Hampered gamma oscillations induced by sad emotion underlying suicide attempt in major depressive disorder.

AIM: Major depressive disorder (MDD) is associated with high suicidality, especially for those with suicide attempt (SA). Although impaired oscillatory activity has been previously reported in patients with SA, little is known about precise temporal-spatial variability of its neural dynamics. To solve this, the current study probed the spectral power and network interactions underlying SA in MDD. METHODS: The present study recruited 104 subjects including 56 subjects with MDD (30 with SA and 26 without SA) and 48 healthy controls, who performed sad expressions recognition task during magnetoencephalography (MEG) recording. By investigating source-reconstructed MEG-data, brain states representing different task stages were estimated from a Hidden Markov model. Spectrum power and network connectivity were compared via Gaussian Mixture Models, and fractional occupancy (FO) of states were compared via an independent F-test. RESULTS: Brain states were corresponding to various frequencies (theta/beta/low gamma/ high gamma). In low gamma band (35-45 Hz), the early visual state exhibited increased activation and hyper inter-network connectivity between visual regions and the limbic system, while the middle fronto-parietal state exhibited attenuated activation and decreased intra-network connectivity within fronto-parietal regions in SA group. Crucially, FO values of these two states were significantly correlated with the suicide risks. CONCLUSIONS: Suicide behavior of patients with MDD was significantly associated with aberrant oscillations in low gamma band. Elevated oscillations in occipital cortices and attenuated oscillations in fronto-parietal cortices were significantly associated with SA. Manifesting sadness indulging and reckless decision-making, the hampered temporal characteristics could help explain the neural-electric basis of SA.

Age-related emotional bias in associative memory consolidation: The role of sleep.

Sleep plays a crucial role in memory consolidation. However, the influence of sleep on emotional memory consolidation in older adults, especially in the context of associative memory, which is more cognitively demanding than item memory, remains elusive. For this study we recruited young and older adults, and randomly assigned them into the sleep or wake condition. They were administrated a visual-spatial associative memory task, which required them to remember a picture and its location. We measured memory performance for positive, neutral, and negative stimuli before and after a 12-h interval of being awake or asleep. An accuracy analysis indicated a beneficial effect of sleep on location memory regardless of age and valence. In addition, in a more fine-grained analysis, the drift rate from diffusion modeling showed that sleep facilitated the consolidation of negative stimuli in young adults, while this emotion bias shifted to positive stimuli in older adults. Moreover, negative correlations were observed between the change of memory performance and sleep characteristics in older adults, indicating that more sleep results in fewer negative memories. Our results provide a relatively weak support for an age-related emotional bias in the context of associative memory, manifested in the absence of an age-by-valence interaction in accuracy, whilst a modeling parameter in consideration of both accuracy and response time yielded evidence consistent with the predictions of the socioemotional selectivity theory.

Balancing Benefit vs Risk of Immunosuppressive Therapy for Individual Patients With Inflammatory Bowel Diseases.

Inflammatory bowel diseases (IBD) and their treatments, particularly immunosuppressive drugs, increase risk of infections and cancers. However, by promoting mucosal healing, these agents should reduce risks of infections related to intestinal lesions, malnutrition, intravenous devices, and IBD surgeries and reduce risk of cancers associated with chronic mucosal inflammation-although there are few data to support this concept. Corticosteroids increase the risk of vascular thromboembolic events, yet other immunosuppressive drugs that induce deep remission from IBD could decrease the incidence of cardiovascular events attributable to systemic inflammation and IBD-related hospitalizations and/or surgeries. The nature and magnitude of the risks of infections and cancers vary with immunosuppressive drug class and patient sex and age. For example, thiopurines increase risk of viral infections that might be fatal in young patients, whereas tumor necrosis factor antagonists increase risk of bacterial and intracellular infections that can be fatal in patients of any age, but particularly in older patients. The ability of drugs to prevent IBD-associated colorectal cancer varies with IBD location and duration. Models to assess the benefit:risk ratio of long-term use of immunosuppressive drugs for patients with IBD should be adapted based on patients' age, sex, and IBD phenotype, to properly guide patient management. The decision-making process should begin with a clear explanation of treatment risks and then integrate the patient's emotional perception of risks.

