Reward functioning in PTSD: a systematic review exploring the mechanisms underlying anhedonia

Examining the Factor Structure of the Posttraumatic Checklist for Civilians

The Posttraumatic Checklist for Civilians (PCL-C) is one of the most common tools used to assess PTSD among civilian populations. However, the underlying factor structure of the PCL-C remains under examined, with the most recent research relying on small samples with limited generalizability. Thus, the present study used exploratory and confirmatory techniques in a large North American college student sample to investigate the factor structure of the PCL-C. Results supported a 3-factor model for the PCL-C accounting for 59% of the total variance and represented by Suppression (M = 11.2, SD = 5.0); Hyperarousal (M = 6.5, SD = 3.2); and Diminished Reward Processing (M = 5.9, SD = 2.9). Regarding gender differences, females tended to score higher on suppression and avoidance related symptoms, while males scored higher on symptoms related to Diminished Reward Processing. Results also showed that embedded within college campuses are trauma exposed students experiencing distressingly high levels of posttrauma symptoms. In sum, the results revealed three factors in the PCL-C, that could be used to offer insight into assessing and treating posttrauma symptoms on a college campus.

Neighborhood Resources Associated With Psychological Trajectories and Neural Reactivity to Reward After Trauma

Importance

Research on resilience after trauma has often focused on individual-level factors (eg, ability to cope with adversity) and overlooked influential neighborhood-level factors that may help mitigate the development of posttraumatic stress disorder (PTSD).

Objective

To investigate whether an interaction between residential greenspace and self-reported individual resources was associated with a resilient PTSD trajectory (ie, low/no symptoms) and to test if the association between greenspace and PTSD trajectory was mediated by neural reactivity to reward.

Design, Setting, and Participants

As part of a longitudinal cohort study, trauma survivors were recruited from emergency departments across the US. Two weeks after trauma, a subset of participants underwent functional magnetic resonance imaging during a monetary reward task. Study data were analyzed from January to November 2023.

Exposures

Residential greenspace within a 100-m buffer of each participant's home address was derived from satellite imagery and quantified using the Normalized Difference Vegetation Index and perceived individual resources measured by the Connor-Davidson Resilience Scale (CD-RISC).

Main Outcome and Measures

PTSD symptom severity measured at 2 weeks, 8 weeks, 3 months, and 6 months after trauma. Neural responses to monetary reward in reward-related regions (ie, amygdala, nucleus accumbens, orbitofrontal cortex) was a secondary outcome. Covariates included both geocoded (eg, area deprivation index) and self-reported characteristics (eg, childhood maltreatment, income).

Results

In 2597 trauma survivors (mean [SD] age, 36.5 [13.4] years; 1637 female [63%]; 1304 non-Hispanic Black [50.2%], 289 Hispanic [11.1%], 901 non-Hispanic White [34.7%], 93 non-Hispanic other race [3.6%], and 10 missing/unreported [0.4%]), 6 PTSD trajectories (resilient, nonremitting high, nonremitting moderate, slow recovery, rapid recovery, delayed) were identified through latent-class mixed-effect modeling. Multinominal logistic regressions revealed that for individuals with higher CD-RISC scores, greenspace was associated with a greater likelihood of assignment in a resilient trajectory compared with nonremitting high (Wald z test = -3.92; P < .001), nonremitting moderate (Wald z test = -2.24; P = .03), or slow recovery (Wald z test = -2.27; P = .02) classes. Greenspace was also associated with greater neural reactivity to reward in the amygdala (n = 288; t277 = 2.83; adjusted P value = 0.02); however, reward reactivity did not differ by PTSD trajectory.

Conclusions and Relevance

In this cohort study, greenspace and self-reported individual resources were significantly associated with PTSD trajectories. These findings suggest that factors at multiple ecological levels may contribute to the likelihood of resiliency to PTSD after trauma.

Sensorimotor Feedback Control Dysfunction as a Marker of Posttraumatic Stress Disorder

BACKGROUND

Posttraumatic stress disorder (PTSD) is characterized not only by its direct association with traumatic events but also by a potential deficit in inhibitory control across emotional, cognitive, and sensorimotor domains. Recent research has shown that a continuous sensorimotor feedback control task, the rapid assessment of motor processing (RAMP) paradigm, can yield reliable measures of individual sensorimotor control performance. This study used this paradigm to investigate control deficits in PTSD relative to both healthy volunteer and a non-PTSD psychiatric comparison group.

METHODS

We examined control processing using the RAMP paradigm in a sample of 40 individuals with PTSD, along with matched groups of 40 individuals with mood and anxiety (MA) complaints and 40 healthy controls (HC). We estimated Kp (drive) and Kd (damping) parameters using a proportion-derivative (PD) control modeling approach.

RESULTS

The Kp parameter was lower in the PTSD group compared to the HC (Cohen's d = .86) and MA groups (Cohen's d = 0.63). After controlling for color-word inhibition, Kp remained lower in the PTSD group versus HC (Cohen's d = 0.79) and versus MA (Cohen's d = 0.62). Mediation analysis showed that Kd significantly mediated the relationship between PTSD and control deficits in the Kp parameter, with 96% of the effect mediated by Kd.

CONCLUSIONS

These findings underscore the potential of using dynamic control paradigms to elucidate the control dysfunctions in PTSD and suggests that different psychiatric conditions may distinctly influence subcomponents of sensorimotor control.

A Functional Magnetic Resonance Imaging Meta-Analysis of Childhood Trauma

BACKGROUND

Traumatic experiences during childhood significantly impact the developing brain and contribute to the development of numerous physical and mental health problems. To date, however, a comprehensive understanding of the functional impairments within the brain associated with childhood trauma histories does not exist. Previous functional magnetic resonance imaging (fMRI) meta-analytical tools required homogeneity of task types and the clinical populations studied, thus preventing the comprehensive pooling of brain-based deficits present in children who have trauma histories. We hypothesized that the use of the novel, data-driven Bayesian author-topic model approach to fMRI meta-analyses would reveal deficits in brain networks that span fMRI task types in children with trauma histories.

METHODS

To our knowledge, this is the first study to use the Bayesian author-topic model approach to fMRI meta-analyses within a clinical population. Using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, we present data-driven results obtained by combining activation patterns across heterogeneous tasks from 1428 initially screened studies and combining data from 14 studies that met study criteria (285 children with trauma histories, 297 healthy control children).

RESULTS

Altered brain activity was revealed within 2 clusters in children with trauma histories compared to control children: the default mode/affective network/posterior insula and the central executive network. Our identified clusters were associated with tasks pertaining to cognitive processing, emotional/social stress, self-referential thought, memory, unexpected stimuli, and avoidance behaviors in youths who have experienced childhood trauma.

CONCLUSIONS

Our results reveal disturbances in children with trauma histories within the modulation of the default mode and central executive networks-but not the salience network-regardless of whether children also presented with posttraumatic stress symptoms.

Associations between transdiagnostic traits of psychopathology and hybrid posttraumatic stress disorder factors in a trauma-exposed community sample

Dimensional conceptualizations of psychopathology hold promise for understanding the high rates of comorbidity with posttraumatic stress disorder (PTSD). Linking PTSD symptoms to transdiagnostic dimensions of psychopathology may enable researchers and clinicians to understand the patterns and breadth of behavioral sequelae following traumatic experiences that may be shared with other psychiatric disorders. To explore this premise, we recruited a trauma-exposed online community sample (N = 462) and measured dimensional transdiagnostic traits of psychopathology using parceled facets derived from the Personality Inventory for DSM-5 Faceted-Short Form. PTSD symptom factors were measured using the PTSD Checklist for DSM-5 and derived using confirmatory factor analysis according to the seven-factor hybrid model (i.e., Intrusions, Avoidance, Negative Affect, Anhedonia, Externalizing Behaviors, Anxious Arousal, And Dysphoric Arousal). We observed hypothesized associations between PTSD factors and transdiagnostic traits indicating that some transdiagnostic dimensions were associated with nearly all PTSD symptom factors (e.g., emotional lability: rmean = .35), whereas others showed more unique relationships (e.g., hostility-Externalizing Behavior: r = .60; hostility with other PTSD factors: rs = .12-.31). All PTSD factors were correlated with traits beyond those that would appear to be construct-relevant, suggesting the possibility of indirect associations that should be explicated in future research. The results indicate the breadth of trait-like consequences associated with PTSD symptom exacerbation, with implications for case conceptualization and treatment planning. Although PTSD is not a personality disorder, the findings indicate that increased PTSD factor severity is moderately associated with different patterns of trait-like disruptions in many areas of functioning.

