Reward processing in schizophrenia: a deficit in the representation of value

Digital phenotyping evidence for the reduced positivity offset as a mechanism underlying anhedonia among individuals at clinical high-risk for psychosis

Prior studies suggest that the "anhedonia paradox" in schizophrenia (i.e., discrepant results indicating intact hedonic reactivity despite reduced frequency of pleasure-seeking activity) can be explained by a reduction in the "positivity offset" (i.e., a reduction in the normative tendency to experience greater positive than negative affect during low arousal neutral contexts that promote reward-seeking behavior). In the current study, we examined whether the positivity offset is relevant to explaining anhedonia and liability for psychosis among individuals at clinical high-risk for psychosis (CHR) (i.e., individuals exhibiting attenuated hallucinations or delusions that cause distress and functional decline). Mathematical modeling approaches from Cacioppo's Evaluative Space Model were applied to six days of digital phenotyping data collected in daily life among 100 individuals at CHR and 57 healthy controls (CN). Participants reported levels of positive emotion, negative emotion, and arousal throughout the day via ecological momentary assessment (EMA) surveys while accelerometry was passively recorded. EMA surveys were used to calculate the positivity offset and examine associations with real-world motivated behavior. Results indicated that the positivity offset was present among individuals at CHR, but diminished compared to CN. Importantly, smaller positivity offset scores were associated with greater clinically rated anhedonia, particularly among CHR cases with comorbid mood disorder diagnoses. Findings suggest that reductions in the positivity offset are a mechanism underlying anhedonia across phases of psychotic illness and represent a novel treatment target that is relevant for the treatment of negative symptoms and prevention of psychotic disorders.

Avolition predicts variability in optimal risk-taking in early psychosis

BACKGROUND

Adolescence and early adulthood are associated with increased risk-taking, with a growing understanding that risk-taking may be adaptive during this developmental period. In psychosis, failure to appropriately engage in optimal risk-taking due to altered reward processing may contribute to poor social and role functioning. We investigated differences in optimal risk-taking in early psychosis (EP), as well as the relationship between optimal risk-taking and the negative symptom of avolition.

METHODS

Fifty-six EP participants and 52 healthy controls (HC) completed a modified version of the Balloon Analog Risk Task (BART). In the BART, individuals inflated a virtual balloon to gain points; if the balloon exploded, no points were gained. We manipulated degree of risk, such that trials were low-risk (high probability of reward, low probability of punishment) or high-risk (low probability of reward, high probability of punishment). We investigated differences between EP and HC in (1) risk-propensity on low- and high-risk trials, (2) total adverse outcomes, and (3) behavior changes following punishment.

RESULTS

There were no significant differences between EP and HC on any BART metrics; however, in EP, the negative symptom of avolition was associated with reduced risk-propensity on low-risk trials and reduced risk-taking immediately following punishment on low-risk trials. In the high-risk condition, avolition was not associated with risk-propensity, number of adverse outcomes, or behavior following punishment.

CONCLUSIONS

These results suggest that risk-taking and response to punishment in high-risk situations may be preserved in psychosis, and that in lower-risk situations that allow for greater variability, behavior may be moderated by negative symptom severity.

Higher motivation and pleasure scores predict more reliance on model-free decision making

Decision making is driven by factors such as motivation, pleasure, and cognitive skill. The current study evaluates how these factors are related to decision making in a community population. In recent years, work in the field of reinforcement learning has identified two main pathways that drive decision making: model-based and model-free learning. Model-free learning updates action values retrospectively, after a reward is received. In contrast, model-based learning updates action values prospectively, by weighing contextual factors, the overall structure of the situation, and reward received. The current study utilizes a two-stage decision-making task to assess the relative contribution of model-free versus model-based learning in relation to measures that assess motivation, pleasure, and cognition in a community sample (n = 127). Generalized linear mixed-effect models showed that individuals high in motivation and pleasure had significantly greater reliance on model-free decision making (p = 0.0267). In contrast, individuals with better working memory, as measured by a running span task, had significantly greater reliance on model-based learning (p = 0.0003). These findings provide evidence that individual differences in motivation and cognition are associated with reliance on particular learning pathways. It has been suggested that lower levels of motivation, pleasure, and cognition in various forms of psychopathology (e.g., depression) can impair decision making. Our results show these relationships transcend clinical contexts. Specifically, these findings suggest that individuals who experience low motivation and pleasure may be less sensitive to immediate rewards, and that working memory capacity is highly relevant to model-based learning.

Childhood anhedonia symptoms and stressful life events predict the development of reward-related brain activity across adolescence

The reward positivity (RewP) is an event-related potential that indexes reinforcement learning and reward system activation. The RewP has been shown to increase across adolescence; however, most studies have examined the RewP across two assessments, and no studies have examined within-person changes across adolescence into young adulthood. Moreover, the RewP has been identified as a neurobiological risk factor for adolescent-onset depression, but it is unclear whether childhood psychosocial risk factors might predict RewP development across adolescence. In a sample of 317 8- to 14-year-old girls (Mage = 12.4, SD = 1.8), the present study examined self-report measures of depression symptoms and stressful life events at baseline and the ΔRewP during the doors guessing task across three timepoints. Growth modeling indicated that, across all participants, the ΔRewP did not demonstrate linear change across adolescence. However, baseline anhedonia symptoms predicted within-person changes in the ΔRewP, such that individuals with low anhedonia symptoms demonstrated a linear increase in the ΔRewP, but individuals with high anhedonia symptoms had no change in the ΔRewP across adolescence. Similar patterns were observed for stressful life events. The present study suggests that childhood risk factors impact the development of reward-related brain activity, which might subsequently increase risk for psychopathology.

Reward Processing in Mood Disorders and Schizophrenia: A Neurodevelopmental Framework

Major depressive disorder (MDD), bipolar disorder, and schizophrenia involve disruptions in processing rewarding stimuli. In this review, we propose that distinct mechanistic pathways underlie these disruptions in mood disorders versus schizophrenia, and we highlight the importance of understanding these differences for developing personalized treatments. We summarize evidence suggesting that reward processing abnormalities in mood disorders are driven by dysregulated motivational systems; MDD is characterized by blunted responses to reward cues, and bipolar disorder is characterized by heightened responses. In contrast, we argue that reward processing disruptions in schizophrenia do not reflect abnormalities in motivation or hedonic experience; rather, they reflect impairments in the cognitive representation of past and future rewards as well as misdirected attention to irrelevant stimuli. To integrate these findings, we present a neurodevelopmental framework for the onset of mood and psychotic disorders and explore how disruptions in normative brain development contribute to their pathophysiology, timing, and onset. Additionally, we move beyond viewing these conditions as homogeneous disorders and discuss how reward processing profiles may align with specific symptom dimensions.

Inflammation is associated with avolition and reduced resting state functional connectivity in corticostriatal reward circuitry in patients with schizophrenia

Low-grade inflammation has been associated with negative symptoms in patients with schizophrenia. Of these symptoms, deficits in motivation and pleasure, especially in the domain of avolition, are particularly disabling. Effects of inflammation on motivational deficits in patients with depression are associated with disruptions in corticostriatal reward circuitry involving the inferior ventral striatum (iVS) and ventromedial prefrontal cortex (vmPFC). Accordingly, we examined the relationships among inflammation, negative symptoms, and corticostriatal reward circuitry in patients with schizophrenia. Negative symptoms and high sensitivity C-reactive protein (hsCRP) were obtained in 57 individuals with schizophrenia. Resting state functional connectivity (rsFC) was obtained from a subset of 43 of these individuals. Associations were tested between hsCRP and the motivation and pleasure (MAP) and expressivity (EXP) dimensions of the Brief Negative Symptom Scale (BNSS) as well as targeted rsFC between iVS and vmPFC. Covariates in all statistical models included age, sex, race, smoking, body mass index, depression, and chlorpromazine equivalents. hsCRP was significantly associated with BNSS MAP (β = 0.34, pcorr = 0.022, specifically the domains of avolition and asociality (p < 0.05), but not BNSS EXP (β = -0.17, pcorr = 0.57) or the domains of blunted affect or alogia (both p > 0.05). hsCRP was also significantly associated with decreased rsFC from right iVS to vmPFC (β=-0.37, pcorr = 0.029), which in turn, was associated with increased avolition in individuals with higher (hsCRP >2 mg/L) but not lower inflammation (β=-14.01, p = 0.007 vs. β = 0.07, p = 0.77, respectively). hsCRP was associated with reduced avolition and corticostriatal rsFC in patients with schizophrenia and increased inflammation, underscoring the need for further research to replicate these associations with brain connectivity changes in this subgroup of individuals with schizophrenia.