Differences in emotional stimuli processing in subjects with MTLE with and without depression.

In healthy people, a preference in attention maintenance and memory for words with emotional valence comparing to neutral words has been shown. The pattern of emotional stimuli processing may be different in people with mesial temporal lobe epilepsy (MTLE) and it may be sensitive to the presence of depressive symptoms. In order to explore these possibilities, we applied the emotional spatial cueing attentional task and the free recall memory task to participants (N=39) with MTLE and compared them with healthy controls. We hypothesized that the pattern of maintaining attention and remembering emotional words is different in people with MTLE. Current literature indicates that this pattern will change from positive bias in the controls, though no emotional bias in the participants with MTLE without depression (MTLE-d), and in this work we examined this pattern in the participants with MTLE with depressive symptoms (MTLE+d). Our results show that in both attention and memory, control subjects exhibit positive emotional bias, the subjects with MTLE-d show nonemotional bias and the subjects with MTLE+d have bias away from positive words. Participants with MTLE+d maintained attention for positive words shorter than others. Participants with MTLE+d had worse recall for positive words than the participants with MTLE-d and for all words when compared to controls. We found that faster attention disengagement from positive words and worse memory for positive words is associated with elevated levels of depressive symptoms.

Associations between mood instability and emotional processing in a large cohort of bipolar patients.

BACKGROUND: Aberrant emotional biases have been reported in bipolar disorder (BD), but results are inconsistent. Despite the clinical relevance of chronic mood variability in BD, there is no previous research investigating how the extent of symptom fluctuations in bipolar disorder might relate to emotional biases. This exploratory study investigated, in a large cohort of bipolar patients, whether instability in weekly mood episode symptoms and other clinical and demographic factors were related to emotional bias as measured in a simple laboratory task. METHOD: Participants (N = 271, BDI = 206, BDII = 121) completed an 'emotional categorization and memory' task. Weekly self-reported symptoms of depression and mania were collected prospectively. In linear regression analyses, associations between cognitive bias and mood variability were explored together with the influence of demographic and clinical factors, including current medication. RESULTS: Greater accuracy in the classification of negative words relative to positive words was associated with greater instability in depressive symptoms. Furthermore, greater negative bias in free recall was associated with higher instability in manic symptoms. Participants diagnosed with BDII, compared with BDI, showed overall better word recognition and recall. Current antipsychotic use was associated with reduced instability in manic symptoms but this did not impact on emotional processing performance. CONCLUSIONS: Emotional processing biases in bipolar disorder are related to instability in mood. These findings prompt further investigation into the underpinnings as well as clinical significance of mood instability.

Eye-tracking evidence of a relationship between attentional bias for emotional faces and depression severity in patients with treatment-resistant depression.

In a retrospective study, 54 patients with treatment-resistant major depressive disorder (TRD) completed a free-viewing task in which they had to freely explore pairs of faces (an emotional face (happy or sad) opposite to a neutral face). Attentional bias to emotional faces was calculated for early and sustained attention. We observed a significant negative correlation between depression severity as measured by the 10-item Montgomery-Åsberg Depression Rating Scale (MADRS) and sustained attention to happy faces. In addition, we observed a positive correlation between depression severity and sustained attention to sad faces. No significant correlation between depression severity and early attention was found for either happy or sad faces. Although conclusions from the current study are limited by the lack of comparison with a control group, the eye-tracking free-viewing task appears to be a relevant, accessible and easy-to-use tool for measuring depression severity through emotional attentional biases in TRD.

Suicide-related cognitions and emotional bias performance in a community sample.

