Anhedonia, defined as a loss of interest and pleasure in previously enjoyable activities, is a core symptom of depression that predicts a poor treatment response in adolescents. We know little about ...the cognitive vulnerability factors that contribute to the development of anhedonia in youth. This cross-sectional and longitudinal survey study investigated the link between anhedonia symptoms and cognitive appraisal of positive affect.
Baseline data were collected from 392 secondary school students in the UK (aged 13–16, 54 % Female), 170 of whom went on to complete the three-month follow-up assessment (a 43 % response rate). Participants rated their anhedonia symptoms and appraisal styles which were measured in terms of use of amplifying appraisals, dampening appraisals, and fear of positive emotion.
At baseline, greater anhedonia was significantly associated with increased levels of dampening and reduced levels of amplifying but was not significantly related to fear of positive emotion. Prospectively, greater baseline levels of amplifying uniquely predicted lower anhedonia severity at three-month follow-up, and vice-versa. There was no evidence for reciprocal prospective associations between anhedonia and, appraisal styles of dampening and fear of positive emotion.
These results indicate that cognitive appraisal of positive affect is associated with concurrent and to some extent can predict future symptoms of anhedonia in youth.
Investigations of fear conditioning in rodents and humans have illuminated the neural mechanisms underlying cued and contextual fear. A critical question is how personality dimensions such as trait ...anxiety act through these mechanisms to confer vulnerability to anxiety disorders, and whether humans' ability to overcome acquired fears depends on regulatory skills not characterized in animal models. In a neuroimaging study of fear conditioning in humans, we found evidence for two independent dimensions of neurocognitive function associated with trait vulnerability to anxiety. The first entailed increased amygdala responsivity to phasic fear cues. The second involved impoverished ventral prefrontal cortical (vPFC) recruitment to downregulate both cued and contextual fear prior to omission (extinction) of the aversive unconditioned stimulus. These two dimensions may contribute to symptomatology differences across anxiety disorders; the amygdala mechanism affecting the development of phobic fear and the frontal mechanism influencing the maintenance of both specific fears and generalized anxiety.
► Amygdala and frontal dysfunction independently linked to vulnerability to anxiety ► Amygdala dysregulation contributes to elevated cued fear in trait anxious subjects ► Anxiety resilience linked to greater vPFC activity during cued and contextual fear ► vPFC role not limited to extinction, but also pre-extinction fear downregulation
Two core features of depression include depressed mood (heightened distress) and anhedonia (reduced pleasure). Despite their centrality to depression, studies have not examined their contribution to ...treatment outcomes in a randomized clinical trial providing mainstream treatments like antidepressant medications (ADM) and cognitive therapy (CT). We used baseline distress and anhedonia derived from a factor analysis of the Mood and Anxiety Symptom Questionnaire to predict remission and recovery in 433 individuals with recurrent/chronic major depressive disorder. Patients were provided with only ADM or both ADM and CT. Overall, higher baseline distress and anhedonia predicted longer times to remission within one year and recovery within three years. When controlling for treatment condition, distress improved prediction of outcomes over and above anhedonia, while anhedonia did not improve prediction of outcomes over and above distress. Interactions with treatment condition demonstrated that individuals with higher distress and anhedonia benefited from receiving CT in addition to ADM, whereas there was no added benefit of CT for individuals with lower distress and anhedonia. Assessing distress and anhedonia prior to treatment may help select patients who will benefit most from CT in addition to ADM. For the treatments and outcome measures tested, utilizing distress to guide treatment planning may yield the greatest benefit.
clinicaltrials.gov Identifier: NCT00057577.
•Elevated distress and anhedonia predicted treatment outcomes in depressed persons.•Elevations predicted longer times to remission and recovery for up to 3 years.•Elevations predicted greater benefit from cognitive therapy in addition to medications.•Distress improved predictions of outcomes over and above anhedonia.•Anhedonia did not improve predictions of outcomes over and above distress.