Computational modeling of reversal learning impairments in schizophrenia and bipolar disorder reveals shared failure to exploit rewards

The distinction between the concepts of schizophrenia and bipolar disorder is fundamental to the Kraepelinian tradition in psychiatry. One mechanism undergirding this distinction, a difference in reward sensitivity, has been championed by a number of scholars. As part of the Cognitive Neuroscience Test Reliability and Clinical applications for Serious mental illnesses consortium, 225 participants including people with schizophrenia (n = 69), schizoaffective disorder (n = 55), and bipolar affective disorder (n = 53) performed a probabilistic reversal learning task. This task switches the rewarded stimulus at various times throughout the task. Our analyses leveraged a Hidden Markov Model to examine trial-by-trial decisions of participants to reveal the differences between patient groups in their response to reward feedback. Whereas no patient group showed difficulty reversing their preferred categories after a switch in the task's contingencies and bipolar patient performance was spared in some other ways, all patient groups made more errors throughout the task because of a greater tendency to shift away from rewarded categories (i.e., win-switching). Furthermore, patients' cognitive ability is specifically related to this aspect of the task. Rather than validating a Kraepelinian dichotomy, these findings suggest that a failure to exploit rewards may reflect a mechanistic deficit common across both affective and nonaffective psychoses related to cognitive impairments in patients. (PsycInfo Database Record (c) 2025 APA, all rights reserved).

Anhedonia Across and Beyond the Schizophrenia Spectrum

Anhedonia refers to the diminished ability to experience pleasure, and is a core feature of schizophrenia (SCZ). The neurocognitive and neural correlates of anhedonia remain elusive. Based on several influential theoretical models for negative symptoms, this selective review proposed four important neurocognitive domains, which may unveil the neurobiological mechanisms of anhedonia. The authors critically reviewed the current evidence regarding value representation of reward, prospection, emotion-behavior decoupling, and belief updating in the Chinese setting, covering both behavioral and neuroimaging research. We observed a limited application of the transdiagnostic approach in previous studies on the four domains, and the lack of adequate measures to tap into the expressivity deficit in SCZ. Despite many behavioral paradigms for these four domains utilized both social and non-social stimuli, previous studies seldom focused on the social-versus-non-social differentiation. We further advocated several important directions for future research.

Randomized Laboratory Study of Single-Dose Cannabis, Dronabinol, and Placebo in Patients With Schizophrenia and Cannabis Use Disorder

BACKGROUND AND HYPOTHESIS

Up to 43% of people with schizophrenia have a lifetime cannabis use disorder (CUD). Tetrahydrocannabinol (THC) has been shown to exacerbate psychosis in a dose-dependent manner, but little research has assessed its effects on schizophrenia and co-occurring CUD (SCZ-CUD). In this double-dummy, placebo-controlled trial (total n = 130), we hypothesized that a modest dose of THC would worsen cognitive function but not psychosis.

STUDY DESIGN

Effects of single-dose oral THC (15 mg dronabinol) or smoked 3.5% THC cigarettes vs placebo in SCZ-CUD or CUD-only on positive and negative symptoms of schizophrenia (only for SCZ-CUD), cognition, and drug experiences assessed several hours after drug administration. SCZ-only and healthy control participants were also assessed.

STUDY RESULTS

Drug liking was higher in THC groups vs placebo. Neither smoked THC nor oral dronabinol predicted positive or negative symptom subscale scores 2 and 5 h, respectively, after drug exposure in SCZ-CUD participants. The oral dronabinol SCZ-CUD group, but not smoked THC SCZ-CUD group, performed worse than placebo on verbal learning (B = -9.89; 95% CI: -16.06, -3.18; P = .004) and attention (B = -0.61; 95% CI: -1.00, -0.23; P = .002). Every 10-point increment in serum THC + THCC ng/ml was associated with increased negative symptoms (0.40 points; 95% CI: 0.15, 0.65; P = .001; subscale ranges 7-49) and trends were observed for worse positive symptoms and performance in verbal learning, delayed recall, and working memory.

CONCLUSIONS

In people with SCZ-CUD, a modest single dose of oral THC was associated with worse cognitive functioning without symptom exacerbation several hours after administration, and a THC dose-response effect was seen for negative symptoms.

Hot and Cool Executive Function in Children with Autism Spectrum Disorder and Schizotypal Traits

Background: Schizotypal traits are notably prevalent among children diagnosed with Autism spectrum disorder (ASD). Both conditions commonly exhibit impairments in executive functions (EF), which encompass cool and hot processes. The observed deficits in these EF domains across ASD and schizotypy underscore a compelling need to investigate how their co-occurrence impacts EF. Methods: This study investigated the impact of co-occurring autistic and schizotypal traits on EF in 63 children diagnosed with ASD, aged 7 to 12 years. Participants were assessed using the Autism Diagnostic Observation Schedule-2 (ADOS-2), the Melbourne Assessment of Schizotypy in Kids (MASK), and a battery of hot and cool EF tests. Results: Correlational analyses revealed a significant association between MASK score and working memory, as well as between ADOS scores and various cool EF components (i.e., working memory, inhibition and planning). Hierarchical regression analyses showed that the interaction between ADOS and MASK scores significantly predicted performance on hot EF (i.e., affective decision-making), but not on cool EF tasks. Conclusions: These findings suggest that the co-occurrence of ASD and schizotypal traits may have differential effects on cool and hot EF domains. Understanding how the combination of autistic and schizotypal traits affects cognitive processes may inform tailored interventions and support strategies for individuals presenting with these traits.

The Relationship Among Range Adaptation, Social Anhedonia, and Social Functioning: A Combined Magnetic Resonance Spectroscopy and Resting-State fMRI Study

BACKGROUND AND HYPOTHESIS

Social anhedonia is a core feature of schizotypy and correlates significantly with social functioning and range adaptation. Range adaptation refers to representing a stimulus value based on its relative position in the range of pre-experienced values. This study aimed to examine the resting-state neural correlates of range adaptation and its associations with social anhedonia and social functioning.

STUDY DESIGN

In study 1, 60 participants completed resting-state magnetic resonance spectroscopy and fMRI scans. Range adaptation was assessed by a valid effort-based decision-making paradigm. Self-reported questionnaires was used to measure social anhedonia and social functioning. Study 2 utilized 26 pairs of participants with high (HSoA) and low levels of social anhedonia (LSoA) to examine the group difference in range adaptation's neural correlates and its relationship with social anhedonia and social functioning. An independent sample of 40 pairs of HSoA and LSoA was used to verify the findings.

STUDY RESULTS

Study 1 showed that range adaptation correlated with excitation-inhibition balance (EIB) and ventral prefrontal cortex (vPFC) functional connectivity, which in turn correlating positively with social functioning. Range adaptation was specifically determined by the EIB via mediation of ventral-medial prefrontal cortex functional connectivities. Study 2 found HSoA and LSoA participants exhibiting comparable EIB and vPFC connectivities. However, EIB and vPFC connectivities were negatively correlated with social anhedonia and social functioning in HSoA participants.

CONCLUSIONS

EIB and vPFC functional connectivity is putative neural correlates for range adaptation. Such neural correlates are associated with social anhedonia and social functioning.

The Relationship Between Schizotypal Personality Traits and Temporal Discounting: The Role of the Date/Delay Effect

BACKGROUND AND HYPOTHESIS

Many patients with psychiatric disorders show increased temporal discounting (TD), ie, they discount future rewards more steeply than healthy controls. However, findings for schizophrenia and schizotypy, a personality constellation considered to be on the schizophrenia spectcrum, are less clear. Moreover, the role of future time representation in TD in the schizophrenia spectrum has not been examined. We hypothesized positive associations between schizotypal personality traits and TD and reduced TD when the timepoint of future rewards is represented in dates rather than delay units (the date/delay effect). Further, we explored associations between schizotypy and the magnitude of the date/delay effect.

STUDY DESIGN

We conducted a large-scale, general-population online study (N = 1000) assessing TD with the Monetary Choice Questionnaire (MCQ) and schizotypal traits with the Short Oxford-Liverpool Inventory of Feelings and Experiences (sO-LIFE). Time representation in the MCQ (dates vs delays) was manipulated within subject.