Out of touch? How trauma shapes the experience of social touch - Neural and endocrine pathways

Trauma can shape the way an individual experiences the world and interacts with other people. Touch is a key component of social interactions, but surprisingly little is known about how trauma exposure influences the processing of social touch. In this review, we examine possible neurobiological pathways through which trauma can influence touch processing and lead to touch aversion and avoidance in trauma-exposed individuals. Emerging evidence indicates that trauma may affect sensory touch thresholds by modulating activity in the primary sensory cortex and posterior insula. Disturbances in multisensory integration and oxytocin reactivity combined with diminished reward-related and anxiolytic responses may induce a bias towards negative appraisal of touch contexts. Furthermore, hippocampus deactivation during social touch may reflect a dissociative state. These changes depend not only on the type and severity of the trauma but also on the features of the touch. We hypothesise that disrupted touch processing may impair social interactions and confer elevated risk for future stress-related disorders.

Positive and negative affect change following psychotherapeutic treatment for anxiety-related disorders: A systematic review and meta-analysis

BACKGROUND

Anxiety-related disorders feature elevated negative affect (NA), and in some cases, diminished positive affect (PA). It remains unclear how well extant psychotherapies for anxiety-related disorders improve PA versus NA.

METHODS

We systematically searched the Cochrane Central Register of Controlled Trials, PubMed, PsychInfo, and Web of Science databases. Records included studies involving (1) patients with a principal or co-principal diagnosis of at least one anxiety-related disorder (i.e., generalized anxiety, social anxiety, panic, agoraphobia, health anxiety, specific phobia, obsessive-compulsive disorder, or posttraumatic stress disorder), and (2) pre- and post-treatment PA and NA scores or a change index between pre- and post-treatment PA and NA scores. Effect sizes were calculated for meta-analyses.

RESULTS

Fourteen studies with 1001 adults with an anxiety-related disorder were included. Psychotherapeutic interventions included cognitive behavioral, present-centered, and imagery-based approaches. Treatments reduced NA (g = -0.90; 95%CI [-1.19, -0.61]) to a greater extent than they improved PA (g = 0.27; 95%CI [0.05, 0.59]), Z = -5.26, p < .001. The limited number of studies available precluded analyses of the relationship between changes in affect and symptoms.

LIMITATIONS

Results should be considered with caution given the small number and heterogeneity of included studies.

CONCLUSIONS

Current psychotherapeutic interventions for anxiety-related disorders may not improve PA and NA to comparable levels.

Amplification of Positivity Treatment for Anxiety and Depression: A Randomized Experimental Therapeutics Trial Targeting Social Reward Sensitivity to Enhance Social Connectedness

BACKGROUND

Social disconnection is common and causes significant impairment in anxiety and depressive disorders, and it does not respond sufficiently to available treatments. The positive valence system supports social bond formation and maintenance but is often hyporesponsive in people with anxiety or depression. We conducted an experimental therapeutics trial to test the hypothesis that targeting positive valence processes through cognitive and behavioral strategies would enhance responsivity to social rewards, a core mechanism underlying social connectedness.

METHODS

Sixty-eight adults who endorsed clinically elevated anxiety and/or depression with social impairment were randomized 1:1:1 to 5 (n = 23) or 10 (n = 22) sessions of amplification of positivity (AMP) treatment or waitlist (n = 23). Pre- to posttreatment change in striatal activity (primary outcome) during social reward anticipation was measured using functional magnetic resonance imaging, and reactivity to a social affiliation task (secondary) and self-reported social connectedness (exploratory) were examined. Primary analyses compared AMP (doses combined) versus waitlist. A second aim was to compare the effects of different doses.

RESULTS

AMP engaged the hypothesized treatment target, leading to greater striatal activation during anticipation of social rewards versus waitlist (d = 1.01 [95% CI = 0.42-1.61]; largest striatal volume). AMP yielded larger improvements in positive affect and approach behavior during the affiliation task (but not other outcomes) and social connectedness. Larger striatal and social connectedness increases were observed for 5-session versus 10-session AMP (d range = 0.08-1.03).

CONCLUSIONS

Teaching people with anxiety or depression strategies to increase positive thoughts, behaviors, and emotions enhances activity in brain regions that govern social reward processing and promotes social connectedness. Social reward sensitivity may be a transdiagnostic target for remediating social disconnection.

MDMA enhances positive affective responses to social feedback

BACKGROUND

The prosocial compound ± 3,4-methylenedioxymethamphetamine (MDMA) is an amphetamine derivative that has shown promise as an adjunct to psychotherapy in the treatment of post-traumatic stress disorder. MDMA increases positive responses to social images, and it has been suggested that the ability of MDMA to positively bias social perception may underlie its therapeutic efficacy as a psychotherapy adjunct. However, the effect of the compound on affective responses to positive or negative social feedback has not been tested.

AIMS

In this study, we aimed to test the effects of MDMA compared to placebo and the prototypical stimulant, methamphetamine (MA), on responses to positive and negative social feedback.

METHODS

This was a double-blind, placebo-controlled, crossover trial (NCT03790618), comparing the effects of two doses of MDMA (0.75 mg/kg, 1.5 mg/kg) to both placebo and MA (20 mg) on responses to a personalized social feedback task, similar to a dating app, in healthy adult volunteers ages 18-40 (N = 36, 18 women, 18 men).

RESULTS/OUTCOMES

The high dose of MDMA increased positive affective responses to social feedback.

CONCLUSIONS/INTERPRETATIONS

These findings suggest one process by which MDMA may facilitate social connection. Further work is needed to understand how MDMA affects responses to more generalized types of social feedback and to understand these effects in clinical populations.

Social Anhedonia Accounts for Greater Variance in Internalizing Symptoms than Autism Symptoms in Autistic and Non-Autistic Youth

PURPOSE

Social anhedonia is a transdiagnostic trait that reflects reduced pleasure from social interaction. It has historically been associated with autism, however, very few studies have directly examined behavioral symptoms of social anhedonia in autistic youth. We investigated rates of social anhedonia in autistic compared to non-autistic youth and the relative contributions of autism and social anhedonia symptoms to co-occurring mental health.

METHODS

Participants were 290 youth (Mage=13.75, Nautistic=155) ranging in age from 8 to 18. Youth completed a cognitive assessment and a diagnostic interview. Their caregiver completed questionnaires regarding symptoms of autism and co-occurring psychiatric conditions.

RESULTS

Autistic youth were more likely to meet criteria for social anhedonia than non-autistic youth. There was a significant positive relationship between age and social anhedonia symptom severity, but there was no association between sex and social anhedonia. Dominance analysis revealed that social anhedonia symptom severity had the strongest association with symptoms of depression and social anxiety, while symptoms of ADHD, generalized anxiety, and separation anxiety were most strongly associated with autism symptom severity.

CONCLUSION

This was the first study to tease out the relative importance of social anhedonia and autism symptoms in understanding psychiatric symptoms in autistic youth. Findings revealed higher rates of social anhedonia in autistic youth. Our results indicate that social anhedonia is an important transdiagnostic trait that plays a unique role in understanding co-occurring depression and social anxiety in autistic youth. Future research should utilize longitudinal data to test the transactional relationships between social anhedonia and internalizing symptoms over time.

Latent-state and model-based learning in PTSD

Post-traumatic stress disorder (PTSD) is characterized by altered emotional and behavioral responding following a traumatic event. In this article, we review the concepts of latent-state and model-based learning (i.e., learning and inferring abstract task representations) and discuss their relevance for clinical and neuroscience models of PTSD. Recent data demonstrate evidence for brain and behavioral biases in these learning processes in PTSD. These new data potentially recast excessive fear towards trauma cues as a problem in learning and updating abstract task representations, as opposed to traditional conceptualizations focused on stimulus-specific learning. Biases in latent-state and model-based learning may also be a common mechanism targeted in common therapies for PTSD. We highlight key knowledge gaps that need to be addressed to further elaborate how latent-state learning and its associated neurocircuitry mechanisms function in PTSD and how to optimize treatments to target these processes.

