Social anhedonia and clinical outcomes in early adulthood: A three-year follow-up study within a community sample

Psychosis superspectrum I: Nosology, etiology, and lifespan development

This review describes the Hierarchical Taxonomy of Psychopathology (HiTOP) model of psychosis-related psychopathology, the psychosis superspectrum. The HiTOP psychosis superspectrum was developed to address shortcomings of traditional diagnoses for psychotic disorders and related conditions including low reliability, arbitrary boundaries between psychopathology and normality, high symptom co-occurrence, and heterogeneity within diagnostic categories. The psychosis superspectrum is a transdiagnostic dimensional model comprising two spectra-psychoticism and detachment-which are in turn broken down into fourteen narrow components, and two auxiliary domains-cognition and functional impairment. The structure of the spectra and their components are shown to parallel the genetic structure of psychosis and related traits. Psychoticism and detachment have distinct patterns of association with urbanicity, migrant and ethnic minority status, childhood adversity, and cannabis use. The superspectrum also provides a useful model for describing the emergence and course of psychosis, as components of the superspectrum are relatively stable over time. Changes in psychoticism predict the onset of psychosis-related psychopathology, whereas changes in detachment and cognition define later course. Implications of the superspectrum for genetic, socio-environmental, and longitudinal research are discussed. A companion review focuses on neurobiology, treatment response, and clinical utility of the superspectrum, and future research directions.

Teleosts as behaviour test models for social stress

Stress is an important aspect of our everyday life and exposure to it is an unavoidable occurrence. In humans, this can come in the form of social stress or physical stress from an injury. Studies in animal models have helped researchers to understand the body's adaptive response to stress in human. Notably, the use of behavioural tests in animal models plays a pivotal role in understanding the neural, endocrine and behavioural changes induced by social stress. Under socially stressed conditions, behavioural parameters are often measured physiological and molecular parameters as changes in behaviour are direct responses to stress and are easily assessed by behavioural tests. Throughout the past few decades, the rodent model has been used as a well-established animal model for stress and behavioural changes. Recently, more attention has been drawn towards using fish as an animal model. Common fish models such as zebrafish, medaka, and African cichlids have the advantage of a higher rate of reproduction, easier handling techniques, sociability and most importantly, share evolutionary conserved genetic make-up, neural circuitry, neuropeptide molecular structure and function with mammalian species. In fact, some fish species exhibit a clear diurnal or seasonal rhythmicity in their stress response, similar to humans, as opposed to rodents. Various social stress models have been established in fish including but not limited to chronic social defeat stress, social stress avoidance, and social stress-related decision-making. The huge variety of behavioural patterns in teleost also aids in the study of more behavioural phenotypes than the mammalian species. In this review, we focus on the use of fish models as alternative models to study the effects of stress on different types of behaviours. Finally, fish behavioural tests against the typical mammalian model-based behavioural test are compared and discussed for their viability.

Anhedonia and suicidal ideation in young people with early psychosis: Further findings from the 2-year follow-up of the ReARMS program

Hedonic deficits have been extensively studied in schizophrenia, but little is known about their association with suicidal ideation in early psychosis. The aim of this research was to examine the relationship between anhedonia and suicidal thoughts across a 2-year follow-up period in people with First Episode Psychosis (FEP) and at Ultra High Risk (UHR) of psychosis. Ninty-six UHR and 146 FEP, aged 13-35 years, completed the Comprehensive Assessment of At-Risk Mental States (CAARMS) and the Beck Depression Inventory-II (BDI-II). The BDI-II "Anhedonia" subscale score to assess anhedonia and the CAARMS "Depression" item 7.2 subscore to measure depression were used across the 2 years of follow-up. Hierarchical regression analyses were performed. No difference in anhedonia scores between FEP and UHR individuals was found. In the FEP group, a significant enduring association between anhedonia and suicidal ideation was found at baseline and across the follow-up, independent of clinical depression. In the UHR subgroup, the enduring relationship between anhedonia and suicidal thoughts were not completely independent from depression severity. Anhedonia is relevant in predicting suicidal ideation in early psychosis. Specific pharmacological and/or psychosocial interventions on anhedonia within specialized EIP program could reduce suicide risk overtime.