STUDY RESULTS

Associations between TD and sO-LIFE subscales were not significant after Bonferroni correction (all r ≤ .06). The date/delay effect was successfully replicated (P < .001, gav = 0.22). Interestingly, higher values in the sO-LIFE Unusual Experiences subscale predicted the magnitude of the date/delay effect when controlling for influences of other sO-LIFE subscales, age, education, and drug use.

CONCLUSIONS

TD was not associated with schizotypy, but individuals with higher levels of positive schizotypy were more sensitive to manipulations of the representation of future timepoints. Future studies should focus on these processes as potential mechanisms in the development and treatment of cognitive-perceptual deficits in the schizophrenia spectrum.

A network approach exploring the effects of cognitive remediation on cognition, symptoms, and functioning in early psychosis

BACKGROUND

Although cognitive remediation (CR) improves cognition and functioning, the key features that promote or inhibit its effectiveness, especially between cognitive domains, remain unknown. Discovering these key features will help to develop CR for more impact.

AIM

To identify interrelations between cognition, symptoms, and functioning, using a novel network analysis approach and how CR affects these recovery outcomes.

METHODS

A secondary analysis of randomized controlled trial data (N = 165) of CR in early psychosis. Regularized partial correlation networks were estimated, including symptoms, cognition, and functioning, for pre-, post-treatment, and change over time. Pre- and post-CR networks were compared on global strength, structure, edge invariance, and centrality invariance.

RESULTS

Cognition, negative, and positive symptoms were separable constructs, with symptoms showing independent relationships with cognition. Negative symptoms were central to the CR networks and most strongly associated with change in functioning. Verbal and visual learning improvement showed independent relationships to improved social functioning and negative symptoms. Only visual learning improvement was positively associated with personal goal achievement. Pre- and post-CR networks did not differ in structure (M = 0.20, p = 0.45) but differed in global strength, reflecting greater overall connectivity in the post-CR network (S = 0.91, p = 0.03).

CONCLUSIONS

Negative symptoms influenced network changes following therapy, and their reduction was linked to improvement in verbal and visual learning following CR. Independent relationships between visual and verbal learning and functioning suggest that they may be key intervention targets to enhance social and occupational functioning.

Altered neural signalling during reward anticipation in children and early adolescents with high psychotic-like experiences

BACKGROUND

Schizophrenia is associated with abnormalities in neurodevelopmental processes. Furthermore, dysfunctional neural circuits involved in reward processing may be linked to the development of symptoms in schizophrenia and are predictive of long-term functional outcome. It is however unknown whether neural signatures of reward anticipation are detectable in children with high psychotic-like experiences.

METHODS

Using data from the ABCD study 4.1, we defined a healthy control (N = 50) and a high psychotic-like experience (N = 50) group with a Prodromal Psychosis Syndrome (PPS) score > 3 and distress score > 6 at baseline (9-10 years) and 2nd year follow-up (11-12 years). While undergoing functional MR-imaging, all children completed the Monetary Incentive Delay task. Using the preprocessed ABCD-data, we explored whether behaviour and brain activations for reward and loss anticipation in areas underlying reward processing differed between groups and time-points. Furthermore, we investigated whether those brain activations that showed differences between the groups were predictive of later PPS scores. Additionally, we also employed computational modelling to assess response vigour.

RESULTS

While response times did not differ, the computational model revealed that response vigour for salient cues was significantly lower in the high PLEs compared to controls at baseline. We also found that children with high PLEs demonstrated lower activation during reward anticipation in the anterior insula at the baseline time-point; the nucleus accumbens, the putamen, the dorsolateral (dlPFC) and the ventral medial prefrontal cortex at the 2nd year follow-up, and in the caudate at both timepoints, compared to controls. Regression analysis revealed that deactivations in the left anterior insula and left dlPFC, was predictive of later PPS scores.

CONCLUSION

This study reveals that neural alterations during reward anticipation are detectable in children with high PLEs. These dysfunctions in neural activation patterns may serve as potential predictive biomarkers for psychosis.

A generalized reward processing deficit pathway to negative symptoms across diagnostic boundaries

BACKGROUND

Negative symptoms are a key feature of several psychiatric disorders. Difficulty identifying common neurobiological mechanisms that cut across diagnostic boundaries might result from equifinality (i.e., multiple mechanistic pathways to the same clinical profile), both within and across disorders. This study used a data-driven approach to identify unique subgroups of participants with distinct reward processing profiles to determine which profiles predicted negative symptoms.

METHODS

Participants were a transdiagnostic sample of youth from a multisite study of psychosis risk, including 110 individuals at clinical high-risk for psychosis (CHR; meeting psychosis-risk syndrome criteria), 88 help-seeking participants who failed to meet CHR criteria and/or who presented with other psychiatric diagnoses, and a reference group of 66 healthy controls. Participants completed clinical interviews and behavioral tasks assessing four reward processing constructs indexed by the RDoC Positive Valence Systems: hedonic reactivity, reinforcement learning, value representation, and effort-cost computation.

RESULTS

k-means cluster analysis of clinical participants identified three subgroups with distinct reward processing profiles, primarily characterized by: a value representation deficit (54%), a generalized reward processing deficit (17%), and a hedonic reactivity deficit (29%). Clusters did not differ in rates of clinical group membership or psychiatric diagnoses. Elevated negative symptoms were only present in the generalized deficit cluster, which also displayed greater functional impairment and higher psychosis conversion probability scores.

CONCLUSIONS

Contrary to the equifinality hypothesis, results suggested one global reward processing deficit pathway to negative symptoms independent of diagnostic classification. Assessment of reward processing profiles may have utility for individualized clinical prediction and treatment.

Modeling Decision-Making in Schizophrenia: Associations Between Computationally Derived Risk Propensity and Self-Reported Risk Perception

BACKGROUND AND HYPOTHESIS

Schizophrenia is associated with a decreased pursuit of risky rewards during uncertain-risk decision-making. However, putative mechanisms subserving this disadvantageous risky reward pursuit, such as contributions of cognition and relevant traits, remain poorly understood.

STUDY DESIGN

Participants (30 schizophrenia/schizoaffective disorder [SZ]; 30 comparison participants [CP]) completed the Balloon Analogue Risk Task (BART). Computational modeling captured subprocesses of uncertain-risk decision-making: Risk Propensity, Prior Belief of Success, Learning Rate, and Behavioral Consistency. IQ, self-reported risk-specific processes (ie, Perceived Risks and Expected Benefit of Risks), and non-risk-specific traits (ie, defeatist beliefs; hedonic tone) were examined for relationships with Risk Propensity to determine what contributed to differences in risky reward pursuit.

STUDY RESULTS

On the BART, the SZ group exhibited lower Risk Propensity, higher Prior Beliefs of Success, and comparable Learning Rates. Furthermore, Risk Propensity was positively associated with IQ across groups. Linear models predicting Risk Propensity revealed 2 interactions: 1 between group and Perceived Risk, and 1 between IQ and Perceived Risk. Specifically, in both the SZ group and individuals with below median IQ, lower Perceived Risks was related to lower Risk Propensity. Thus, lower perception of financial risks was associated with a less advantageous pursuit of uncertain-risk rewards.

CONCLUSIONS

Findings suggest consistently decreased risk-taking on the BART in SZ may reflect risk imperception, the failure to accurately perceive and leverage relevant information to guide the advantageous pursuit of risky rewards. Additionally, our results highlight the importance of cognition in uncertain-risk decision-making.

Dynamic Changes in Chloride Homeostasis Coordinate Midbrain Inhibitory Network Activity during Reward Learning

The ability to associate environmental stimuli with positive outcomes is a fundamental form of learning. While extensive research has focused on the response profiles of midbrain dopamine neurons during associative learning, less is known about learning-mediated changes in the afferents that shape their responses. We demonstrate that during critical phases of learning, anion homeostasis in midbrain GABA neurons - a primary source of input to dopamine neurons - is disrupted due to downregulation of the chloride transporter KCC2. This alteration in GABA neurons preferentially impacted lateral mesoaccumbal dopamine pathways and was not observed after learning was established. At the network level, learning-mediated KCC2 downregulation was associated with enhanced synchronization between individual GABA neurons and increased dopamine responses to reward-related stimuli. Conversely, enhancing KCC2 function during learning reduced GABA synchronization, diminished relevant dopamine signaling, and prevented cue-reward associations. Thus, circuit-specific adaptations in midbrain GABA neurons are crucial for forming new reward-related behaviors.