Anhedonia mediates the relationships between childhood trauma and symptom severity of PTSD and depression, but not of social anxiety

BACKGROUND

Childhood trauma is a risk factor for developing multiple forms of psychopathology, including depression, posttraumatic stress disorder (PTSD), and social anxiety. Yet, the mechanisms linking childhood trauma and these psychopathologies remain less clear.

OBJECTIVE

Here we examined whether anhedonia, a reduced ability to experience pleasure, may mediate the relationship between childhood trauma and symptom severity of depression, PTSD, and social anxiety.

METHODS

A total of 230 trauma-exposed participants aged 18-75 were assessed for lifetime trauma exposure, including general and childhood traumatic events, anhedonia, and symptoms of depression, PTSD, and social anxiety.

RESULTS

Controlling for age, gender, and general lifetime trauma exposure, mediation analyses revealed a significant mediation effect of anhedonia for the relationship between childhood trauma and symptom severity of depression and PTSD, but not social anxiety. To better understand these significant mediation effects, we repeated the analyses separately for childhood abuse and neglect, and then for the various subtypes of each type of childhood trauma. Results showed a significant mediation effect of anhedonia on symptoms of both depression and PTSD in individuals who reported high emotional and sexual abuse levels. F Anhedonia was also found to mediate the relationship between both emotional and physical neglect and symptoms of depression and PTSD.

CONCLUSION

These findings refine our understanding of the ways in which childhood traumatic experiences may be associated with different mental health problems by increasing anhedonia. Anhedonia may be an important treatment target in survivors of childhood abuse and neglect.

Anhedonia and Delay Discounting: Differing Patterns of Brain-Behavior Relationships in Healthy Control Participants Versus Individuals With Posttraumatic Stress Disorder

BACKGROUND

Anhedonia may contribute to individual differences in delay discounting (DD). In prior work, we found that higher anhedonia was associated with shallower DD in healthy control (HC) participants but steeper DD in individuals with posttraumatic stress disorder (PTSD). In this study, we aimed to directly compare the relationship between anhedonia and DD across groups and to identify functional brain correlates of this interaction.

METHODS

Participants (HC group: n = 23, DSM-5 PTSD group: n = 23) completed a questionnaire assessing anhedonia (Snaith-Hamilton Pleasure Scale [SHAPS]), task-based functional magnetic resonance imaging of decision making including DD, and resting-state functional magnetic resonance imaging. Task-based activity and resting-state functional connectivity were evaluated in reward-related regions that have also been implicated in PTSD (nucleus accumbens [NAcc], right anterior insula).

RESULTS

Higher SHAPS scores were associated with steeper DD in PTSD, but there was no relationship between DD and SHAPS in the HC group. There was a significant group-by-SHAPS interaction for NAcc activity, t31 = 2.92, p = .007: Greater NAcc activity when immediate rewards were chosen was associated with higher SHAPS in the PTSD group but lower SHAPS in the HC group. In resting-state functional connectivity, there was a group-by-SHAPS interaction between the NAcc seed and right parietal and frontal pole clusters.

CONCLUSIONS

These results extend prior findings that anhedonia is associated with steeper DD in PTSD and demonstrate that this behavioral finding occurs in the context of NAcc hyperactivity to immediate rewards and hyperconnectivity in anhedonic individuals with PTSD.

Personality characteristics, not clinical symptoms, are associated with anhedonia in a community sample: A preliminary investigation

Anhedonia is a salient transdiagnostic psychiatric symptom associated with increased illness severity and chronicity. Anhedonia is also present to varying degrees in non-clinical cohorts. Here, we sought to examine factors influencing expression of anhedonia. Participants (N = 335) were recruited through the Nathan Kline Institute-Rockland Sample, an initiative to deeply phenotype a large community sample across the lifespan. Utilizing a data-driven approach, we evaluated associations between anhedonia severity, indexed by Snaith-Hamilton Pleasure Scale (SHAPS), and 20 physical, developmental, and clinical measures, including Structured Clinical Interview for DSM-IV, Beck Depression Inventory, State-Trait Anxiety Inventory, NEO Five-Factor Inventory-3 (NEO-FFI-3), BMI, Hemoglobin A1C, and demography. Using a bootstrapped AIC-based backward selection algorithm, seven variables were retained in the final model: NEO-FFI-3 agreeableness, extraversion, and openness to experience; BMI; sex; ethnicity; and race. Though median SHAPS scores were greater in participants with psychiatric diagnoses (18.5) than those without (17.0) (U = 12238.5, z = 2.473, p = 0.013), diagnosis and symptom measures were not retained as significant predictors in the final robust linear model. Participants scoring higher on agreeableness, extraversion, and openness to experience reported significantly lower anhedonia. These results demonstrate personality as a mild-to-moderate but significant driver of differences in experiencing pleasure in a community sample.

Rethinking Research on Prediction and Prevention of Psychotherapy Dropout: A Mechanism-Oriented Approach

Dropout is a ubiquitous psychotherapy outcome in clinical practice and treatment research alike, yet it remains a poorly understood problem. Contemporary dropout research is dominated by models of prediction that lack a strong theoretical foundation, often drawing on data from clinical trials that report on dropout in an inconsistent and incomplete fashion. In this article, we assert that dropout is a critical treatment outcome that is worthy of investigation as a mechanistic process. After briefly describing the scope of the dropout problem, we discuss the many factors that limit the field's present understanding of dropout. We then articulate and illustrate a transdiagnostic conceptual framework for examining psychotherapy dropout in contemporary research, concluding with recommendations for future research. With a more comprehensive understanding of the factors affecting retention, research efforts can shift toward investigating key processes underlying treatment dropout, thus, boosting prediction and informing strategies to mitigate dropout in clinical practice.

Event-level positive and negative reinforcement risk factors for alcohol use: Moderation by individual-level alcohol consequences and post-traumatic stress disorder symptom severity

BACKGROUND

The multistage model of drug addiction posits that risk processes contributing to alcohol use change as individuals develop alcohol use disorders. However, few studies have tested this theory outside of the lab or at the event level. We assessed whether event-level associations between positive reinforcement (e.g., positive affect, sociability expectancies) and negative reinforcement risk factors (e.g., negative affect, tension reduction expectancies) and same-/next-day alcohol consumption varied as a function of an individual's level of alcohol consequences. Given elevated alcohol use consequences among individuals with post-traumatic stress disorder (PTSD) and disruptions in reward processing that affect this population, we also tested whether these processes differed based on the presence and severity of PTSD.

METHODS

We used data from a 30-day ecological momentary assessment study with 174 undergraduate women who regularly engaged in heavy episodic drinking. A majority (78%) of the sample had experienced sexual assault and 44% had current PTSD. Analyses used Bayesian multilevel structural equation modeling with diffuse (non-informative) priors. We used markov chain monte carlo (MCMC) algorithms to generate a series of 10,000 random draws from the multivariate posterior distribution of our sample for each model.

RESULTS

Results partially supported the multistage model. Event-level negative reinforcement risk factors only predicted more alcohol consumption among individuals who experienced more alcohol consequences. Findings for positive reinforcement risk factors were partially consistent with hypotheses. Overall, findings appear to operate similarly across PTSD symptom severity.

CONCLUSIONS

Results suggest that interventions for heavy episodic drinking could benefit from attending to an individual's level of alcohol consequences. For example, preventive interventions for individuals who tend to experience few consequences may benefit more from addressing positive reinforcement risk factors, while treatment interventions for those who experience more consequences may benefit from attending to both positive and negative reinforcement.

Using latent profile analyses to classify subjects with anhedonia based on reward-related measures obtained in the FAST-MAS study

BACKGROUND

Growing evidence indicates that anhedonia is a multifaceted construct. This study examined the possibility of identifying subgroups of people with anhedonia using multiple reward-related measures to provide greater understanding the Research Domain Criteria's Positive Valence Systems Domain and pathways for developing treatments.

METHODS

Latent profile analysis of baseline data from a study that examined the effects of a novel kappa opioid receptor (KOR) antagonist drug on measures and biomarkers associated with anhedonia was used to identify subgroups. Measures included ventral striatal activation during the Monetary Incentive Delay task, response bias in the Probabilistic Reward Task, reward valuation scores from the Effort-Expenditure for Rewards Task, and scores from reward-related self-report measures.

