exploratory analysis of the text carried out in the research of Pesonen et al. (2020), finding also in our sample the presence of the hypothesized clusters going to explain the manifestation of imagery related to COVID-19 also within the dream activity. To confirm this, the nightmare of participant number 6 of the study is reported. The following qualitative research has offered an insight into the traumatic nature of the COVID-19 pandemic, showing how many unmetabolized 'daytime elements' have been reproposed in the dream scenario, recalling the symptomatology of PTSD through the presence of distressing content that affect the quality of sleep and the daily life of the individual.

Context matters: Self-regulation of healthy eating at different eating occasions

Self-regulation plays an important role in healthy eating behaviors. The current research explores temporary fluctuations in self-regulation next to variations between individuals. In an online observational study, 892 participants (M^age  = 44.3, SD^age  = 12.7) monitored their self-regulation three times a week before a meal moment for 3 weeks. To analyze the data, a random intercept and slopes model was used, including variables on within-individual level (i.e. meal moment, tiredness, distractedness, social, and physical environment) and variables on between-individual level (i.e. self-efficacy, intrinsic motivation, and perception of social and physical opportunity). Self-regulation was found to be higher at breakfast compared with dinner (estimate = -0.08, p < .001), higher at home than out-of-home (estimate = -0.08, p < .001) and lower when individuals are more tired (estimate = 0.04, p < .001) and distracted (estimate = 0.07, p < .001). Moreover, self-regulation was higher for individuals with higher levels of intrinsic motivation (estimate = 0.19, p < .001) and self-efficacy (estimate = 0.41, p < .001). Insights from this research advance our knowledge regarding temporal influences on self-regulation and can provide input for behavior change tools such as personalized dietary advice.

Three Reasons to Consider the Role of Tiredness in Sexual Risk-Taking Among Gay and Bisexual Men

Numerous factors have been shown to increase sexual risk-taking-especially among gay and bisexual men (GBM), who remain disproportionately affected by HIV and STIs. We present three lines of evidence that highlight the need to consider a previously under-explored situational factor in sexual risk-taking: tiredness. While tiredness has been shown, in sleep science literature, to impair cognition, emotional functioning, and decision-making in a wide range of behaviors, it has yet to be considered in-depth as a risk factor in sexual behavior. Counter to the common-sense assumption that being tired should impede the performance of active, effortful behaviors such as sex, we propose that tiredness may actually increase sexual risk-taking. Analyzing data from an online survey of 1113 HIV-negative GBM, we found that sex with casual partners most commonly occurred at night, especially among younger GBM and those with an evening chronotype, and that sex without condoms more often occurred at or later than one's usual time of feeling tired (as was reported by 44.2% of men) than did sex with condoms (reported by 36.6%). We also found that tiredness can increase sexual desire in many GBM (endorsed by 29.9%), and increases the likelihood of engaging in receptive positioning in anal sex (endorsed by almost 40% of men with a versatile sexual positioning identity). These findings highlight the importance of considering tiredness as a situational risk factor in sexual health-especially among younger GBM-and of counting sex among the behaviors that can be adversely impacted by poor or overdue sleep.

Neurophysiological differences in the adolescent brain following a single night of restricted sleep - A 7T fMRI study

Sleep deprivation in youth has garnered international attention in recent years, as correlational studies have demonstrated significant relationships between lack of sleep and detrimental behavioral and academic outcomes. However, no study to date has systematically examined the neurophysiological consequences of a single night of sleep restriction (i.e., 4 h) in adolescents using ultra-high field functional neuroimaging. Much of what we know regarding the neural consequences of sleep deprivation has come from the adult literature, and among those studies, the majority use region of interest (ROI) approaches, thus disregarding the dynamic mechanisms that may subserve the behavioral effects of sleep restriction. Leveraging a crossover within-subjects design, we demonstrate that pivotal brain regions involved in the default mode and limbic regulatory centers have disrupted functioning following a night of restricted sleep compared to a night of "normal sleep". Specifically, a normal night (i.e., 8 h) of sleep led to increased global and local efficiency of bilateral amygdala, and less efficiency in the posterior cingulate, as measured by graph theory, compared to a night of sleep restriction. Furthermore, aberrant functional connectivity patterns were identified in key fronto-limbic circuitry, suggesting a potential pathophysiological mechanism underlying the widespread effects of sleep deprivation in youth.