BACKGROUND: Suicide is theorized to be connected to social interactions and feelings of belongingness. Those with suicide-related cognitions (SRCs) demonstrate attentional bias toward negative or suicide-related words, which can lead to increased feelings of rejection or alienation. As social interactions employ both verbal and nonverbal cues, there exists a gap in understanding how perception of emotional expressions can contribute to the development or exacerbation of suicidal ideation. METHODS: The current sample (N = 114, 60.5 % female, 74.6 % white) completed the Suicide Cognitions Scale-Revised (SCS-R) and Patient Health Questionnaire (PHQ-9) to assess SRCs and depression severity. The Emotional Bias Task (EBT) was used to assess emotional response latency. RESULTS: Multiple regression analyses on EBT results showed that endorsement of SRCs and depression severity were not associated with any particular emotional response bias. However, presence of SRCs showed an association with longer latencies to identify ambiguous emotional expressions, even when controlling for depressive symptoms and age LIMITATIONS: Measures were self-completed online. Relative homogeneity of the sample and cross-sectional design limits interpretation of the results. CONCLUSIONS: Those with more severe SRCs take longer to recognize positive, nonverbal cues. Irregular processing of positive emotional stimuli combined with bias toward negative verbal cues could worsen feelings of rejection or alienation in social interactions, therefore increasing risk of developing SI. This suggests that interventions focusing on allocation of attentional resources to process positive social cues may be beneficial for those with SRCs to reduce severity and risk of suicide.

The Role of Working Memory in Age-Related Emotional Memory Bias.

Aging is accompanied by deterioration in both working memory (WM) and long-term memory (LTM), yet whether these changes are related is not understood. Sleep plays a role in the formation of LTM in young adults, but the findings in older adults are not as clear. The types of memories we store also shift with age as young adults preserve a higher proportion of negative experiences when compared to older adults. The reason for this age-related change in emotional memory bias is also not clear; however, some studies have suggested that WM changes across aging may be an important factor. In the current study, we examined performance in WM and emotional LTM in younger and older adults. We added a daytime nap in half the subjects to examine a possible role of sleep on emotional LTM. In the morning, 93 younger (18-39) and 121 older (60-85) adults completed a WM task. Subjects also encoded neutral or negative word pairs and provided valence and arousal ratings for each pair. After half the subjects took a daytime nap, LTM was examined, and valence and arousal ratings were reassessed. Results indicate that older adults showed worse recognition for negative word pairs compared with neutral, as well as decreased negative valence ratings in the afternoon. This decrease in emotional reactivity was correlated with better LTM performance. In contrast, younger adults performed better on the negative compared to neutral word pairs, with no change in emotional reactivity and no association between emotional reactivity and LTM. In addition, WM was positively related to LTM in younger, but not in older adults. Lastly, no differences were shown across sleep, regardless of age. Our findings suggest that the emotional memory bias may be associated with the emotional saliency of the information in older adults, and with WM capacity in younger adults. Supplementary Information: The online version contains supplementary material available at 10.1007/s42761-022-00134-5.

An Emotional Bias Modification for Children With Attention-Deficit/Hyperactivity Disorder: Co-design Study.