RESULTS

Two subgroups were identified, which differed on self-report measures of reward. Participants in the subgroup reporting more anhedonia also reported more depression and had greater illness severity and functional impairments. Graphs of change with treatment showed a trend for the less severe subgroup to demonstrate higher response to KOR antagonist treatment on the neuroimaging measure, probabilistic reward task, and ratings of functioning; the subgroup with greater severity showed a trend for higher treatment response on reward-related self-report measures.

LIMITATIONS

The main limitations include the small sample size and exploratory nature of analyses.

CONCLUSIONS

Evidence of possible dissociation between self-reported measures of anhedonia and other measures with respect to treatment response emerged. These results highlight the importance for future research to consider severity of self-reported reward-related deficits and how the relationship across measurement methods may vary with severity.

Psychological and physiological correlates of stimulus discrimination in adults

The discrimination of cues in the environment that signal danger ("fear cue") is important for survival but depends critically on the discernment of such cues from ones that pose no threat ("safety cues"). In rodents, we previously demonstrated the underlying neurobiological mechanisms that support fear versus safety discrimination and documented that these mechanisms extend to the discrimination of reward as well. While learning about reward is equally important for survival, it remains an under-studied area of research, particularly in human studies of conditional discrimination. In the present study, we translated our rodent task of fear reward and neutral discrimination (fear, reward, and neutral discrimination [FRND]) for use in humans. Undergraduate students (N = 53) completed the FRND while electrodermal activity was recorded. Skin conductance response (SCR) amplitude, a marker of arousal response, was derived for fear, reward, and neutral cues that signaled no outcome; critical trials assessed conditional discrimination using combined fear + neutral and reward + neutral cues. Participants provided likeability ratings for each cue type. Results demonstrated that participants rated reward cues the best, fear cues the worst, and neutral cues in between, while SCR amplitude was largest for fear and reward cues and lowest for neutral cues. SCR amplitudes were reduced for fear + neutral (compared to fear) and reward + neutral cues (compared to reward). Results demonstrate that the FRND is a useful paradigm for the assessment of psychological and physiological discrimination of fear and reward. Implications and directions for future work are discussed.

Role of the intraparietal sulcus (IPS) in anxiety and cognition: Opportunities for intervention for anxiety-related disorders

Our objective was to review the literature on the parietal cortex and intraparietal sulcus (IPS) in anxiety-related disorders, as well as opportunities for using neuromodulation to target this region and reduce anxiety. We provide an overview of prior research demonstrating: 1) the importance of the IPS in attention, vigilance, and anxious arousal, 2) the potential for neuromodulation of the IPS to reduce unnecessary attention toward threat and anxious arousal as demonstrated in healthy samples; and 3) limited data on the potential for neuromodulation of the IPS to reduce hyper-attention toward threat and anxious arousal among clinical samples with anxiety-related disorders. Future research should evaluate the efficacy of IPS neuromodulation in fully powered clinical trials, as well as the value in augmenting evidence-based treatments for anxiety with IPS neuromodulation.

Pharmacological activation of the amygdala, but not single prolonged footshock-induced acute stress, interferes with cue-induced motivation toward food rewards in rats

In the face of threats, animals adapt their behaviors to cope with the situation. Under such circumstances, irrelevant behaviors are usually suppressed. In this study, we examined whether food-seeking motivation would decrease under activation of the amygdala, an important nucleus in the regulation of stress response in the central nervous system, or after a physical acute stress session. In Experiment 1, we pharmacologically activated the basolateral nucleus (BLA) or the central nucleus of the amygdala (CeA) before a cue-induced reinstatement test in rats. Our results showed that activation of the BLA or the CeA abolished cue-induced motivation toward food rewards, while locomotor activity and free food intake were not affected. In Experiments 2 and 3, we further assessed anxiety and despair levels, as well as cue-induced reinstatement, after a single prolonged footshock-induced acute stress in rats. Behaviorally, acute stress did not affect anxiety level, despair level, or cue-induced motivation toward food rewards. Physiologically, there was no difference in cellular activities of the amygdala immediately after acute stress. To conclude, our results suggested that pharmacological activation of the amygdala decreased cue-induced motivation toward food reward. However, physiological acute stress did not immediately interfere with the negative emotions, motivation, or amygdala activities of the animals.

Neighborhood Disadvantage and Neural Correlates of Threat and Reward Processing in Survivors of Recent Trauma

Importance

Differences in neighborhood socioeconomic characteristics are important considerations in understanding differences in risk vs resilience in mental health. Neighborhood disadvantage is associated with alterations in the function and structure of threat neurocircuitry.

Objective

To investigate associations of neighborhood disadvantage with white and gray matter and neural reactivity to positive and negative stimuli in the context of trauma exposure.

Design, Setting, and Participants

In this cross-sectional study, survivors of trauma who completed sociodemographic and posttraumatic symptom assessments and neuroimaging were recruited as part of the Advancing Understanding of Recovery After Trauma (AURORA) study between September 2017 and June 2021. Data analysis was performed from October 25, 2022, to February 15, 2023.

Exposure

Neighborhood disadvantage was measured with the Area Deprivation Index (ADI) for each participant home address.

Main Outcomes and Measures

Participants completed separate threat and reward tasks during functional magnetic resonance imaging. Diffusion-weighted and high-resolution structural images were also collected. Linear models assessed the association of ADI with reactivity, microstructure, and macrostructure of a priori regions of interest after adjusting for income, lifetime trauma, sex at birth, and age. A moderated-mediation model tested whether ADI was associated with neural activity via microstructural changes and if this was modulated by PTSD symptoms.

Results

A total of 280 participants (183 females [65.4%]; mean [SD] age, 35.39 [13.29] years) completed the threat task and 244 participants (156 females [63.9%]; mean [SD] age, 35.10 [13.26] years) completed the reward task. Higher ADI (per 1-unit increase) was associated with greater insula (t274 = 3.20; β = 0.20; corrected P = .008) and anterior cingulate cortex (ACC; t274 = 2.56; β = 0.16; corrected P = .04) threat-related activity after considering covariates, but ADI was not associated with reward reactivity. Greater disadvantage was also associated with altered microstructure of the cingulum bundle (t274 = 3.48; β = 0.21; corrected P = .001) and gray matter morphology of the ACC (cortical thickness: t273 = -2.29; β = -0.13; corrected P = .02; surface area: t273 = 2.53; β = 0.13; corrected P = .02). The moderated-mediation model revealed that ADI was associated with ACC threat reactivity via cingulum microstructural changes (index of moderated mediation = -0.02). However, this mediation was only present in individuals with greater PTSD symptom severity (at the mean: β = -0.17; standard error = 0.06, t= -2.28; P = .007; at 1 SD above the mean: β = -0.28; standard error = 0.08; t = -3.35; P < .001).

Conclusions and Relevance

In this study, neighborhood disadvantage was associated with neurobiology that supports threat processing, revealing associations of neighborhood disadvantage with neural susceptibility for PTSD and suggesting how altered structure-function associations may complicate symptoms. Future work should investigate specific components of neighborhood disadvantage that may be associated with these outcomes.

Neural Correlates of Reward Processing in the Onset, Maintenance, and Treatment of Posttraumatic Stress Disorder

Posttraumatic stress disorder (PTSD) is a prevalent, debilitating, and heterogeneous psychiatric condition marked by both exaggerated threat responding and diminished positive affect. While symptom profiles of PTSD differ across individuals, symptoms also vary within individuals over the course of illness. Functional magnetic resonance imaging studies have provided crucial insights into the neurobiology of heightened threat responsivity in PTSD, which has aided in identifying neurobiological risk factors and treatment targets for this disorder. Despite this demonstrated utility, the application of functional magnetic resonance imaging to understanding deficits in reward responsivity in PTSD remains underexplored. Significantly, over 60% of individuals with PTSD experience anhedonia, or an inability to feel pleasure, which may reflect reward processing deficits. To better understand the neural underpinnings of reward deficits and their relevance to the onset, maintenance, and treatment of PTSD, we reviewed the functional magnetic resonance imaging literature through the framework of disease prognosis. Here, we provide insights on whether reward deficits are central to PTSD or are better explained by comorbid major depressive disorder, and we clarify how reward-related deficiencies in PTSD fit into the context of more intensely studied threat-related deficits.

Striatal dopamine in anhedonia: A simultaneous [11C]raclopride positron emission tomography and functional magnetic resonance imaging investigation

BACKGROUND

Anhedonia is hypothesized to be associated with blunted mesocorticolimbic dopamine (DA) functioning in samples with major depressive disorder. The purpose of this study was to examine linkages between striatal DA, reward circuitry functioning, anhedonia, and, in an exploratory fashion, self-reported stress, in a transdiagnostic anhedonic sample.