Previous work has shown that dampening appraisals (e.g., thinking “this is too good to last”) reduce happiness and enhance sadness when adults recall positive events. In contrast, amplifying ...appraisals (e.g., thinking “this is the sign of good things to come”) do not significantly alter affective experience during the same task. The present study examined whether this pattern holds in adolescence. Eighty-nine adolescents completed an uninstructed positive recall task before being randomized to either dampening, uninstructed control or amplifying instructions during a second positive recall task. Participants experienced a significantly smaller increase in happiness and a significantly less marked reduction in sadness when recalling a positive memory under dampening instructions, relative to both the amplifying and no instruction control conditions. There was no significant difference between the amplifying and control conditions. This broadly replicates adult findings, but the detrimental effects of dampening were less marked in adolescents than adults. Nevertheless, given that elevated dampening appraisals are associated with depressed mood, dampening may partly account for why depressed adolescents struggle to experience positive emotions, and represent a promising target for clinical intervention.
•Positive appraisal style was manipulated during positive recall in adolescents.•Dampening appraisals led to decreases in happiness and increases in sadness.•Dampening appraisals may explain why positive memory recall can backfire.
The desire to image specimens in liquids has led to the development of open-cell and closed-cell techniques in transmission electron microscopy (TEM). The closed-cell approach is currently more ...common in TEM and has yielded new insights into a number of biological and materials processes in liquid environments. The open-cell approach, which requires an environmental TEM (ETEM), is technically challenging but may be advantageous in certain circumstances due to fewer restrictions on specimen and detector geometry. Here, we demonstrate a novel approach to open-cell liquid TEM, in which we use salt particles to facilitate the in situ formation of droplets of aqueous solution that envelope specimen particles coloaded with the salt. This is achieved by controlling sample temperature between 1 and 10°C and introducing water vapor to the ETEM chamber above the critical pressure for the formation of liquid water on the salt particles. Our use of in situ hydration enables specimens to be loaded into a microscope in a dry state using standard 3 mm TEM grids, allowing specimens to be prepared using trivial sample preparation techniques. Our future aim will be to combine this technique with an in situ light source to study photocorrosion in aqueous environments.
Anhedonia, or reward system dysfunction, is associated with poorer treatment outcomes among depressed individuals. The role of anhedonia in treatment engagement, however, has not yet been explored. ...We review research on components of reward functioning impaired in depression, including effort valuation, reward anticipation, initial responsiveness, reward learning, reward probability, and reward delay, highlighting potential barriers to treatment engagement associated with these components. We then propose interventions to improve treatment initiation and continuation by addressing deficits in each component of reward functioning, focusing on modifications of existing evidence‐based interventions to meet the needs of individuals with heightened anhedonia. We describe potential settings for these interventions and times at which they can be delivered during the process of referring individuals to mental health treatment, conducting intakes or assessments, and providing treatment. Additionally, we note the advantages of using screening processes already in place in primary care, workplace, school, and online settings to identify individuals with heightened anhedonia who may benefit from these interventions. We conclude with suggestions for future research on the impact of anhedonia on treatment engagement and the efficacy of interventions to address it.
Practitioner points
Many depressed individuals who might benefit from treatment do not initiate it or discontinue early. One barrier to treatment engagement may be anhedonia, a core symptom of depression characterized by loss of interest or pleasure in usual activities.
We describe brief interventions to improve treatment engagement in individuals with anhedonia that can be implemented during the referral process or early in treatment.
We argue that interventions aiming to improve treatment engagement in depressed individuals that target anhedonia may be particularly effective.
Fatigue is common in adolescence and can be highly disabling if experienced persistently, with adverse psychosocial outcomes. There is a need to better understand what nonpharmacological treatments ...are available for adolescents suffering with persistent fatigue. The current review systematically identified, synthesised, and evaluated the evidence regarding nonpharmacological interventions for fatigue in adolescents, focusing on evaluating effectiveness, describing intervention components, and mapping interventions onto the behaviour change technique taxonomy (BCTT).
CENTRAL, EMBASE, PsycINFO, PubMed, and Web of Science were systematically searched for articles including (1) adolescents aged 10–19 years old, (2) fatigue as a primary or secondary outcome, (3) nonpharmacological interventions, and (4) randomised controlled trials. Study screening, data extraction, quality assessment, and BCTT mapping were performed independently by two reviewers. Findings were presented as a narrative synthesis, with interventions ranked by promise.
5626 papers were identified and double-screened, resulting in the inclusion of 21 articles reporting 16 trials. Five interventions were classified as likely promising. Interventions often involved psychoeducation, cognitive behavioural therapy, and/or physical activity, incorporating various BCTT domains, most commonly shaping knowledge, repetition and substitution, and goals and planning. However, there did not seem to be any observable differences between fatigue-targeted and non-fatigue-targeted interventions. Overall study quality was mixed, particularly in relation to power and outcome measures.