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) is one of the common neurodevelopment disorders. Children with ADHD typically have difficulties with emotional regulation. Previous studies have investigated the assessment for underlying emotional biases using the visual probe task. However, one of the significant limitations of the visual probe task is that it is demanding and repetitive over time. Previous studies have examined the use of gamification methods in addressing the limitations of the emotional bias visual probe task. There has also been increased recognition of the potential of participatory action research methods and how it could help to make the conceptualized interventions more relevant. OBJECTIVE: The primary aim of this study was to collate health care professionals' perspectives on the limitations of the existing visual probe task and to determine if gamification elements were viable to be incorporated into an emotional bias modification task. METHODS: A co-design workshop was conducted. Health care professionals from the Department of Development Psychiatry, Institute of Mental Health, Singapore, were invited to participate. Considering the COVID-19 pandemic and the restrictions, a web-based workshop was conducted. There were 3 main phases in the workshops. First, participants were asked to identify limitations and suggest potential methods to overcome some of the identified limitations. Second, participants were shown examples of existing gaming interventions in published literature and commercial stores. They were also asked to comment on the advantages and limitations of these interventions. Finally, participants were asked if gamification techniques would be appropriate. RESULTS: Overall, 4 health care professionals consented and participated. Several limitations were identified regarding the conventional emotional bias intervention. These included the nature of the task parameters, included stimulus set, and factors that could have an impact on the accuracy of responding to the task. After examining the existing ADHD games, participants raised concerns about the evidence base of some of the apps. They articulated that any developed ADHD game ought to identify the specific skill set that was targeted clearly. Regarding gamification strategies, participants preferred economic and performance-based gamification approaches. CONCLUSIONS: This study has managed to elucidate health care professionals' perspectives toward refining a conventional emotional bias intervention for children with ADHD. In view of the repetitiveness of the conventional task, the suggested gamification techniques might help in influencing task adherence and reduce the attrition rates.

Gut Feelings: Vagal Stimulation Reduces Emotional Biases.

The vagus nerve is a key physical constituent of the gut-brain axis. Increasing attention has recently been paid to the role that the gut, and the microorganisms inhabiting it, play in emotion and cognition. Animal studies have revealed the importance of the vagus nerve in mediating communication between the gut microbiome and the central nervous system, resulting in changes in emotional behaviour. This has renewed interest in understanding the role of vagal signalling in human emotion, particularly since human studies have also shown that alterations in gut microbiome composition can affect emotion. While stimulating the vagus nerve can help treat some cases of severe depression, here we investigate whether vagal afferent signalling can influence emotional processing in healthy subjects. We use the dot-probe task to determine the effect of transcutaneous vagus nerve stimulation on attentional biases towards emotional stimuli in 42 volunteers. Participants received both active and sham treatments using a within-subject design. We show that transcutaneous vagus nerve stimulation reduces the emotional bias towards faces expressing sadness and happiness, indicating a decrease in emotional reactivity. While our novel findings reveal the effect that vagal signalling can have on emotional biases in healthy subjects, future studies should seek to develop our understanding of the ways in which the microbiome interacts with, and stimulates, the vagus nerve. Since we find a reduction in emotional bias, most notably towards sadness, this may partly account for the effective use of vagus nerve stimulation in treatment-resistant depression. While its clinical application currently involves surgical stimulation, our results support the potential benefit of transcutaneous vagus nerve stimulation as a non-invasive, intermittent adjunctive therapy for patients with depression, given its frequent association with emotional biases.

Interoception Dysfunction Contributes to the Negative Emotional Bias in Major Depressive Disorder.

Background: Previous research studies have demonstrated that impaired interoception is involved in emotional information processing in major depressive disorder (MDD). Heartbeat-evoked potential (HEP) amplitudes, an index for interoception, could be manipulated by emotional faces in healthy people. Considering negative emotional bias is the core characteristic in MDD, we hypothesized that interoception dysfunction was associated with the negative emotional bias in MDD. Methods: An electroencephalogram (EEG) study under an emotional faces task was applied to explore the relationship between interoception and emotional bias. HEPs before emotional faces stimuli were used to predict the late positive potential (LPP) amplitudes and it worked as an index of emotional bias. Twenty-seven patients with MDD and 27 healthy controls (HCs) participated in this study. Source analysis gave an auxiliary description for results in sensory level. Results: Major depressive disorders (MDDs) had poor performance in the heartbeat count task (HCT) and attenuate HEP average amplitudes (455-550 ms). Compared with HCs, cluster-based permutation t-tests revealed that MDDs had attenuated LPP amplitudes (300-1,000 ms) over centroparietal regions and enhanced LPP amplitudes over frontocentral regions. Furthermore, abnormal attenuated HEPs could predict aberrant LPPs under sad face stimuli in MDDs, which could be associated with the dysfunction of the anterior cingulate cortex (ACC) and right insula. Conclusion: Mediated by ACC and insula, interoception dysfunction contributes to the negative emotional bias of MDD, highlighting the importance of interoception in the disorder.