METHODS

Participants with (n = 25) and without (n = 12) clinically impairing anhedonia completed a reward-processing task during simultaneous positron emission tomography and magnetic resonance (PET-MR) imaging with [11C]raclopride, a DA D2/D3 receptor antagonist that selectively binds to striatal DA receptors.

RESULTS

Relative to controls, the anhedonia group exhibited decreased task-related DA release in the left putamen, caudate, and nucleus accumbens and right putamen and pallidum. There were no group differences in task-related brain activation (fMRI) during reward processing after correcting for multiple comparisons. General functional connectivity (GFC) findings revealed blunted fMRI connectivity between PET-derived striatal seeds and target regions in the anhedonia group. Associations were identified between anhedonia severity and the magnitude of task-related DA release to rewards in the left putamen, but not mesocorticolimbic GFC.

CONCLUSIONS

Results provide evidence for reduced striatal DA functioning during reward processing and blunted mesocorticolimbic network functional connectivity in a transdiagnostic sample with clinically significant anhedonia.

Reward Processing in Psychiatric Inpatients With Depression

BACKGROUND

Previous neuroimaging studies have investigated reward-processing dysfunction in major depressive disorder and have led to the common finding that major depressive disorder is associated with reduced reward responses within the reward circuit. Yet it is unclear whether such reward-processing dysfunction is specifically associated with the severity of depressive symptoms in major depressive disorder or is associated with common comorbidities.

METHODS

We investigated reward-processing differences using a classic juice-delivery functional magnetic resonance imaging experiment to compare psychiatric patients with severe depressive symptoms (DEPs) to both psychiatric control subjects (PCs) and healthy control subjects. In this study, the DEPs (n = 108) were matched to healthy control subjects (n = 62) for demographic characteristics and to the PCs (n = 108) for demographics and comorbid psychiatric diagnoses. An a priori region of interest, the left putamen, was selected using previous studies. An exploratory whole-brain analysis was performed to explore for nonhypothesized regions.

RESULTS

Relative to the PCs and healthy control subjects, the DEP group showed smaller responses to reward stimulus in the left putamen. Whole-brain exploratory analysis revealed that DEPs had significantly lower responses to reward stimulus in the bilateral dorsal striatum (putamen and caudate), middle frontal gyrus, left precentral gyrus, and middle cingulate cortex than PCs.

CONCLUSIONS

Our findings suggest that DEPs may have a lesser ability to modulate behavior as a function of reward, especially in those individuals who experience the most severe depressive symptoms. In both DEPs and PCs, the severity of depressive symptoms was related to reduced reward responses in the left putamen.

Brain Monoamine Dysfunction in Response to Predator Scent Stress Accompanies Stress-Susceptibility in Female Rats

Post-traumatic stress disorder (PTSD) is prevalent in women; however, preclinical research on PTSD has predominantly been conducted in male animals. Using a predator scent stress (PSS) rodent model of PTSD, we sought to determine if stress-susceptible female rats show altered monoamine concentrations in brain regions associated with PTSD: the medial prefrontal cortex (mPFC), nucleus accumbens (NAc), and dorsal (dHIPP) and ventral (vHIPP) hippocampus. Female Sprague-Dawley rats were exposed to a single, 10-min PSS exposure and tested for persistent anhedonia, fear, and anxiety-like behavior over four weeks. Rats were phenotyped as stress-Susceptible based on sucrose consumption in the sucrose preference task and time spent in the open arms of the elevated plus maze. Brain tissue was collected, and norepinephrine, dopamine, serotonin, and their metabolites were quantified using high-performance liquid chromatography. Stress-susceptibility in female rats was associated with increased dopamine and serotonin turnover in the mPFC. Susceptibility was also associated with elevated dopamine turnover in the NAc and increased norepinephrine in the vHIPP. Our findings suggest that stress-susceptibility after a single stress exposure is associated with long-term effects on monoamine function in female rats. These data suggest interventions that decrease monoamine turnover, such as MAOIs, may be effective in the treatment of PTSD in women.

Functional neuroimaging of resilience to trauma: convergent evidence and challenges for future research

Resilience is broadly defined as the ability to adapt successfully following stressful life events. Here, we review functional MRI studies that investigated key psychological factors that have been consistently linked to resilience to severe adversity and trauma exposure. These domains include emotion regulation (including cognitive reappraisal), reward responsivity, and cognitive control. Further, we briefly review functional imaging evidence related to emerging areas of study that may potentially facilitate resilience: namely social cognition, active coping, and successful fear extinction. Finally, we also touch upon ongoing issues in neuroimaging study design that will need to be addressed to enable us to harness insight from such studies to improve treatments for - or, ideally, guard against the development of - debilitating post-traumatic stress syndromes.

Quantifying aberrant approach-avoidance conflict in psychopathology: A review of computational approaches

Making effective decisions during approach-avoidance conflict is critical in daily life. Aberrant decision-making during approach-avoidance conflict is evident in a range of psychological disorders, including anxiety, depression, trauma-related disorders, substance use disorders, and alcohol use disorders. To help clarify etiological pathways and reveal novel intervention targets, clinical research into decision-making is increasingly adopting a computational psychopathology approach. This approach uses mathematical models that can identify specific decision-making related processes that are altered in mental health disorders. In our review, we highlight foundational approach-avoidance conflict research, followed by more in-depth discussion of computational approaches that have been used to model behavior in these tasks. Specifically, we describe the computational models that have been applied to approach-avoidance conflict (e.g., drift-diffusion, active inference, and reinforcement learning models), and provide resources to guide clinical researchers who may be interested in applying computational modeling. Finally, we identify notable gaps in the current literature and potential future directions for computational approaches aimed at identifying mechanisms of approach-avoidance conflict in psychopathology.

Positive emotion in posttraumatic stress disorder: A global or context-specific problem?

Problems with positive emotion are an important component of posttraumatic stress disorder (PTSD), with competing perspectives as to why. The global model suggests that people with PTSD experience a relatively permanent shift in their capacity for positive emotion regardless of context, whereas the context-specific model posits access to the full repertoire of positive emotion that only becomes reduced during exposure to trauma reminders. We tested the global versus context-specific models using ecological momentary assessment (EMA). Trauma-exposed adult community members (N = 80) with (n = 39) and without diagnosed PTSD completed 3 days of EMA (n = 2,158 observations). Participants with PTSD reported lower average momentary levels of positive emotion, B = -0.947, 95% CI [-1.35, -0.54], p < .001, and positive situations, B = -0.607, 95% CI [-1.16, -0.05], p = .032, and more thinking about trauma reminders, B = 0.360, 95% CI [0.21, 0.51], p < .001. There was no between-group difference in positive emotion reactivity (degree of positive emotion derived from positive situations), B = 0.03, 95% CI [-0.09, 0.14], p = .635. Increased thinking about trauma reminders predicted lower momentary levels of positive emotion, B = -0.55, 95% CI [-0.83, -0.26], p < .001, but not reactivity, B = 0.02, 95% CI [-0.35, 0.40], p = .906, irrespective of PTSD status. Findings supported the global model and were inconsistent with the context-specific model. This study helps clarify positive emotional functioning in trauma-exposed adults and highlights future directions to better understand problems with positive emotion in PTSD.

Neural valuation of rewards and punishments in posttraumatic stress disorder: a computational approach

Posttraumatic stress disorder (PTSD) is associated with changes in fear learning and decision-making, suggesting involvement of the brain's valuation system. Here we investigate the neural mechanisms of subjective valuation of rewards and punishments in combat veterans. In a functional MRI study, male combat veterans with a wide range of posttrauma symptoms (N = 48, Clinician Administered PTSD Scale, CAPS-IV) made a series of choices between sure and uncertain monetary gains and losses. Activity in the ventromedial prefrontal cortex (vmPFC) during valuation of uncertain options was associated with PTSD symptoms, an effect which was consistent for gains and losses, and specifically driven by numbing symptoms. In an exploratory analysis, computational modeling of choice behavior was used to estimate the subjective value of each option. The neural encoding of subjective value varied as a function of symptoms. Most notably, veterans with PTSD exhibited enhanced representations of the saliency of gains and losses in the neural valuation system, especially in ventral striatum. These results suggest a link between the valuation system and the development and maintenance of PTSD, and demonstrate the significance of studying reward and punishment processing within subject.