Anhedonia and sensitivity to punishment in schizophrenia, depression and opiate use disorder

BACKGROUND

From a behavioural perspective anhedonia is defined as diminished interest in the engagement of pleasurable activities. Despite its presence across a range of psychiatric disorders, the cognitive processes that give rise to anhedonia remain unclear.

METHODS

Here we examine whether anhedonia is associated with learning from positive and negative outcomes in patients diagnosed with major depression, schizophrenia and opiate use disorder alongside a healthy control group. Responses in the Wisconsin Card Sorting Test - a task associated with healthy prefrontal cortex function - were fitted to the Attentional Learning Model (ALM) which separates learning from positive and negative feedback.

RESULTS

Learning from punishment, but not from reward, was negatively associated with anhedonia beyond other socio-demographic, cognitive and clinical variables. This impairment in punishment sensitivity was also associated with faster responses following negative feedback, independently of the degree of surprise.

LIMITATIONS

Future studies should test the longitudinal association between punishment sensitivity and anhedonia also in other clinical populations controlling for the effect of specific medications.

CONCLUSIONS

Together the results reveal that anhedonic subjects, because of their negative expectations, are less sensitive to negative feedbacks; this might lead them to persist in actions leading to negative outcomes.

The role of anhedonia in predicting risk-taking behavior in university students

There is a growing interest in understanding symptoms of psychological distress, such as anhedonia, not just as related to individual psychological disorders, but transdiagnostically. This broader focus allows for the investigation of the effects of symptoms across disorders, or in non-clinical samples. Previous work has linked anhedonia and risk-taking behavior in clinical samples, though the exploration of this relationship in healthy adolescents and early adults is still a relatively new area of research. The current study explored the relationship between variability in anhedonia and risk-taking behavior by breaking each into separable parts (i.e. anhedonia into deficits in anticipatory and consummatory pleasure; risk-taking into risk propensity, sub-optimal risky behavior, and response to punishment). A sample of 81 university students completed two Chapman scales of anhedonia, the Temporal Experience of Pleasure Scale (TEPS), and the Balloon Analogue Risk Task (BART). Hierarchical linear regression analyses were completed to assess the predictive power of each anhedonia measure on each outcome measure on the BART. TEPS score significantly negatively predicted all three outcome measures, with anticipatory pleasure having more predictive power than consummatory pleasure. Physical anhedonia was also a significant predictor of sub-optimal risky behavior and response to punishment. These findings present a broader and more complex view of the associations between anhedonia and risk than have previously been reported, and merit further study to continue to elucidate how they are related to one another.

Examining associations between social anhedonia and convergent thinking using the Remote Associates Test

Introduction: Social anhedonia (SocAnh) predicts increased risk of schizophrenia-spectrum disorders, with evidence that these disorders are associated with increased creativity. However, it is still largely unknown whether SocAnh is associated with one central aspect of creative thinking, convergent thinking.Methods: In two studies, college students with either extreme levels of SocAnh (n = 44 and n = 70) or controls with an average level of SocAnh (n = 111 and n = 100) completed a convergent thinking task, the Remote Associates Test, and also completed measures of current affect. In the second study, participants also completed a divergent thinking task.Results: In both studies, the SocAnh group had better performance than controls on the convergent thinking task. Further, this group difference remained after removing shared variance with current affect. In Study 2, groups did not differ on divergent thinking.Conclusions: Overall, consistent with research linking schizophrenia-spectrum disorders and creativity, the current research suggests that SocAnh is associated with increases in some aspects of creativity.