Emotional Bias Modification for Individuals With Attention Deficit Hyperactivity Disorder: Protocol for a Co-Design Study.

BACKGROUND: Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder with a worldwide prevalence rate of 5%. Individuals with ADHD often tend to have difficulties with emotional regulation. The advances in experimental psychology have led to the discovery of emotional biases. Targeting emotional biases could potentially help improve the core symptoms of irritability and short-temperedness among these individuals. Emotional biases refer to the preferential allocation of attention toward emotional stimuli. A recent study reported the presence of emotional biases among individuals with ADHD when they compared individuals with ADHD with those without. Gamification technologies have been explored to help diminish the repetitiveness of the task and increase the intrinsic motivation to train. These inconsistent findings of the impact of gaming on the effectiveness of mobile interventions call for further work to better understand the needs of patients (users) and health care professionals. OBJECTIVE: The aim of this research study is to collate health care professionals' perspectives on the limitations of the existing task, and to determine if gamification elements could be incorporated, to refine the conventional intervention. METHODS: A qualitative research approach, that of a focus group, will be used. Health care professionals from the Department of Development Psychiatry, Institute of Mental Health, Singapore will be invited to participate in this qualitative research. During the focus group, participants are to comment on the limitations of the existing emotional bias intervention; recommend strategies to improve the intervention; and provide their perspectives pertaining to the use of gamification to improve the intervention. RESULTS: We expect that the study will be completed in 12 months from the publication of this protocol. CONCLUSIONS: To our best knowledge, this is perhaps one of the only few studies that have attempted to explore emotional biases among adolescents with ADHD. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/24078.

Emotional Bias Modification in Youths with Attention Deficit Hyperactivity Disorder (ADHD): New Research Vista.

Whilst cognitive bias modification was initially used in the treatment of anxiety disorders, it is also currently being used for the treatment of other psychopathologies. In fact, cognitive bias modification has been especially well-investigated amongst children and adolescents. A recent review suggests some evidence for the modification of interpretative biases amongst children with neurodevelopment disorders. There have since been other studies reporting of the existence of other cognitive biases, such as emotional biases, amongst individuals with attention deficit hyperactivity disorder (ADHD). This perspective article will discuss the epidemiology of ADHD and the nature of emotional biases that are present amongst individuals with ADHD. This perspective article also reviewed some of the studies that have assessed and modified emotional biases in individuals with ADHD. A total of three studies have been identified from the published literature that provide evidence for targeting emotional biases amongst individuals with ADHD. These studies provide us with preliminary evidence for the effectiveness of modifying emotional biases and how it could help in ameliorating symptoms related to emotional dysregulation. There needs to be future research in this area with further evidence supporting the effectiveness of modifying emotional biases. It is also crucial for future research to determine which of these tools is best at detecting such biases, and which of these tools are versatile enough and non-invasive that they could safely be implemented for both research and clinical needs.

Predicting treatment response to antidepressant medication using early changes in emotional processing.