Your smile won't affect me: Association between childhood maternal antipathy and adult neural reward function in a transdiagnostic sample

Aberrant activation in the ventral striatum (VS) during reward anticipation may be a key mechanism linking adverse childhood experiences (ACE) to transdiagnostic psychopathology. This study aimed to elucidate whether retrospectively reported ACE, specifically maternal antipathy, relate to monetary and social reward anticipation in a transdiagnostic adult sample. A cross-sectional neuroimaging study was conducted in 118 participants with varying levels of ACE, including 25 participants with posttraumatic stress disorder (PTSD), 32 with major depressive disorder (MDD), 29 with somatic symptom disorder (SSD), and 32 healthy volunteers (HVs). Participants underwent functional magnetic resonance imaging during a monetary and social incentive delay task, and completed a self-report measure of ACE, including maternal antipathy. Neural correlates of monetary and social reward anticipation and their association with ACE, particularly maternal antipathy, were analyzed. Participants showed elevated activation in brain regions underlying reward processing, including the VS, only while anticipating social, but not monetary rewards. Participants reporting higher levels of maternal antipathy exhibited reduced activation in the brain reward network, including the VS, only during social, but not monetary reward anticipation. Group affiliation moderated the association between maternal antipathy and VS activation to social reward anticipation, with significant associations found in participants with PTSD and HVs, but not in those with MDD and SSD. Results were not associated with general psychopathology or psychotropic medication use. Childhood maternal antipathy may confer risk for aberrant social reward anticipation in adulthood, and may thus be considered in interventions targeting reward expectations from social interactions.

The anticipatory and consummatory interpersonal pleasure scale: Applicability to Chinese OCD patients

As a transdiagnostic symptom, social anhedonia has gained increasing attention. Evidence suggests that obsessive-compulsive disorder (OCD) patients demonstrate social anhedonia. This study examined the psychometric properties of the Anticipatory and Consummatory Interpersonal Pleasure Scale (ACIPS) in an undergraduate sample and Chinese OCD patients. Furthermore, we explored the relationship between clinical symptoms and ACIPS scores. This study involved 3,306 undergraduate students and 293 patients with OCD. Internal consistency and convergent validity of ACIPS were examined. Confirmatory factor analysis (CFA) was applied to determine the best-fitting of potential factor models, and multi-group CFA was used to examine measurement invariance across genders and samples. Additionally, hierarchical linear regression was conducted in order to investigate the relationship between clinical symptoms and ACIPS scores in patients suffering from OCD. ACIPS showed acceptable internal consistency in undergraduate and OCD samples (Cronbach's α = 0.93 and 0.89, respectively). In both samples, the four-factor structure had the best fit index. Scalar invariance was established across undergraduate and OCD samples, while residual invariance was established across genders. In both samples, the ACIPS was significantly correlated with the Revised Social Anhedonia Scale and Beck Depression Inventory. Depression and the severity of obsessive thoughts significantly and negatively correlated with the ACIPS score in OCD patients (p < 0.05). In conclusion, ACIPS is a reliable, effective, simple, and convenient tool for the assessment of social anhedonia. Depression and obsessive thoughts contribute to social anhedonia in OCD patients.

Associations between the late positive potential and PTSD, anxiety, and depressive symptoms among trauma-exposed undergraduates

BACKGROUND

The late positive potential (LPP) is a neural marker of attention to emotional stimuli; dysregulations in those attentional processes might contribute to trauma-related psychopathology. Although higher LPP amplitudes to negative images have been found to be associated with anxiety symptoms, results have been mixed regarding depressive and PTSD symptoms, especially among trauma-exposed populations. Further, the relationships between the LPP to positive and neutral images and psychopathology symptoms have been underexamined. The purpose of the current study was to test the effects of image valence, and PTSD, anxiety, and depressive symptoms on LPP amplitude among trauma-exposed undergraduates.

METHOD

Seventy-three trauma-exposed undergraduates viewed a series of negative, positive, and neutral images while LPPs were recorded. Self-report measures were used to assess recent PTSD, anxiety, and depressive symptoms. Hierarchical linear modeling tested valence and symptom main effects, as well as Valence by Symptom interactions on LPP amplitude.

RESULTS

We found a main effect of valence such that individuals exhibited higher LPP amplitudes to negative images compared to neutral images. We also found a Valence by Depressive Symptoms interaction such that there was an inverse relationship between depressive symptoms and the LPP to neutral images but no associations between depressive symptoms and the LPP for positive or negative images. We found no main effects or interactions for anxiety and PTSD symptoms.

CONCLUSION

Depressive symptoms might be related to diminished attention to neutral stimuli among trauma-exposed undergraduates. Further investigation of the relationship between the LPP and psychopathology is needed.

Effects of comorbid posttraumatic stress disorder on cognitive dysfunction in Chinese male methamphetamine patients

OBJECTIVES

Cognitive dysfunction and posttraumatic stress disorder (PTSD) are common in methamphetamine patients. However, few studies have investigated the cognitive performance of methamphetamine patients with PTSD. The purpose of this study was to investigate the impact of comorbid PTSD on cognitive function in Chinese male methamphetamine patients.

METHODS

We analyzed 464 methamphetamine patients and 156 healthy volunteers. The PTSD Screening Scale (PCL-5) was used to assess PTSD and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) was used to assess cognitive function.

RESULTS

Compared with healthy controls, methamphetamine patients had more cognitive dysfunction in immediate memory, visuospatial/constructional, language, attention and delayed memory. Moreover, methamphetamine patients with PTSD had less cognitive dysfunction in immediate memory, attention, and delayed memory than methamphetamine patients without PTSD. Further stepwise regression analysis showed that PTSD alterations in arousal and reactivity cluster were risk predictors for language, and PTSD negative alteration in cognition and mood cluster were risk predictors for delayed memory.

CONCLUSIONS

Our results indicate that methamphetamine patients without PTSD have poorer cognitive dysfunction than those with PTSD. Some demographic and PTSD symptom clusters are protective or risk factors for cognitive dysfunction in methamphetamine patients.

Individualized prediction of consummatory anhedonia from functional connectome in major depressive disorder

BACKGROUND

Anhedonia is a key symptom of major depressive disorder (MDD) and other psychiatric diseases. The neural basis of anhedonia has been widely examined, yet the interindividual variability in neuroimaging biomarkers underlying individual-specific symptom severity is not well understood.

METHODS

To establish an individualized prediction model of anhedonia, we applied connectome-based predictive modeling (CPM) to whole-brain resting-state functional connectivity profiles of MDD patients.

RESULTS

The CPM can successfully and reliably predict individual consummatory but not anticipatory anhedonia. The predictive model mainly included salience network (SN), frontoparietal network (FPN), default mode network (DMN), and motor network. Importantly, subsequent computational lesion prediction and consummatory-specific model prediction revealed that connectivity of the SN with DMN and FPN is essential and specific for the prediction of consummatory anhedonia.

CONCLUSIONS

This study shows that brain functional connectivity, especially the connectivity of SN-FPN and SN-DMN, can specifically predict individualized consummatory anhedonia in MDD. These findings suggest the potential of functional connectomes for the diagnosis and prognosis of anhedonia in MDD and other disorders.

Functional and structural brain abnormalities in posttraumatic stress disorder: A multimodal meta-analysis of neuroimaging studies

BACKGROUND

Numerous resting-state functional and structural studies have revealed that many brain regions are involved in the pathogenesis of posttraumatic stress disorder (PTSD), but their findings have been inconsistent. Moreover, there has no study explored the functional and structural alterations across languages in PTSD.

METHODS

A meta-analysis of whole-brain on the amplitude of low-frequency fluctuation (ALFF) and voxel-based morphometry (VBM) studies that explored alterations in the spontaneous functional brain activity and grey matter volume (GMV) in PTSD patients across languages by using the Seed-based d Mapping with Permutation of Subject Images (SDM-PSI) software.

RESULTS

A total of 15 studies (19 datasets) comprising 577 PTSD patients and 499 HCs for ALFF, and 27 studies (31 datasets) comprising 539 PTSD patients and 693 HCs for VBM were included. Overall, PTSD patients across languages displayed decreased ALFF in the in the left amygdala. For VBM meta-analysis, PTSD patients across languages displayed reduced GMV in the bilateral anterior cingulate cortex/medial prefrontal cortex (ACC/mPFC), striatum, insula, superior temporal gyrus, left postcentral gyrus, and occipital gyrus.