Understanding the Mechanisms of Cognitive Remediation on Recovery in People With Early Psychosis: A Mediation and Moderation Analysis

BACKGROUND

To provide precision cognitive remediation therapy (CR) for schizophrenia, we need to understand whether the mechanism for improved functioning is via cognition improvements. This mechanism has not been rigorously tested for potential moderator effects.

STUDY DESIGN

We used data (n = 377) from a randomized controlled trial using CIRCuiTS, a therapist-supported CR, with participants from first-episode psychosis services. We applied structured equation modeling to test whether: (1) CR hours explain the goal attainment functional outcome (GAS) at posttreatment, (2) global cognitive improvement mediates GAS, and if (3) total symptoms moderate the CR hours to cognitive improvement pathway, and/or negative symptoms moderate the cognition to functioning pathway, testing moderator effects via the mediator or directly on CR hours to functioning path.

STUDY RESULTS

CR produced significant functioning benefit for each therapy hour (Coeff = 0.203, 95% CI 0.101-0.304, P < .001). The mediated path from CR hours to cognition and cognition to functioning was small and nonsignificant (Coeff = 0.014, 95% CI = -0.010, 0.037, P = .256). Total symptoms did not moderate the path to cognition (P = .211) or the direct path to outcome (P = .896). However, negative symptoms significantly moderated the effect of cognitive improvements on functioning (P = .015) with high negative symptoms reducing the functional gains of improved cognition.

CONCLUSIONS

Although cognitive improvements were correlated with functioning benefit, they did not fully explain the positive effect of increased therapy hours on functioning, suggesting additional CR factors also contribute to therapy benefit. Negative symptoms interfere with the translation of cognitive improvements into functional gains so need consideration.

The Effects of Cognitive Remediation on Negative Symptoms in Schizophrenia-Spectrum Illness: A Meta-analytic Investigation of Efficacy

BACKGROUND AND HYPOTHESIS

The number of clinical efficacy trials of Cognitive Remediation (CR), a behavioral intervention consisting of cognitive task practice and/or strategy training to improve cognitive skills in schizophrenia, has increased substantially over the past 25 years. While recent reviews have highlighted the effects of CR on cognition and function, CR effects on negative symptoms remain understudied. Given the overlap between negative symptoms and cognition, CR effects might be expected.

STUDY DESIGN

Electronic databases were evaluated up to September 2023 using a broad range of search terms. Sixty-nine unique, controlled trials that used negative symptoms as an outcome were meta-analyzed. Data were independently extracted with excellent (>98%) reliability. Random effects models assessed the effects of CR on summary and expressive vs. experiential negative symptoms. Moderator analyses evaluated a broad array of treatment and participant factors.

STUDY RESULTS

The meta-analysis (5319 participants) revealed that CR produced a small effect size improvement on summary negative symptoms (Hedge's g = 0.179). Sample differences in age, duration of illness, symptoms, and antipsychotic dosage did not serve as a barrier to treatment benefit. CR also produced small-to-moderate improvements in alogia (Hedge's g = 0.312) but not experiential negative symptoms. Programs of CR that utilized bridging activities that relate training of cognitive skills to activities of daily living produced greater improvement in negative symptoms (g = 0.281 vs 0.055). Longer CR programs also produce larger effects on negative symptoms.

CONCLUSIONS

CR produces small, consistent reductions in negative symptoms in people with schizophrenia. Variations in CR effects may be linked to different treatment ingredients.

Global reward processing deficits predict negative symptoms transdiagnostically and transphasically in a severe mental illness-spectrum sample

Reward processing impairments are a key factor associated with negative symptoms in those with severe mental illnesses. However, past findings are inconsistent regarding which reward processing components are impaired and most strongly linked to negative symptoms. The current study examined the hypothesis that these mixed findings may be the result of multiple reward processing pathways (i.e., equifinality) to negative symptoms that cut across diagnostic boundaries and phases of illness. Participants included healthy controls (n = 100) who served as a reference sample and a severe mental illness-spectrum sample (n = 92) that included psychotic-like experiences, clinical high-risk for psychosis, bipolar disorder, and schizophrenia participants. All participants completed tasks measuring four RDoC Positive Valence System constructs: value representation, reinforcement learning, effort-cost computation, and hedonic reactivity. A k-means cluster analysis of the severe mental illness-spectrum samples identified three clusters with differential reward processing profiles that were characterized by: (1) global reward processing deficits (22.8%), (2) selective impairments in hedonic reactivity alone (40.2%), and (3) preserved reward processing (37%). Elevated negative symptoms were only observed in the global reward processing cluster. All clusters contained participants from each clinical group, and the distribution of these groups did not significantly differ among the clusters. Findings identified one pathway contributing to negative symptoms that was transdiagnostic and transphasic. Future work further characterizing divergent pathways to negative symptoms may help to improve symptom trajectories and personalized treatments.

Personalized Cognitive Health in Psychiatry: Current State and the Promise of Computational Methods

BACKGROUND

Decades of research have firmly established that cognitive health and cognitive treatment services are a key need for people living with psychosis. However, many current clinical programs do not address this need, despite the essential role that an individual's cognitive and social cognitive capacities play in determining their real-world functioning. Preliminary practice-based research in the Early Psychosis Intervention Network early psychosis intervention network shows that it is possible to develop and implement tools that delineate an individuals' cognitive health profile and that help engage the client and the clinician in shared decision-making and treatment planning that includes cognitive treatments. These findings signify a promising shift toward personalized cognitive health.

STUDY DESIGN

Extending upon this early progress, we review the concept of interindividual variability in cognitive domains/processes in psychosis as the basis for offering personalized treatment plans. We present evidence from studies that have used traditional neuropsychological measures as well as findings from emerging computational studies that leverage trial-by-trial behavior data to illuminate the different latent strategies that individuals employ.

STUDY RESULT

We posit that these computational techniques, when combined with traditional cognitive assessments, can enrich our understanding of individual differences in treatment needs, which in turn can guide evermore personalized interventions.

CONCLUSION

As we find clinically relevant ways to decompose maladaptive behaviors into separate latent cognitive elements captured by model parameters, the ultimate goal is to develop and implement approaches that empower clients and their clinical providers to leverage individual's existing learning capacities to improve their cognitive health and well-being.

Towards New Methodology for Cross-Validation of Clinical Evaluation Scales and Functional MRI in Psychiatry

Objective biomarkers have been a critical challenge for the field of psychiatry, where diagnostic, prognostic, and theranostic assessments are still based on subjective narratives. Psychopathology operates with idiographic knowledge and subjective evaluations incorporated into clinical assessment inventories, but is considered to be a medical discipline and, as such, uses medical intervention methods (e.g., pharmacological, ECT; rTMS; tDCS) and, therefore, is supposed to operate with the language and methods of nomothetic networks. The idiographic assessments are provisionally "quantified" into "structured clinical scales" to in some way resemble nomothetic measures. Instead of fostering data merging and integration, this approach further encapsulates the clinical psychiatric methods, as all other biological tests (molecular, neuroimaging) are performed separately, only after the clinical assessment has provided diagnosis. Translational cross-validation of clinical assessment instruments and fMRI is an attempt to address the gap. The aim of this approach is to investigate whether there exist common and specific neural circuits, which underpin differential item responses to clinical self-rating scales during fMRI sessions in patients suffering from the two main spectra of mental disorders: schizophrenia and major depression. The current status of this research program and future implications to promote the development of psychiatry as a medical discipline are discussed.