There are several promising nonpharmacological interventions for adolescent fatigue, although further work is needed to determine effectiveness. Future trials need to ensure design rigour, focusing on adequate powering, validated outcome measures, and adhering to best practice reporting guidelines.
•Evaluated how well nonpharmacological interventions reduce adolescent fatigue.•16 trials included, predominantly on CBT, physical activity, and psychoeducation.•No type of intervention consistently demonstrated promise across trials.•Mixed study quality reflects issues with blinding, power, and measurement.•Further work and innovation needed to refine intervention and trial design.
Many nanoparticles in fields such as heterogeneous catalysis undergo surface structural fluctuations during chemical reactions, which may control functionality. These dynamic structural changes may ...be ideally investigated with time-resolved in situ electron microscopy. We have explored approaches for extracting quantitative information from large time-resolved image data sets with a low signal to noise recorded with a direct electron detector on an aberration-corrected transmission electron microscope. We focus on quantitatively characterizing beam-induced dynamic structural rearrangements taking place on the surface of CeO2 (ceria). A 2D Gaussian fitting procedure is employed to determine the position and occupancy of each atomic column in the nanoparticle with a temporal resolution of 2.5 ms and a spatial precision of 0.25 Å. Local rapid lattice expansions/contractions and atomic migration were revealed to occur on the (100) surface, whereas (111) surfaces were relatively stable throughout the experiment. The application of this methodology to other materials will provide new insights into the behavior of nanoparticle surface reconstructions that were previously inaccessible using other methods, which will have important consequences for the understanding of dynamic structure-property relationships.
A secondary analysis of the COBRA randomized controlled trial was conducted to examine how well Cognitive Behavioural Therapy (CBT) and Behavioural Activation (BA) repair anhedonia. Patients with ...current major depressive disorder (N = 440) were randomized to receive BA or CBT, and anhedonia and depression outcomes were measured after acute treatment (six months) and at two further follow up intervals (12 and 18 months). Anhedonia was assessed using the Snaith Hamilton Pleasure Scale (SHAPS; a measure of consummatory pleasure). Both CBT and BA led to significant improvements in anhedonia during acute treatment, with no significant difference between treatments. Participants remained above healthy population averages of anhedonia at six months, and there was no further significant improvement in anhedonia at 12-month or 18-month follow up. Greater baseline anhedonia severity predicted reduced repair of depression symptoms and fewer depression-free days across the follow-up period in both the BA and CBT arms. The extent of anhedonia repair was less marked than the extent of depression repair across both treatment arms. These findings demonstrate that CBT and BA are similarly and only partially effective in treating anhedonia. Therefore, both therapies should be further refined or novel treatments should be developed in order better to treat anhedonia.
•A Secondary analysis of the COBRA RCT was conducted.•We examined how well CBT and BA for depression repair anhedonic symptoms.•CBT and BA were equally and sub-optimally effective at repairing anhedonia.•Greater anhedonic symptoms at intake predicted worse depression outcomes.•Anhedonia repair was less complete than depression repair.
The way individuals appraise positive emotions may modulate affective experience during positive activity scheduling. Individuals may either engage in dampening appraisals (e.g., think “this is too ...good to last”) or amplifying appraisals (e.g., think “I deserve this”). A cross-over randomized design was used to examine the consequences of these appraisal styles. Participants (N = 43) rated positive affect (PA) and negative affect (NA) during four daily walks in pleasant locations, whilst following dampening, emotion-focus amplifying (focusing on how good one feels), self-focus amplifying (focusing on positive self qualities), or control instructions. There was no difference between the two amplifying and control conditions, which all increased PA and reduced NA during the walks. However, the dampening condition significantly differed from all other conditions, reducing PA and increasing NA during the walk. Individual differences in anhedonia symptoms did not significantly moderate the pattern of findings. This evidence supports the view that dampening appraisals may be one mechanism driving anhedonia and may account for why positive activity scheduling can sometimes backfire when utilized in the clinic.
•Positive appraisal style was manipulated during positive activity scheduling.•Dampening appraisals led to decreases in positive, and increases in negative, affect.•Dampening appraisals may therefore account for why activity scheduling can backfire.
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