Rodent models of early adversity: Impacts on developing social behavior circuitry and clinical implications

Flexible and context-appropriate social functioning is key for survival across species. This flexibility also renders social behavior highly plastic, particularly during early development when attachment to caregiver can provide a template for future social processing. As a result, early caregiving adversity can have unique and lasting impacts on social behavior and even confer vulnerability to psychiatric disorders. However, the neural circuit mechanisms translating experience to outcome remain poorly understood. Here, we consider social behavior scaffolding through the lens of reward and threat processing. We begin by surveying several complementary rodent models of early adversity, which together have highlighted impacts on neural circuits processing social cues. We next explore these circuits underlying perturbed social functioning with focus on dopamine (DA) and its role in regions implicated in social and threat processing such as the prefrontal cortex (PFC), basolateral amygdala (BLA) and the lateral habenula (LHb). Finally, we turn to human populations once more to examine how altered DA signaling and LHb dysfunction may play a role in social anhedonia, a common feature in diagnoses such as schizophrenia and major depressive disorder (MDD). We argue that this translational focus is critical for identifying specific features of adversity that confer heightened vulnerability for clinical outcomes involving social cue processing.

Social brain network predicts real-world social network in individuals with social anhedonia

Social anhedonia (SA) impairs social functioning in schizophrenia. Previous evidence suggested that certain brain regions predict longitudinal change of real-world social outcomes, yet previous study designs have failed to capture the corresponding functional connectivity among the brain regions involved. This study measured the real-world social network in 22 pairs of individuals with high and low levels of SA, and followed up them for 21 months. We further explored whether resting-state social brain network characteristics could predict the longitudinal variations of real-world social network. Our results showed that social brain network characteristics could predict the change of real-world social networks in both the high SA and low SA groups. However, the results differed between the two groups, i.e., the topological characteristics of the social brain network predicted real-world social network change in the high SA group; whereas the functional connectivity within the social brain network predicted real-world social network change in the low SA group. Principal component analysis and linear regression analysis on the entire sample showed that the functional connectivity component centered at the right orbital inferior frontal gyrus could best predict social network change. Our findings support the notion that social brain network characteristics could predict social network development.

Cognitive Functioning and Schizotypy: A Four-Years Study

Although there is ample evidence from cross-sectional studies indicating cognitive deficits in high schizotypal individuals that resemble the cognitive profile of schizophrenia-spectrum patients, there is still lack of evidence by longitudinal/follow-up studies. The present study included assessments of schizotypal traits and a wide range of cognitive functions at two time points (baseline and 4-years assessments) in order to examine (a) their stability over time, (b) the predictive value of baseline schizotypy on cognition at follow-up and (c) differences in cognition between the two time points in high negative schizotypal and control individuals. Only high negative schizotypal individuals were compared with controls due to the limited number of participants falling in the other schizotypal groups at follow-up. Seventy participants (mean age: 36.17; 70% females) were assessed at baseline and follow-up. Schizotypal traits were evaluated with the Schizotypal Personality Questionnaire. We found that schizotypal traits decreased over time, except in a sub-group of participants ("schizotypy congruent") that includes individuals who consistently meet normative criteria of inclusion in either a schizotypal or control group. In these individuals, negative schizotypy and aspects of cognitive-perceptual and disorganized schizotypy remained stable. The stability of cognitive functioning also varied over time: response inhibition, aspects of cued attention switching, set-shifting and phonemic/semantic verbal fluency improved at follow-up. High negative schizotypy at baseline predicted poorer response inhibition and semantic switching at follow-up while high disorganized schizotypy predicted poorer semantic processing and complex processing speed/set-shifting. The between-group analyses revealed that response inhibition, set-shifting and complex processing speed/set-shifting were poorer in negative schizotypals compared with controls at both time points, while maintaining set and semantic switching were poorer only at follow-up. Taken together, the findings show differential stability of the schizotypal traits over time and indicate that different aspects of schizotypy predict a different pattern of neuropsychological task performance during a 4-years time window. These results are of significant use in the formulation of targeted early-intervention strategies for high-risk populations.