Electrophysiological Correlates of Reward Anticipation in Subjects with Schizophrenia: An ERP Microstate Study

The current study aimed to investigate alterations of event-related potentials (ERPs) microstate during reward anticipation in subjects with schizophrenia (SCZ), and their association with hedonic experience and negative symptoms. EEG data were recorded in thirty SCZ and twenty-three healthy controls (HC) during the monetary incentive delay task in which reward, loss and neutral cues were presented. Microstate analysis and standardized low-resolution electromagnetic tomography (sLORETA) were applied to EEG data. Furthermore, analyses correlating a topographic index (the ERPs score), calculated to quantify brain activation in relationship to the microstate maps, and scales assessing hedonic experience and negative symptoms were performed. Alterations in the first (125.0-187.5 ms) and second (261.7-414.1 ms) anticipatory cue-related microstate classes were observed. In SCZ, reward cues were associated to shorter duration and earlier offset of the first microstate class as compared to the neutral condition. In the second microstate class, the area under the curve was smaller for both reward and loss anticipation cues in SCZ as compared to HC. Furthermore, significant correlations between ERPs scores and the anticipation of pleasure scores were detected, while no significant association was found with negative symptoms. sLORETA analysis showed that hypo-activation of the cingulate cortex, insula, orbitofrontal and parietal cortex was detected in SCZ as compared to HC. Abnormalities in ERPs could be traced already during the early stages of reward processing and were associated with the anticipation of pleasure, suggesting that these dysfunctions might impair effective evaluation of incoming pleasant experiences. Negative symptoms and anhedonia are partially independent results.

Contingency Management for Dually Diagnosed Inpatients with Psychosis

Contingency management (CM) is an evidence-based treatment method in substance abuse treatment. However, little is known about its efficacy in dually diagnosed patients with psychosis and in inpatient settings. Therefore, the aim of this study is to investigate the efficacy of CM for dually diagnosed patients with psychosis in an inpatient setting. Furthermore, we investigate the effect of the nature of the reward used (cash vs. prize) on the efficacy of CM. We made use of an 8-week fish-bowl CM intervention by means of a within-subject reversal design with three treatment phases (baseline-intervention-follow-up). Sixty-seven patients were included in this study, of whom thirty-four completed the protocol. The results show no effect of CM on abstinence nor an interaction with clinical or demographic variables. Cash money is as effective as prizes. Future research should further investigate the effect of psychosis and treatment setting on the efficacy of CM, with special attention for Patient Report Experience and Outcome Measures (PREM/PROM).

Pupillary responses as a biomarker of cognitive effort and the impact of task difficulty on reward processing in schizophrenia

Negative symptoms of schizophrenia robustly predict functional outcomes but remain relatively resistant to available treatments. Better measures of negative symptoms, especially motivational deficits, are needed to better understand these symptoms and improve treatment development. Recent research shows promise in linking behavioral effort tasks to motivational negative symptoms, reward processing deficits, and defeatist attitudes, but few studies account for individual or group (patient v. control) differences in cognitive ability to perform the tasks. Individuals with poorer abilities might be less motivated to perform tasks because they find them more difficult to perform. This study used a personalized digit span task to control task difficulty while measuring task effort via pupillary responses (greater dilation indicates greater cognitive effort) at varying monetary rewards ($1 & $2). Participants with schizophrenia (N = 34) and healthy controls (N = 41) performed a digit span task with personalized max span lengths and easy (max- 2 digits) and overload (max+ 2 digits) conditions. Consistent with many studies, pupillary responses (cognitive effort) increased with greater difficulty until exceeding capacity. A similar pattern of reward responsivity was seen in both groups, such that greater reward increased dilation (effort) comparably for both groups when difficulty was within capacity. Neither patients nor controls exerted increased effort for greater reward when difficulty exceeded capacity. In patients, positive relationships were found between pupil dilation and defeatist performance beliefs if task difficulty was within capacity; a relationship that reversed if the task was too difficult. The findings demonstrate the importance of accounting for cognitive capacity and task difficulty when evaluating motivation and reward sensitivity and illustrate the utility of pupillary responses as an objective measure of effort in schizophrenia.

Associative learning and facial expression recognition in schizophrenic patients: Effects of social presence

Schizophrenia (SCZ) is a psychiatric disorder that alters both general and social cognition. However, the exact mechanisms that are altered remain to be elucidated. In this study, we investigated associative learning (AL) and facial expression recognition (FER) in the same patients, using emotional expressions and abstract images. Our main aim was to investigate how these cognitive abilities are affected by SCZ and to assess the role of mere social presence, a factor that has not been considered before. The study compared the behavioral performance of 60 treated outpatients with SCZ and 103 demographically matched healthy volunteers. In the AL task, participants had to associate abstract images or facial expressions with key presses, guided by feedback on each trial. In the FER task, they had to report whether two successively presented facial expressions were the same or different. All participants performed the two tasks under two social context conditions: alone or in the presence of a passive but attentive audience. The results showed a severe learning impairment in patients compared to controls, with a slight advantage for facial expressions compared to abstract images, and a gender-dependent effect of social presence. In contrast, facial expression recognition was partially spared in patients and facilitated by social presence. We conclude that cognitive abilities are impaired in patients with SCZ, but their investigation needs to take into account the social context in which they are assessed.

Reward Learning as a Potential Mechanism for Improvement in Schizophrenia Spectrum Disorders Following Cognitive Remediation: Protocol for a Clinical, Nonrandomized, Pre-Post Pilot Study

BACKGROUND

Cognitive impairment is common with schizophrenia spectrum disorders. Cognitive remediation (CR) is effective in improving global cognition, but not all individuals benefit from this type of intervention. A better understanding of the potential mechanism of action of CR is needed. One proposed mechanism is reward learning (RL), the cognitive processes responsible for adapting behavior following positive or negative feedback. It is proposed that the structure of CR enhances RL and motivation to engage in increasingly challenging tasks, and this is a potential mechanism by which CR improves cognitive functioning in schizophrenia.

OBJECTIVE

Our primary objective is to examine reward processing in individuals with schizophrenia before and after completing CR and to compare this with a group of matched clinical controls. We will assess whether RL mediates the relationship between CR and improved cognitive function and reduced negative symptoms. Potential differences in social RL and nonsocial RL in individuals with schizophrenia will also be investigated and compared with a healthy matched control group.

METHODS

We propose a clinical, nonrandomized, pre-post pilot study comparing the impact of CR on RL and neurocognitive outcomes. The study will use a combination of objective and subjective measures to assess neurocognitive, psychiatric symptoms, and neurophysiological domains. A total of 40 individuals with schizophrenia spectrum disorders (aged 18-35 years) will receive 12 weeks of CR therapy (n=20) or treatment as usual (n=20). Reward processing will be evaluated using a reinforcement learning task with 2 conditions (social reward vs nonsocial reward) at baseline and the 12-week follow-up. Functional magnetic resonance imaging responses will be measured during this task. To validate the reinforcement learning task, RL will also be assessed in 20 healthy controls, matched for age, sex, and premorbid functioning. Mixed-factorial ANOVAs will be conducted to evaluate treatment group differences. For the functional magnetic resonance imaging analysis, computational modeling will allow the estimation of learning parameters at each point in time, during each task condition, for each participant. We will use a variational Bayesian framework to measure how learning occurred during the experimental task and the subprocesses that underlie this learning. Second-level group analyses will examine how learning in patients differs from that observed in control participants and how CR alters learning efficiency and the underlying neural activity.

RESULTS

As of September 2023, this study has enrolled 15 participants in the CR group, 1 participant in the treatment-as-usual group, and 11 participants in the healthy control group. Recruitment is expected to be completed by September 2024. Data analysis is expected to be completed and published in early 2025.

CONCLUSIONS

The results of this study will contribute to the knowledge of CR and RL processes in severe mental illness and the understanding of the systems that impact negative symptoms and cognitive impairments within this population.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/52505.

Transdiagnostic inflexible learning dynamics explain deficits in depression and schizophrenia

Deficits in reward learning are core symptoms across many mental disorders. Recent work suggests that such learning impairments arise by a diminished ability to use reward history to guide behaviour, but the neuro-computational mechanisms through which these impairments emerge remain unclear. Moreover, limited work has taken a transdiagnostic approach to investigate whether the psychological and neural mechanisms that give rise to learning deficits are shared across forms of psychopathology. To provide insight into this issue, we explored probabilistic reward learning in patients diagnosed with major depressive disorder (n = 33) or schizophrenia (n = 24) and 33 matched healthy controls by combining computational modelling and single-trial EEG regression. In our task, participants had to integrate the reward history of a stimulus to decide whether it is worthwhile to gamble on it. Adaptive learning in this task is achieved through dynamic learning rates that are maximal on the first encounters with a given stimulus and decay with increasing stimulus repetitions. Hence, over the course of learning, choice preferences would ideally stabilize and be less susceptible to misleading information. We show evidence of reduced learning dynamics, whereby both patient groups demonstrated hypersensitive learning (i.e. less decaying learning rates), rendering their choices more susceptible to misleading feedback. Moreover, there was a schizophrenia-specific approach bias and a depression-specific heightened sensitivity to disconfirmational feedback (factual losses and counterfactual wins). The inflexible learning in both patient groups was accompanied by altered neural processing, including no tracking of expected values in either patient group. Taken together, our results thus provide evidence that reduced trial-by-trial learning dynamics reflect a convergent deficit across depression and schizophrenia. Moreover, we identified disorder distinct learning deficits.

