Sleep quality in eating disorders: A systematic review and meta-analysis.

Eating disorders (ED) are psychological disorders characterized by dangerous eating behaviours, including protracted fasting and binge eating. Mental disorders comorbidities (e.g., anxiety and depression), as well as sleep difficulties, are common and might interfere with treatment response. This work investigated sleep quality, circadian preferences, and sleep disorders in ED patients compared to healthy controls (HC) and the impact of ED treatment on patients' sleep. A literature search on Pubmed, Web of Science, Medline, and PsychInfo included 27 studies. Random effect analyses were performed (sample eating disorders = 711; sample healthy controls = 653) and subgroup analyses were calculated based on the ED subgroups: Anorexia Nervosa, Bulimia Nervosa, Binge Eating Disorder. Whole sample analyses showed poorer physiological and subjective sleep quality in patients. Subgroup analyses showed that poorer physiological sleep was present only in anorexia nervosa. Two studies reporting circadian preferences and sleep disorders showed higher evening preference in patients and no differences in apnea prevalence between patients and healthy controls, respectively. Some studies suggested that specialized eating disorder treatments (e.g., Cognitive Behavioural Therapy for ED) can improve sleep quality in patients. Although these findings highlight poorer sleep in patients with ED compared to healthy controls, the mechanisms underlying sleep alterations in eating disorders remain to be identified.

The impact of sleep on factual memory retention over 24 hr.

Although a period of sleep seems to benefit the retention of declarative memories, recent studies have challenged both the size of this effect and its active influence on memory consolidation. This study aimed to further investigate the effect of sleep and its time dependency on the consolidation of factual information. In a within-subjects design, 48 participants (Mage = 24.37 ± 4.18 years, 31F) were asked to learn several facts in a multi-sensory "flashcard-like" memory task at 21:00 hours (sleep first condition) or at 09:00 hours (wake first condition). Then, in each condition, participants performed an immediate recall test (T0), and two delayed tests 12 hr (T1) and 24 hr (T2) later. Participants' sleep was recorded at their homes with a portable device. Results revealed that memory retention was better after a night of sleep compared with wakefulness, regardless of the delay from encoding (a few hr versus 12+ hr), but the sleep effect was modest. The decline in memory during the wake period following sleep was smaller compared with the decline observed during the 12 hr of wakefulness after encoding. However, after 24 hr from the encoding, when all participants experienced a period of both sleep and wakefulness, memory performance in the two conditions was similar. Overall, our data suggest that sleep exerts a small, yet beneficial, influence on memory retention by likely reducing interference and actively stabilizing memory traces.

The role of sleep and wakefulness in the recognition of emotional pictures.

Sleep has a beneficial effect on memory consolidation. However, its role in emotional memory is currently debated. Here, we investigate the role of sleep and a similar period of wakefulness on the recognition of emotional pictures and subjective emotional reactivity. Forty participants without any major physical, neurological or psychological condition were randomly assigned to the Sleep First Group or Wake First Group. The two groups underwent the encoding phase of an emotional images task with negative and neutral pictures at either 09:00 hours (Wake First Group) or 21:00 hours (Sleep First Group). Then participants performed an immediate recognition test (T1), and two delayed tests 12 hr (T2) and 24 hr (T3) later. Perceived arousal and valence levels were collected for each picture. Sleep parameters were recorded at participants' homes with a portable device. No differences were observed at T1, whereas at T2 the Sleep First Group showed a higher memory performance than the Wake First Group. At T3, performance decreased in the Sleep First Group (who spent the previous 12 hr awake), but not in the Wake First Group (who slept during the previous 12 hr). Overall, negative images were remembered better than neutral ones. We also observed a positive association between memory performance for negative items at the immediate test and the percentage of rapid eye movement sleep the night before the encoding. Our data confirm that negative information is remembered better over time than neutral information, and that sleep benefits the retention of declarative information. However, sleep seems not to preferentially improve emotional memory, although it may affect the encoding of negative information.

Parsing variability in borderline personality disorder: a meta-analysis of neuroimaging studies.

Though a plethora of functional magnetic resonance imaging (fMRI) studies explored the neurobiological underpinnings of borderline personality disorder (BPD), findings across different tasks were divergent. We conducted a systematic review and activation likelihood estimation (ALE) meta-analysis on the fMRI studies conducted in BPD patients compared to healthy controls (HC). We systematically searched PubMed and PsychINFO from inception until July 9th 2020 using combinations of database-specific terms like 'fMRI', 'Neuroimaging', 'borderline'. Eligible studies employed task-based fMRI of the brain in participants of any age diagnosed with BPD compared to HC, during any behavioral task and providing a direct contrast between the groups. From 762 entries, we inspected 92 reports full-texts and included 52 studies (describing 54 experiments). Across all experiments, the HC > BPD and BPD > HC meta-analyses did not yield any cluster of significant convergence of differences. Analyses restricted to studies of emotion processing revealed two significant clusters of activation in the bilateral hippocampal/amygdala complex and anterior cingulate for the BPD > HC meta-analysis. Fail-safe N and single study sensitivity analysis suggested significant findings were not robust. For the subgroup of emotional processing experiments, on a restricted number of experiments providing results for each group separately, another meta-analysis method (difference of convergence) showed a significant cluster in the insula/inferior frontal gyrus for the HC > BPD contrast. No consistent pattern of alteration in brain activity for BPD was evidenced suggesting substantial heterogeneity of processes and populations studied. A pattern of amygdala dysfunction emerged across emotion processing tasks, indicating a potential pathophysiological mechanism that could be transdiagnostic.