The mechanisms of action underlying the efficacy of psychological nightmare treatments: A systematic review and thematic analysis of discussed hypotheses

Studies of psychotherapeutic treatments for nightmares have yielded support for their effectiveness. However, no consensus exists to explain how they work. This study combines a systematic review with a qualitative thematic analysis to identify and categorize the existing proposed mechanisms of action (MAs) of nightmare treatments. The systematic review allowed for a great number of scholarly publications on supported psychological treatments for nightmares to be identified. Characteristics of the study and citations regarding potential MAs were extracted using a standardized coding grid. Then, thematic analysis allowed citations to be grouped under six different categories of possible MAs according to their similarities and differences. Results reveal that an increased sense of mastery was the most often cited hypothesis to explain the efficacy of nightmare psychotherapies. Other mechanisms included emotional processing leading to modification of the fear structure, modification of beliefs, restoration of sleep functions, decreased arousal, and prevention of avoidance. An illustration of the different variables involved in the treatment of nightmares is proposed. Different avenues for operationalization of these MAs are put forth to enable future research on nightmare treatments to measure and link them to efficacy measures, and test the implications of the illustration.

Sleep-dependent memory consolidation and its implications for psychiatry

Both sleep disturbance and memory impairment are very common in psychiatric disorders. Since sleep has been shown to play a role in the process of transferring newly acquired information into long-term memory, i.e., consolidation, it is important to highlight this link in the context of psychiatric disorders. Along these lines, after providing a brief overview of healthy human sleep, current neurobiological models on sleep-dependent memory consolidation and resultant opportunities to manipulate the memory consolidation process, recent findings on sleep disturbances and sleep-dependent memory consolidation in patients with insomnia, major depression, schizophrenia, and post-traumatic stress disorder are systematically reviewed. Furthermore, possible underlying neuropathologies and their implications on therapeutic strategies are discussed. This review aims at sensitizing the reader for recognizing sleep disturbances as a potential contributor to cognitive deficits in several disorders, a fact which is often overlooked up to date.

Metaphor and hyperassociativity: the imagination mechanisms behind emotion assimilation in sleep and dreaming

In this paper we propose an emotion assimilation function of sleep and dreaming. We offer explanations both for the mechanisms by which waking-life memories are initially selected for processing during sleep, and for the mechanisms by which those memories are subsequently transformed during sleep. We propose that emotions act as a marker for information to be selectively processed during sleep, including consolidation into long term memory structures and integration into pre-existing memory networks; that dreaming reflects these emotion assimilation processes; and that the associations between memory fragments activated during sleep give rise to measureable elements of dream metaphor and hyperassociativity. The latter are a direct reflection, and the phenomenological experience, of emotional memory assimilation processes occurring during sleep. While many theories previously have posited a role for emotion processing and/or emotional memory consolidation during sleep and dreaming, sleep theories often do not take enough account of important dream science data, yet dream research, when conducted systematically and under ideal conditions, can greatly enhance theorizing around the functions of sleep. Similarly, dream theories often fail to consider the implications of sleep-dependent memory research, which can augment our understanding of dream functioning. Here, we offer a synthesized view, taking detailed account of both sleep and dream data and theories. We draw on extensive literature from sleep and dream experiments and theories, including often-overlooked data from dream science which we believe reflects sleep phenomenology, to bring together important ideas and findings from both domains.

Sleep, arousal, and circadian rhythms in adults with obsessive-compulsive disorder: a meta-analysis

Findings of this meta-analysis show that obsessive-compulsive disorder (OCD) is related to disruptions in both the duration and timing of sleep. PsycINFO and Google Scholar database searches identified 12 relevant studies that compared measures of sleep in individuals with OCD to those of either a healthy control group or published norms. Sleep measures included sleep onset latency, sleep duration, awakening after sleep onset, percentage of rapid eye movement (REM) sleep, percentage of slow wave sleep, and prevalence of delayed sleep phase disorder (DSPD). Individual effect sizes were pooled using a random effects model. Sleep duration was found to be shorter, and the prevalence of DSPD higher, in individuals with OCD compared to controls. Further, excluding samples with comorbid depression did not meaningfully reduce the magnitude of these effects (although the results were no longer statistically significant) and medication use by participants is unlikely to have systematically altered sleep timing. Overall, available data suggest that sleep disruption is associated with OCD but further research on both sleep duration and sleep timing in individuals with OCD is needed.

The role of sleep in emotional brain function

Rapidly emerging evidence continues to describe an intimate and causal relationship between sleep and emotional brain function. These findings are mirrored by long-standing clinical observations demonstrating that nearly all mood and anxiety disorders co-occur with one or more sleep abnormalities. This review aims to (a) provide a synthesis of recent findings describing the emotional brain and behavioral benefits triggered by sleep, and conversely, the detrimental impairments following a lack of sleep; (b) outline a proposed framework in which sleep, and specifically rapid-eye movement (REM) sleep, supports a process of affective brain homeostasis, optimally preparing the organism for next-day social and emotional functioning; and (c) describe how this hypothesized framework can explain the prevalent relationships between sleep and psychiatric disorders, with a particular focus on posttraumatic stress disorder and major depression.