CONCLUSIONS

The multimodal meta-analysis suggest that PTSD patients showed similar pattern of aberrant resting-state functional brain activity and structure mainly in the amygdala, suggesting that structural deficits might underlie alterations in function. In addition, some regions exhibited only structural abnormalities in PTSD, including the ACC/mPFC, striatum, insula, primary visual, auditory and sensorimotor cortices. Moreover, consistent alterations in PTSD patients across languages may draw attention to the disparity in multi-cultural considerations in psychiatric research and further understanding the neurophysiopathology of PTSD.

Shape analysis of the subcortical structures in North Korean refugees with post-traumatic stress disorder and major depressive disorder

BACKGROUND

Despite the growing number of refugees and their mental health issues, neurobiological mechanisms to explain clinical symptoms resulting from traumatic events, such as post-traumatic stress disorder (PTSD) or major depressive disorder (MDD), have not been extensively investigated. Research on the mental health of North Korean refugees (NKRs) who defected to South Korea for resettlement is still at an early stage but commonly reports structural and functional abnormalities in brain regions related to reward and motivational processing. The nucleus accumbens (NAc) and ventral pallidum (VP) are the major sites in subcortical structures that play key roles in reward and motivation.

METHODS

The present study examined subcortical structural abnormalities of 28 NKRs and age-, sex- matched South Korean Controls (SKCs) using shape analysis at the vertex level.

RESULTS

Among the 28 NKRs, 18 had psychiatric disorders, including PTSD and MDD. The NKRs showed significantly reduced volumes in the right NAc and bilateral VP compared to the SKRs. The volume of the right VP showed a significant negative correlation with current PTSD severity in the NKR group.

CONCLUSIONS

Our findings demonstrated that structural alterations of the NAc and VP may explain PTSD and MDD observed in the refugees and further suggest that the aftereffect of trauma, manifested as anhedonia and anxiety, may show chronically.

Trauma and alcohol characteristics related to high intensity binge drinking during college

High intensity (HI) binge drinking has emerged as a high-risk drinking phenotype in young adult drinkers, yet few studies have evaluated clinically meaningful correlates of HI binge drinking among young adults at risk for co-occurring psychopathologies, such as interpersonal trauma-exposed drinkers. The present study compared three groups (i.e., HI binge, standard binge, non-binge drinkers) of interpersonal trauma-exposed college student drinkers (N = 221) on alcohol and interpersonal trauma characteristics. Results of one-way ANOVAs indicated that the HI binge group endorsed significantly greater negative alcohol-related consequences relative to the other two groups. The HI binge group endorsed significantly greater enhancement motives compared to the non-binge group, and no group differences were detected for PTSD and interpersonal trauma characteristics. Individuals who engage in HI binge drinking may experience greater alcohol problems due to their use of alcohol to enhance positive mood. HI binge drinking does not differentiate individuals on the basis of interpersonal trauma experiences or related psychopathology.

The associations between posttraumatic stress disorder and delay discounting, future orientation, and reward availability: A behavioral economic model

The theoretical framework of behavioral economics, a metatheory that integrates operant learning and economic theory, has only recently been applied to posttraumatic stress disorder (PTSD). A behavioral economic theory of PTSD reflects an expansion of prior behavioral conceptualization of PTSD, which described PTSD in terms of respondent and operant conditioning. In the behavioral economic framework of PTSD, negatively reinforced avoidance behavior is overvalued, in part due to deficits in environmental reward, and may be conceptualized as a form of reinforcer pathology (i.e., excessive preference for and valuation of an immediate reinforcer). We investigated cross-sectional relationships between PTSD severity and several constructs rooted in this behavioral economic framework, including future orientation, reward availability, and delay discounting in a sample of 110 military personnel/veterans (87.2% male) who had served combat deployments following September 11, 2001. Total PTSD severity was inversely related to environmental reward availability, β = -.49, ΔR² = 0.24, p < .001; hedonic reward availability, β = -.32, ΔR² = 0.10, p = .001; and future orientation, β = -.20, ΔR² = 0.04, p = .032, but not delay discounting, r = -.05, p = .633. An examination of individual symptom clusters did not suggest that avoidance symptoms were uniquely associated with these behavioral economic constructs. The findings offer support for a behavioral economic model of PTSD in which there is a lack of positive reinforcement as well as a myopic focus on the present.

"Staying alive" in the context of intimate partner abuse

Females are disproportionately affected by intimate partner abuse that can result in severe physical and mental harm. Benenson et al. provide little exploration of how female-evolved traits enhance females' survival in abusive relationships. Discussion centres on "why" females do not "just leave" an abusive relationship and the effectiveness of female-evolved traits in navigating intimate partner abuse over time.

Wanting, Liking, and Missing Out: Exploring the Role of Reward Functioning in the Overlap Between PTSD and Depression

ABSTRACT

Diminished reward functioning (anhedonia) is an aspect of multiple psychiatric diagnoses and is a critical component of depression, yet it has rarely been examined in the context of posttraumatic stress disorder (PTSD). Deficits in reward function may be a transdiagnostic factor contributing to the high rate of comorbidity between PTSD and depression. The present study examined the commonality and distinction between PTSD and depression and their relationship to reward functioning using a bifactor model in a sample of 106 trauma-exposed undergraduates. Results indicated a strong commonality factor between PTSD and depression. Of three indices of reward functioning (i.e., hedonic pleasure, reward motivation, and environmental reward availability), environmental reward availability alone was related to unique latent factors for PTSD and depression, and their commonality. Findings suggest that environmental context may be the key to understanding the role of reward in PTSD, depression, and psychopathology broadly.

Childhood Maltreatment and Anhedonic Symptoms: Test of a Dual-risk Model in Emerging Adults

Anhedonia, defined as deficits in positive affect and approach related behaviors, remains an understudied trauma response. As anhedonic responses to interpersonal violence are associated with a more severe course of psychopathology that is more difficult to treat, an increased focus on risk factors for anhedonia is necessary. The present study sought to address this gap in the literature by testing a theoretical model that highlights two transdiagnostic pathways leading to anhedonic responses in emerging adults attending college. Specifically, our study examined how childhood maltreatment subtypes (a) uniquely associate with depressive and post-traumatic stress (PTS) manifestations of anhedonia and (b) how temperament (i.e., anticipatory positive affect) and distress (i.e., negative mood) explain these relations. At baseline, a racially diverse sample of 462 emerging adults (Age_Mean = 19.45; 75.5% female; 45.5% White) completed self-report forms on childhood abuse and neglect, anticipatory positive affect, negative mood, and anhedonia. Individuals completed measures of temperament and psychological distress again 6-weeks, and 12-weeks later. Latent growth curve models were utilized to test our model. Consistent with hypotheses, deficits in anticipatory positive affect uniquely explained the relation between neglect and depressive/PTS anhedonic symptoms. Meanwhile, negative mood mediated the relation between abuse and both forms of anhedonia. These findings support the theory that two separate risk pathways lead to anhedonia. Support for our model suggests that distinguishing between pathways for anhedonic responses may be the key to a more targeted, transdiagnostic, trauma-informed approach for treating and preventing these deleterious, treatment-resistant, internalizing symptoms.

Emotional processing prospectively modulates the impact of anxiety on COVID-19 pandemic-related post-traumatic stress symptoms: an ERP study

BACKGROUND

Considering that the elevated distress caused by the COVID-19 pandemic, in some cases, led to post-traumatic stress symptoms (PTSS), it has been proposed as a specific traumatic event. The present longitudinal study investigated pre-pandemic motivated attention to emotional stimuli, as indexed by Late Positive Potential (LPP) amplitude, in relation with the potential differential role of anxiety and depressive symptoms in predicting PTSS severity related to the COVID-19 pandemic.

METHODS

A total of 79 university students initially completed self-report measures of depression and anxiety along with a passive viewing task of emotional (pleasant, unpleasant) and neutral pictures while electroencephaloghic activity was recorded. In December 2020, 57 participants completed a questionnaire assessing PTSS.

RESULTS

Significant interactions between anxiety and LPP emerged in predicting pandemic-related PTSS, where greater anxiety symptoms predicted PTSS only in individuals with greater LPP to unpleasant or with reduced LPP to pleasant stimuli.