The relationship between negative symptoms and MATRICS neurocognitive domains: A meta-analysis and systematic review

BACKGROUND

Negative symptoms (NS) are a core symptom domain in schizophrenia spectrum disorders and are associated with poorer social and vocational functioning, and with increased likelihood and durations of hospital admission. NS are not well understood, limiting available interventions. However, numerous studies have reported associations between neurocognitive domains and NS severity. Thus, one promising area in understanding NS is in relation to neurocognition. Currently, the specificity of the relationship between NS and neurocognition is unknown, meaning that there is no consensus regarding which neurocognitive domain is most strongly associated with NS. There is a need to systematically examine the relationship between NS and various neurocognitive domains within study samples.

METHODS

A systematic search of Ovid PsycINFO, Ovid MEDLINE and Web of Science was performed for articles published since 2004 (year of MATRICS Consensus publication). Inclusion criteria were: 1) individuals with schizophrenia spectrum disorders, first episode psychosis or clinical high risk 2) assessed all six MATRICS neurocognitive domains (processing speed, attention, working memory, verbal learning & memory, visual learning & memory, reasoning & problem solving), 3) reported correlations between all six MATRICS neurocognitive domains and global NS. A three-level random effects hierarchical meta-analysis was performed to assess the relationship between NS (global, expressive, and experiential dimensions) and the six MATRICS neurocognitive domains.

RESULTS

21 studies were included in the review (n = 3619). All MATRICS neurocognitive domains had small significant correlations with global NS (r = -0.16 to -0.20, p < 0.0001). This relationship was significantly moderated by diagnosis and the moderating effect of sex/ gender trended on significance. Analysis of a subset of the studies revealed that MATRICS neurocognitive domains also had small significant correlations with the two NS dimensions, expressive and experiential. Correlations were stronger with the expressive NS dimension.

CONCLUSIONS

This review is novel in assessing the relationship between multiple neurocognitive domains and NS within the same sample, by synthesizing close to two decades of research. Our results suggest that there is a non-specific relationship between neurocognition and NS, and that expressive NS may have a stronger relationship with neurocognitive functioning-based on the MATRICS classification of neurocognition and the neurocognitive assessments used in the included studies. This has implications on our understanding of NS and neurocognition, as well as their treatments. As we gain better understanding of the directionality of the NS-cognition relationship, it could suggest that NS, particularly in the expressive domain, could be improved by targeting cognition globally or that neurocognitive treatments could be more effective if NS are addressed first. Further implications of these results are discussed.

Revisiting reward impairments in schizophrenia spectrum disorders: a systematic review and meta-analysis for neuroimaging findings

BACKGROUND

Abnormal reward functioning is central to anhedonia and amotivation symptoms of schizophrenia (SCZ). Reward processing encompasses a series of psychological components. This systematic review and meta-analysis examined the brain dysfunction related to reward processing of individuals with SCZ spectrum disorders and risks, covering multiple reward components.

METHODS

After a systematic literature search, 37 neuroimaging studies were identified and divided into four groups based on their target psychology components (i.e. reward anticipation, reward consumption, reward learning, effort computation). Whole-brain Seed-based d Mapping (SDM) meta-analyses were conducted for all included studies and each component.

RESULTS

The meta-analysis for all reward-related studies revealed reduced functional activation across the SCZ spectrum in the striatum, orbital frontal cortex, cingulate cortex, and cerebellar areas. Meanwhile, distinct abnormal patterns were found for reward anticipation (decreased activation of the cingulate cortex and striatum), reward consumption (decreased activation of cerebellum IV/V areas, insula and inferior frontal gyri), and reward learning processing (decreased activation of the striatum, thalamus, cerebellar Crus I, cingulate cortex, orbitofrontal cortex, and parietal and occipital areas). Lastly, our qualitative review suggested that decreased activation of the ventral striatum and anterior cingulate cortex was also involved in effort computation.

CONCLUSIONS

These results provide deep insights on the component-based neuro-psychopathological mechanisms for anhedonia and amotivation symptoms of the SCZ spectrum.

The positivity offset theory of anhedonia in schizophrenia: evidence for a deficit in daily life using digital phenotyping

BACKGROUND

Negative symptoms of schizophrenia have recently been proposed to result from a decoupling of (intact) hedonic experience and (diminished) approach behavior. The current study challenged this view by exploring the hypothesis that negative symptoms are driven by a specific type of emotional experience abnormality, a reduction in the positivity offset (i.e. the tendency to experience greater levels of positive relative to negative emotion in low-arousal contexts), which limits the production of approach behaviors in neutral environments.

METHODS

Participants included outpatients with SZ (n = 44) and healthy controls (CN: n = 48) who completed one week of active (ecological momentary assessment surveys of emotional experience and symptoms) and passive (geolocation, accelerometry) digital phenotyping. Mathematical modeling approaches from Cacioppo's Evaluative Space Model were used to quantify the positivity offset in daily life. Negative symptoms were assessed via standard clinical ratings, as well as active (EMA surveys) and passive (geolocation, accelerometry) digital phenotyping measures.

RESULTS

Results indicated that the positivity offset was reduced in SZ and associated with more severe anhedonia and avolition measured via clinical interviews and active and passive digital phenotyping.

CONCLUSIONS

These findings suggest that current conceptual models of negative symptoms, which assume hedonic normality, may need to be revised to account for reductions in the positivity offset and its connection to diminished motivated behavior. Findings identify key real-world contexts where negative symptoms could be targeted using psychosocial treatments.

Regional cerebral blood flow at rest in schizophrenia and major depressive disorder: A functional neuroimaging meta-analysis

Severe mental disorders (SMDs) such as schizophrenia (SCZ), major depressive disorder (MDD) and bipolar disorder (BD) are associated with altered brain function. Neuroimaging studies have illustrated spontaneous activity alterations across SMDs, but no meta-analysis has directly compared resting-state regional cerebral blood flow (rCBF) with one another. We conducted a meta-analysis of PET, SPECT and ASL neuroimaging studies to identify specific alterations of rCBF at rest in SMDs. Included are 20 studies in MDD, and 18 studies in SCZ. Due to the insufficient number of studies in BD, this disorder was left out of the analyses. Compared to controls, the SCZ group displayed reduced rCBF in the triangular part of the left inferior frontal gyrus and in the medial orbital part of the bilateral superior frontal gyrus. After correction, only a small cluster in the right inferior frontal gyrus exhibited reduced rCBF in MDD, compared to controls. Differences were found in these brain regions between SCZ and MDD. SCZ displayed reduced rCBF at rest in regions associated with default-mode, reward processing and language processing. MDD was associated with reduced rCBF in a cluster involved in response inhibition. Our meta-analysis highlights differences in the resting-state rCBF alterations between SCZ and MDD.

A computational neuroimaging study of reinforcement learning and goal-directed exploration in schizophrenia spectrum disorders

BACKGROUND

Prior evidence indicates that negative symptom severity and cognitive deficits, in people with schizophrenia (PSZ), relate to measures of reward-seeking and loss-avoidance behavior (implicating the ventral striatum/VS), as well as uncertainty-driven exploration (reliant on rostrolateral prefrontal cortex/rlPFC). While neural correlates of reward-seeking and loss-avoidance have been examined in PSZ, neural correlates of uncertainty-driven exploration have not. Understanding neural correlates of uncertainty-driven exploration is an important next step that could reveal insights to how this mechanism of cognitive and negative symptoms manifest at a neural level.

METHODS

We acquired fMRI data from 29 PSZ and 36 controls performing the Temporal Utility Integration decision-making task. Computational analyses estimated parameters corresponding to learning rates for both positive and negative reward prediction errors (RPEs) and the degree to which participates relied on representations of relative uncertainty. Trial-wise estimates of expected value, certainty, and RPEs were generated to model fMRI data.