Antidepressants must be taken for weeks before response can be assessed with many patients not responding to the first medication prescribed. This often results in long delays before effective treatment is started. Antidepressants induce changes in the processing of emotional stimuli early in the course of treatment. In the current study we assessed whether changes in emotional processing and subjective symptoms over the first week of antidepressant treatment predicted clinical response after 4-8 weeks of treatment. Such a predictive test may shorten the time taken to initiate effective treatment in depressed patients. Seventy-four depressed primary care patients completed measures of emotional bias and subjective symptoms before starting antidepressant treatment and then again 1 week later. Response to treatment was assessed after 4-6 weeks. The performance of classifiers based on these measures was assessed using a leave-one-out validation procedure with the best classifier then tested in an independent sample from a second study of 239 patients. The combination of a facial emotion recognition task and subjective symptoms predicted response with 77% accuracy in the training sample and 60% accuracy in the independent study, significantly better than possible using baseline response rates. The face based measure of emotional bias provided good quality data with high acceptability ratings. Changes in emotional processing can provide a sensitive early measure of antidepressant efficacy for individual patients. Early treatment induced changes in emotional processing may be used to guide antidepressant therapy and reduce the time taken for depressed patients to return to good mental health.

Emotional Biases and Recurrence in Major Depressive Disorder. Results of 2.5 Years Follow-Up of Drug-Free Cohort Vulnerable for Recurrence.

An interesting factor explaining recurrence risk in Major Depressive Disorder (MDD) may be neuropsychological functioning, i.e., processing of emotional stimuli/information. Negatively biased processing of emotional stimuli/information has been found in both acute and (inconclusively) remitted states of MDD, and may be causally related to recurrence of depression. We aimed to investigate self-referent, memory and interpretation biases in recurrently depressed patients in remission and relate these biases to recurrence. We included 69 remitted recurrent MDD-patients (rrMDD-patients), 35-65 years, with ≥2 episodes, voluntarily free of antidepressant maintenance therapy for at least 4 weeks. We tested self-referent biases with an emotional categorization task, bias in emotional memory by free recall of the emotion categorization task 15 min after completing it, and interpretation bias with a facial expression recognition task. We compared these participants with 43 never-depressed controls matched for age, sex and intelligence. We followed the rrMDD-patients for 2.5 years and assessed recurrent depressive episodes by structured interview. The rrMDD-patients showed biases toward emotionally negative stimuli, faster responses to negative self-relevant characteristics in the emotional categorization, better recognition of sad faces, worse recognition of neutral faces with more misclassifications as angry or disgusting faces and less misclassifications as neutral faces (0.001 < p < 0.05). Of these, the number of misclassifications as angry and the overall performance in the emotional memory task were significantly associated with the time to recurrence (p ≤ 0.04), independent of residual symptoms and number of previous episodes. In a support vector machine data-driven model, prediction of recurrence-status could best be achieved (relative to observed recurrence-rate) with demographic and childhood adversity parameters (accuracy 78.1%; 1-sided p = 0.002); neuropsychological tests could not improve this prediction. Our data suggests a persisting (mood-incongruent) emotional bias when patients with recurrent depression are in remission. Moreover, these persisting biases might be mechanistically important for recurrence and prevention thereof.

Emotional bias varies with stimulus type, arousal and task setting: Meta-analytic evidences.

Emotional bias, which describes human's asymmetric processing of emotional stimuli, consists of negativity bias (Increased response to negative over positive stimuli) and positivity offset (the reversed phenomenon). Previous studies suggest that stimulus arousal (high/low), stimulus type (scenic/verbal), cultural background (Eastern/Western), and task setting (explicit/implicit) may modulate emotional bias, but with inconclusive findings. To address how the profile of emotional bias varies with these factors, a meta-analysis of emotional P3 event-related potential amplitudes was performed. Forty-nine effect sizes from 38 studies involving 1263 subjects were calculated using Hedges'g. The results highlight significant moderators of arousal, stimulus type, and task setting. Specifically, high-arousal stimuli enhance negativity bias relative to low-arousal stimuli; scenic stimulus leads to a negativity bias while verbal stimulus is linked with a positivity offset; explicit emotion tasks lead to negativity bias, whereas implicit emotion tasks do not exhibit emotional bias. These results indicate that emotional bias is labile depending on stimulus arousal, stimulus type and task setting. The implication of these findings for emotion regulation is discussed.