LIMITATIONS

The prevalence of the female sex, the relatively young age of the participants, as well as the fact that they were all enrolled in a University course might not allow the generalization of the findings.

CONCLUSIONS

Taken together, the present longitudinal study provided novel evidence on EEG predictors of pandemic-related PTSS that might be useful for the prevention and treatment of PTSS. Indeed, assessing anxiety symptoms and pre-trauma LPP to emotional stimuli might be a useful target for identifying individuals that are more vulnerable to the development of PTSS during times of crisis.

[Comorbidity of posttraumatic stress disorder and addiction from a biopsychosocial perspective]

Posttraumatic stress disorder and substance use disorder often co-occur within the health care system. Their comorbidity is associated with more serious acute clinical symptomatology, more frequent hospital admissions in state of emergency and significantly lower chances of improvement by psychological and pharmacological treatment. Their comorbidity contributes to dramatically unfavourable courses of illness as regards all biopsychosocial levels. The survey presented will discuss empirical findings from various perspectives: general epidemiology, substance use disorder as risk factor of trauma and PTSD, trauma and PTSD as risk factor of SUD, neurobiological effects of SUD converging towards neurobiology of PTSD, shared common factors of genetics/epigenetics, personality traits, and early developmental stress and trauma. The main focus of analysis will be put on processes that are intrinsically linked to the development and course of both disorders.

The Transdiagnostic Nature of Social Anhedonia: Historical and Current Perspectives

In this chapter, we trace the historical roots of the social anhedonia (SoA) construct to current conceptualizations. We first describe the aspects of SoA that distinguish it from anhedonia in general. We summarize evidence that SoA is a transdiagnostic symptom and risk factor. Although several forms of psychopathology are associated with elevated rates of self-reported SoA, one unresolved issue is whether the processes and mechanisms underlying SoA in one disorder are the same as the processes and mechanisms underlying SoA seen in another disorder. We assert that there may be different causal factors underlying SoA across disorders. Considering both the principles of equifinality and multifinality, we offer an integrative model for social reward processing. This conceptualization considers roles for the following: attention; social cognition, including, but not limited to, social skills; reward learning and valuation; working memory; anticipation, prediction, and remembering; and motivation and effort. We conclude that SoA may be caused by multiple underlying impairments, all of which may serve as targets for intervention. This conceptualization is provided as an impetus for further research in the area.

Validity and utility of Hierarchical Taxonomy of Psychopathology (HiTOP): III. Emotional dysfunction superspectrum

The Hierarchical Taxonomy of Psychopathology (HiTOP) is a quantitative nosological system that addresses shortcomings of traditional mental disorder diagnoses, including arbitrary boundaries between psychopathology and normality, frequent disorder co-occurrence, substantial heterogeneity within disorders, and diagnostic unreliability over time and across clinicians. This paper reviews evidence on the validity and utility of the internalizing and somatoform spectra of HiTOP, which together provide support for an emotional dysfunction superspectrum. These spectra are composed of homogeneous symptom and maladaptive trait dimensions currently subsumed within multiple diagnostic classes, including depressive, anxiety, trauma-related, eating, bipolar, and somatic symptom disorders, as well as sexual dysfunction and aspects of personality disorders. Dimensions falling within the emotional dysfunction superspectrum are broadly linked to individual differences in negative affect/neuroticism. Extensive evidence establishes that dimensions falling within the superspectrum share genetic diatheses, environmental risk factors, cognitive and affective difficulties, neural substrates and biomarkers, childhood temperamental antecedents, and treatment response. The structure of these validators mirrors the quantitative structure of the superspectrum, with some correlates more specific to internalizing or somatoform conditions, and others common to both, thereby underlining the hierarchical structure of the domain. Compared to traditional diagnoses, the internalizing and somatoform spectra demonstrated substantially improved utility: greater reliability, larger explanatory and predictive power, and greater clinical applicability. Validated measures are currently available to implement the HiTOP system in practice, which can make diagnostic classification more useful, both in research and in the clinic.

The Neural Circuitry of Reward During Sustained Threat

Reward processing is important for understanding behavior in psychopathology. Opportunities to earn money activate the ventral striatum, as shown by the monetary incentive delay (MID) task. Anxiety conditions have been modeled by presenting shocks and startling sounds. To further investigate the co-occurrence of an anxiety condition and a rewarding stimulus, we modified the MID to include a sustained threat of scream. This study investigated neural patterns of the MID task with an uncertain threat of a startling scream. Forty-three young adults completed a functional MRI scan. The task included two conditions (scream and safe) and three cues (gain $5, gain $0, lose $5). Analyses included a whole brain, group analysis using a linear mixed-effects model and a paired t-test. The whole brain analysis revealed a main effect of cue, with increased ventral striatal activation (F₂,₂₁₀ = 58.8, p < 0.001) during cues to gain or lose $5. We observed a main effect of condition during cue presentation, such that bilateral insula and putamen activation was diminished (p < 0.001) in the scream versus the safe condition. A t-test of condition showed increased activation during threat blocks in the insula and putamen. A time course graph revealed that activation in the insula and putamen responded similarly to incentive but had an overall elevation during the scream condition. These results replicated expected activation in reward and in the setting of uncertain threat. Our results show that uncertain threat increases the magnitude of activation in the dorsal striatum.

A cross-species assay demonstrates that reward responsiveness is enduringly impacted by adverse, unpredictable early-life experiences

Exposure to early-life adversity (ELA) is associated with several neuropsychiatric conditions, including major depressive disorder, yet causality is difficult to establish in humans. Recent work in rodents has implicated impaired reward circuit signaling in anhedonic-like behavior after ELA exposure. Anhedonia, the lack of reactivity to previously rewarding stimuli, is a transdiagnostic construct common to mental illnesses associated with ELA. Here, we employed an assay of reward responsiveness validated across species, the Probabilistic Reward Task (PRT). In the PRT, healthy participants reliably develop a response bias toward the more richly rewarded stimulus, whereas participants with anhedonia exhibit a blunted response bias that correlates with current and future anhedonia. In a well-established model of ELA that generates a stressful, chaotic, and unpredictable early-life environment, ELA led to blunted response biases in the PRT in two separate cohorts, recapitulating findings in humans with anhedonia. The same ELA rats had blunted sucrose preference, further supporting their anhedonic-like phenotypes. Probing the aspects of ELA that might provoke these deficits, we quantified the unpredictability of dam/pup interactions using entropy measures and found that the unpredictability of maternal care was significantly higher in the ELA groups in which PRT and sucrose preference reward deficits were present later in life. Taken together, these data position the PRT, established in clinical patient populations, as a potent instrument to assess the impact of ELA on the reward circuit across species. These findings also implicate the unpredictability of maternal signals during early life as an important driver of reward sensitivity deficits.

Psychophysiological predictors of change in emotion dysregulation 6 months after traumatic injury

Emotion dysregulation that occurs after trauma conveys risk for multiple disorders, including posttraumatic stress disorder, depression, and anxiety. Psychophysiological data (e.g., skin conductance level [SCL]) may be a useful biomarker for quantifying emotion dysregulation given that autonomic nervous system (ANS)-mediated arousal may underlie this feature. In this longitudinal study, we tested whether SCL collected following a single-incident traumatic injury could predict changes in emotion dysregulation over 6 months. Sixty-six adults were recruited from the emergency department; SCL was quantified during an active trauma narrative, in which participants re-told their traumatic event to a research staff member, as well as a neutral narrative for a control condition. Change in SCL (ΔSCL) was calculated using a maximum activation - minimum activation difference score. Multilevel linear modeling was used to test ΔSCL as a predictor of emotion dysregulation using the Emotion Dysregulation Scale (EDS) over time (3 timepoints over 6 months). Results showed that greater ΔSCL - indicative of increasing arousal- during both the trauma (p = 0.037) and neutral (p = 0.013) narratives was a significant predictor of greater emotion dysregulation at each subsequent timepoint. Further, we found a ΔSCL by time interaction, such that less ΔSCL during the neutral narrative predicted decreased emotion dysregulation over time (b = -1.26, SE = 0.43, t = -2.91, p = 0.004). Results validate the use of lab-based assessments of arousal to study emotion dysregulation in trauma survivors. That recovery from emotion dysregulation was predicted by less arousal during a neutral event underscores the importance of clinically targeting response to safety in trauma survivors.