RESULTS

Behaviorally, PSZ demonstrated reduced reward-seeking behavior compared to controls, and negative symptoms were positively correlated with loss-avoidance behavior. This finding of a bias toward loss avoidance learning in PSZ is consistent with previous work. Surprisingly, neither behavioral measures of exploration nor neural correlates of uncertainty in the rlPFC differed significantly between groups. However, we showed that trial-wise estimates of relative uncertainty in the rlPFC distinguished participants who engaged in exploratory behavior from those who did not. rlPFC activation was positively associated with intellectual function.

CONCLUSIONS

These results further elucidate the nature of reinforcement learning and decision-making in PSZ and healthy volunteers.

Evidence for functional improvement in reward anticipation in recent onset schizophrenia after one year of coordinated specialty care

BACKGROUND

Motivational impairment associated with deficits in processing the anticipation of future reward is hypothesized to be a cardinal feature of schizophrenia spectrum disorders (SZ). Evidence from short-term follow-up (6-week post-treatment) studies suggests that these deficits may improve or be reversed with treatment, although longer-term outcomes are unknown. Here we examined the one-year trajectory of functional activation in brain circuitry associated with reward anticipation in people with recent onset SZ who participated in coordinated specialty care (CSC) treatment, hypothesizing normalization of brain response mirroring previous short-term findings in first-episode individuals.

METHOD

Blood oxygen level-dependent (BOLD) response in the dorsal anterior cingulate cortex, anterior insula, and ventral striatum (VS) associated with reward anticipation during the Incentivized Control Engagement Task (ICE-T) was analyzed in a baseline sample of 49 healthy controls (HCs) and 52 demographically matched people with SZ, with follow-up data available for 35 HCs and 17 people with SZ.

RESULTS

In agreement with our hypothesis, significant time × diagnosis interactions were observed across all regions, in which reward anticipation-associated BOLD response increased in SZ to above baseline HC levels at follow-up. Increased VS activation was associated with decreased reality distortion symptoms over the follow-up period. Baseline reward anticipation-associated BOLD response in the right anterior insula was associated with improvement in reality distortion symptoms.

CONCLUSIONS

These findings suggest that functional deficits in reward anticipation may be reversed after one year of CSC in recent onset participants with SZ, and that this improvement is associated with reduced positive symptoms in the illness.

Social Motivation in Schizophrenia: What's Effort Got to Do With It?

BACKGROUND AND HYPOTHESIS

Social motivation, defined as the fundamental human desire to seek out, engage in, and maintain interpersonal bonds, has become a growing area of research in schizophrenia. The major focus has been on understanding the impact of social reward-related processes. An obvious but rarely acknowledged fact is that social interactions, much like other goal-directed acts, require the exertion of effort. In this Review Article, we argue that social motivation in schizophrenia can be conceptualized through the lens of an established framework: effort-based decision-making (EBDM).

STUDY DESIGN

We conducted a literature review on social reward processing in schizophrenia, then extended these findings by applying concepts and insights from the literature on EBDM to the study of social motivation.

STUDY RESULTS

Within the EBDM framework, decisions about whether or not to pursue social interactions are bound by cost/benefit calculations. That is, people do not pursue social behaviors when the estimated "cost" of the required effort outweighs the anticipated "benefit" or reward. We propose that people with schizophrenia are less likely to engage in social interaction compared with healthy samples because they: (1) underestimate the benefits of relationships (based on expectations of reward/punishment), (2) overestimate the effort costs associated with social interaction, and/or (3) fail to integrate cost-benefit information in an optimal manner.

CONCLUSIONS

EBDM is an especially promising framework of social motivation that goes beyond the current focus on social reward processing to include a focus on effort.

Functional connectivity in a monetary and social incentive delay task in medicated patients with schizophrenia

Introduction

Numerous studies indicate impaired reward-related learning in individuals with schizophrenia, with various factors such as illness duration, medication, disease severity, and level of analysis (behavioral or neurophysiological data) potentially confounding the results. Patients with schizophrenia who are treated with second-generation antipsychotics have been found to have a less affected reward system. However, this finding does not explain the neural dysfunctions observed in previous studies. This study aimed to address the open question of whether the less impaired reward-related behavior is associated with unimpaired task-related functional connectivity or altered task-related functional connectivity.

Methods

The study included 23 participants diagnosed within the schizophrenia spectrum and 23 control participants matched in terms of age, sex, and education. Participants underwent an MRI while performing a monetary incentive delay task and a social incentive delay task. The collected data were analyzed in terms of behavior and functional connectivity.

Results

Both groups exhibited a main effect of reward type on behavioral performance, indicating faster reaction times in the social incentive delay task, but no main effect of reward level. Altered functional connectivity was observed in predictable brain regions within the patient group, depending on the chosen paradigm, but not when compared to healthy individuals.

Discussion

In addition to expected slower response times, patients with schizophrenia demonstrated similar response patterns to control participants at the behavioral level. The similarities in behavioral data may underlie different connectivity patterns. Our findings suggest that perturbations in reward processing do not necessarily imply disturbances in underlying connectivities. Consequently, we were able to demonstrate that patients with schizophrenia are indeed capable of exhibiting goal-directed, reward-responsive behavior, although there are differences depending on the type of reward.

Integrative Brain Network and Salience Models of Psychopathology and Cognitive Dysfunction in Schizophrenia

Brain network models of cognitive control are central to advancing our understanding of psychopathology and cognitive dysfunction in schizophrenia. This review examines the role of large-scale brain organization in schizophrenia, with a particular focus on a triple-network model of cognitive control and its role in aberrant salience processing. First, we provide an overview of the triple network involving the salience, frontoparietal, and default mode networks and highlight the central role of the insula-anchored salience network in the aberrant mapping of salient external and internal events in schizophrenia. We summarize the extensive evidence that has emerged from structural, neurochemical, and functional brain imaging studies for aberrancies in these networks and their dynamic temporal interactions in schizophrenia. Next, we consider the hypothesis that atypical striatal dopamine release results in misattribution of salience to irrelevant external stimuli and self-referential mental events. We propose an integrated triple-network salience-based model incorporating striatal dysfunction and sensitivity to perceptual and cognitive prediction errors in the insula node of the salience network and postulate that dysregulated dopamine modulation of salience network-centered processes contributes to the core clinical phenotype of schizophrenia. Thus, a powerful paradigm to characterize the neurobiology of schizophrenia emerges when we combine conceptual models of salience with large-scale cognitive control networks in a unified manner. We conclude by discussing potential therapeutic leads on restoring brain network dysfunction in schizophrenia.

Confidence, accuracy judgments and feedback in schizophrenia and bipolar disorder: a time series network analysis

BACKGROUND

Inaccurate self-assessment of performance is common among people with serious mental illness, and it is associated with poor functional outcomes independent from ability. However, the temporal interdependencies between judgments of performance, confidence in accuracy, and feedback about performance are not well understood.

METHODS

We evaluated two tasks: the Wisconsin Card Sorting Test (WCST) and the Penn Emotion recognition task (ER40). These tasks were modified to include item-by-item confidence and accuracy judgments, along with feedback on accuracy. We evaluated these tasks as time series and applied network modeling to understand the temporal relationships between momentary confidence, accuracy judgments, and feedback. The sample constituted participants with schizophrenia (SZ; N = 144), bipolar disorder (BD; N = 140), and healthy controls (HC; N = 39).

RESULTS

Network models for both WCST and ER40 revealed denser and lagged connections between confidence and accuracy judgments in SZ and, to a lesser extent in BD, that were not evidenced in HC. However, associations between feedback regarding accuracy with subsequent accuracy judgments and confidence were weaker in SZ and BD. In each of these comparisons, the BD group was intermediate between HC and SZ. In analyses of the WCST, wherein incorporating feedback is crucial for success, higher confidence predicted worse subsequent performance in SZ but not in HC or BD.

CONCLUSIONS

While network models are exploratory, the results suggest some potential mechanisms by which challenges in self-assessment may impede performance, perhaps through hyperfocus on self-generated judgments at the expense of incorporation of feedback.