An experimental investigation into the transmission of antivax attitudes using a fictional health controversy.

RATIONALE: Although vaccines are an invaluable weapon in combatting diseases, they are often surrounded by controversy. Vaccine controversies usually arise with the claims of some parents or doctors who link vaccines to harmful outcomes. These controversies often negatively affect vaccination coverage. OBJECTIVES: This experiment simulated a vaccine controversy to understand which content features of vaccination-related information are well transmitted and how this transmission affects vaccine intention. METHOD: All participants (N = 64) read two conflicting views (pro- and anti-) about a fictional vaccine ('dipherpox vaccine'). These conflicting views were held by a parent and a doctor, whose views varied across conditions. This information was transmitted along linear chains of four participants who recalled it and the product of their recall was passed to the next participant within their chain. They also responded whether they would vaccinate or not. RESULTS: The experience-based view held by the parent was better transmitted than the medical-based view held by the doctor, while the pro-vaccine and anti-vaccine views were similarly transmitted. Despite all the participants having neutral or positive attitudes towards vaccines in general, 39.1% of them decided not to vaccinate. Nevertheless, vaccination attitude was the strongest predictor of vaccination intention. The less positive participants' attitudes were towards vaccines in general, the less likely they were to vaccinate against dipherpox after exposure to the controversy. CONCLUSION: The results suggest that vaccination campaigns may be made more effective by including personal experiences of the negative consequences of non-vaccination.

Early life stress explains reduced positive memory biases in remitted depression.

BACKGROUND: There is contradictory evidence regarding negative memory biases in major depressive disorder (MDD) and whether these persist into remission, which would suggest their role as vulnerability traits rather than correlates of mood state. Early life stress (ELS), common in patients with psychiatric disorders, has independently been associated with memory biases, and confounds MDD versus control group comparisons. Furthermore, in most studies negative biases could have resulted from executive impairments rather than memory difficulties per se. METHODS: To investigate whether memory biases are relevant to MDD vulnerability and how they are influenced by ELS, we developed an associative recognition memory task for temporo-spatial contexts of social actions with low executive demands, which were matched across conditions (self-blame, other-blame, self-praise, other-praise). We included fifty-three medication-free remitted MDD (25 with ELS, 28 without) and 24 healthy control (HC) participants without ELS. RESULTS: Only MDD patients with ELS showed a reduced bias (accuracy/speed ratio) towards memory for positive vs. negative materials when compared with MDD without ELS and with HC participants; attenuated positive biases correlated with number of past major depressive episodes, but not current symptoms. There were no biases towards self-blaming or self-praising memories. CONCLUSIONS: This demonstrates that reduced positive biases in associative memory were specific to MDD patients with ELS rather than a general feature of MDD, and were associated with lifetime recurrence risk which may reflect a scarring effect. If replicated, our results would call for stratifying MDD patients by history of ELS when assessing and treating emotional memories.

Emotional bias of sleep-dependent processing shifts from negative to positive with aging.

Age-related memory decline has been proposed to result partially from impairments in memory consolidation over sleep. However, such decline may reflect a shift toward selective processing of positive information with age rather than impaired sleep-related mechanisms. In the present study, young and older adults viewed negative and neutral pictures or positive and neutral pictures and underwent a recognition test after sleep or wake. Subjective emotional reactivity and affect were also measured. Compared with waking, sleep preserved valence ratings and memory for positive but not negative pictures in older adults and negative but not positive pictures in young adults. In older adults, memory for positive pictures was associated with slow wave sleep. Furthermore, slow wave sleep predicted positive affect in older adults but was inversely related to positive affect in young adults. These relationships were strongest for older adults with high memory for positive pictures and young adults with high memory for negative pictures. Collectively, these results indicate preserved but selective sleep-dependent memory processing with healthy aging that may be biased to enhance emotional well-being.