Repeat investigation during social preference behavior is suppressed in male mice with prefrontal cortex cacna1c (Cav1.2)-deficiency through the dysregulation of neural dynamics

Impairments in social behavior are observed in a range of neuropsychiatric disorders and several lines of evidence have demonstrated that dysfunction of the prefrontal cortex (PFC) plays a central role in social deficits. We have previously shown that loss of neuropsychiatric risk gene Cacna1c that codes for the Cav1.2 isoform of L-type calcium channels (LTCCs) in the PFC result in impaired sociability as tested using the three-chamber social approach test. In this study we aimed to further characterize the nature of the social deficit associated with a reduction in PFC Cav1.2 channels (Cav1.2PFCKO mice) by testing male mice in a range of social and nonsocial tests while examining PFC neural activity using in vivo GCaMP6s fiber photometry. We found that during the first investigation of the social and non-social stimulus in the three-chamber test, both Cav1.2PFCKO male mice and Cav1.2PFCGFP controls spent significantly more time with the social stimulus compared to a non-social object. In contrast, during repeat investigations while Cav1.2PFCWT mice continued to spend more time with the social stimulus, Cav1.2PFCKO mice spent equal amount of time with both social and non-social stimuli. Neural activity recordings paralleled social behavior with increase in PFC population activity in Cav1.2PFCWT mice during first and repeat investigations, which was predictive of social preference behavior. In Cav1.2PFCKO mice, there was an increase in PFC activity during first social investigation but not during repeat investigations. These behavioral and neural differences were not observed during a reciprocal social interaction test nor during a forced alternation novelty test. To evaluate a potential deficit in reward-related processes, we tested mice in a three-chamber test wherein the social stimulus was replaced by food. Behavioral testing revealed that both Cav1.2PFCWT and Cav1.2PFCKO mice showed a preference for food over object with significantly greater preference during repeat investigation. Interestingly, there was no increase in PFC activity when Cav1.2PFCWT or Cav1.2PFCKO first investigated the food however activity significantly increased in Cav1.2PFCWT mice during repeat investigations of the food. This was not observed in Cav1.2PFCKO mice. In summary, a reduction in Cav1.2 channels in the PFC suppresses the development of a sustained social preference in mice that is associated with lack of PFC neuronal population activity that may be related to deficits in social reward.

The organization of frontostriatal brain wiring in non-affective early psychosis compared with healthy subjects using a novel diffusion imaging fiber cluster analysis

BACKGROUND

Alterations in brain connectivity may underlie neuropsychiatric conditions such as schizophrenia. We here assessed the degree of convergence of frontostriatal fiber projections in 56 young adult healthy controls (HCs) and 108 matched Early Psychosis-Non-Affective patients (EP-NAs) using our novel fiber cluster analysis of whole brain diffusion magnetic resonance imaging tractography.

METHODS

Using whole brain tractography and our fiber clustering methodology on harmonized diffusion magnetic resonance imaging data from the Human Connectome Project for Early Psychosis we identified 17 white matter fiber clusters that connect frontal cortex (FCtx) and caudate (Cd) per hemisphere in each group. To quantify the degree of convergence and, hence, topographical relationship of these fiber clusters, we measured the inter-cluster mean distances between the endpoints of the fiber clusters at the level of the FCtx and of the Cd, respectively.

RESULTS

We found (1) in both groups, bilaterally, a non-linear relationship, yielding convex curves, between FCtx and Cd distances for FCtx-Cd connecting fiber clusters, driven by a cluster projecting from inferior frontal gyrus; however, in the right hemisphere, the convex curve was more flattened in EP-NAs; (2) that cluster pairs in the right (p = 0.03), but not left (p = 0.13), hemisphere were significantly more convergent in HCs vs EP-NAs; (3) in both groups, bilaterally, similar clusters projected significantly convergently to the Cd; and, (4) a significant group by fiber cluster pair interaction for 2 right hemisphere fiber clusters (numbers 5, 11; p = .00023; p = .00023) originating in selective PFC subregions.

CONCLUSIONS

In both groups, we found the FCtx-Cd wiring pattern deviated from a strictly topographic relationship and that similar clusters projected significantly more convergently to the Cd. Interestingly, we also found a significantly more convergent pattern of connectivity in HCs in the right hemisphere and that 2 clusters from PFC subregions in the right hemisphere significantly differed in their pattern of connectivity between groups.

Effort-Cost Decision-making Among Individuals With Schizophrenia: A Systematic Review and Meta-analysis

Importance

Motivational impairments in schizophrenia are by definition associated with poor outcome. It is postulated that the reduction of goal-directed behavior arises from abnormal trade-offs between rewards and efforts.

Objective

To examine whether schizophrenia is associated with impairments in effort-cost decision-making.

Data Sources

For this systematic review and meta-analysis, the PubMed, ScienceDirect, PsycINFO, Embase, and ClinicalTrials.gov databases were searched from inception to July 2022 for studies that investigated effort-cost decision-making in schizophrenia. Search terms included effort, cost, and schizophrenia.

Study Selection

Consensual criteria for inclusion were peer-reviewed studies published in English that used a computerized effort-cost decision-making behavioral paradigm and compared individuals with schizophrenia with control individuals.

Data Extraction and Synthesis

The Preferred Reporting Items for Systematic Reviews and Meta-analyses reporting guideline was used for abstracting data. Data were extracted independently by 2 authors and then pooled using random-effects sizes and bayesian approaches.

Main Outcomes and Measures

The main outcomes were performance on effort-cost decision-making tasks requiring an effort-reward trade-off, measured by Hedges g effect size. Effects of moderators were tested with meta-regressions and subgroup analyses.

Results

Twenty studies involving 1503 participants were included: 837 individuals with schizophrenia (541 [64.6%] male; mean [SD] age, 35.89 [6.70] years) and 666 control individuals without schizophrenia (360 [54.1%] male; mean [SD] age, 34.16 [5.92] years). Participants with schizophrenia had significantly reduced willingness to expend effort for rewards compared with controls (k = 20; effect size, 0.43; 95% CI, 0.30-0.56; P < .001; I2 = 33.1%; Q test P = .08). The magnitude of the deficit was significantly greater for high-reward trials. The severity of negative symptoms was negatively associated with effort-cost decision-making (k = 8; effect size, -0.33; 95% CI, -0.50 to -0.15; P < .001), while participants with a high number of negative symptoms had a significantly larger impairment in effort-cost decision-making (k = 5; effect size, 0.47; 95% CI, 0.10-0.84; P = .01).

Conclusions and Relevance

In this systematic review and meta-analysis, schizophrenia was associated with deficits in effort allocation as indexed by effort-cost decision-making tasks. Understanding the cognitive and neurobiological mechanisms driving effort allocation impairments may assist in developing novel interventions.

Modulation of ventromedial orbitofrontal cortical glutamatergic activity affects the explore-exploit balance and influences value-based decision-making

The balance between exploration and exploitation is essential for decision-making. The present study investigated the role of ventromedial orbitofrontal cortex (vmOFC) glutamate neurons in mediating value-based decision-making by first using optogenetics to manipulate vmOFC glutamate activity in rats during a probabilistic reversal learning (PRL) task. Rats that received vmOFC activation during informative feedback completed fewer reversals and exhibited reduced reward sensitivity relative to rats. Analysis with a Q-learning computational model revealed that increased vmOFC activity did not affect the learning rate but instead promoted maladaptive exploration. By contrast, vmOFC inhibition increased the number of completed reversals and increased exploitative behavior. In a separate group of animals, calcium activity of vmOFC glutamate neurons was recorded using fiber photometry. Complementing our results above, we found that suppression of vmOFC activity during the latter part of rewarded trials was associated with improved PRL performance, greater win-stay responding and selecting the correct choice on the next trial. These data demonstrate that excessive vmOFC activity during reward feedback disrupted value-based decision-making by increasing the maladaptive exploration of lower-valued options. Our findings support the premise that pharmacological interventions that normalize aberrant vmOFC glutamate activity during reward feedback processing may attenuate deficits in value-based decision-making.

"Goals in Focus"-a targeted CBT approach for motivational negative symptoms of psychosis: study protocol for a randomized-controlled feasibility trial

BACKGROUND

The reduction of goal-directed behavior is the main characteristic in motivational negative symptoms of psychosis as it accounts for the long-term decline in psychological well-being and psychosocial functioning. However, the available treatment options are largely unspecific and show only small effects on motivational negative symptoms. Interventions that directly target the relevant psychological mechanisms are likely to be more effective. For "Goals in Focus", we translated findings from basic clinical research on mechanisms underlying motivational negative symptoms into a tailored and comprehensive novel psychological outpatient treatment program. With this study, we will test the feasibility of the therapy manual and the trial procedures. We also aim to examine first estimates of the effect size that can be expected from "Goals in Focus" to inform the sample size calculation of a subsequent fully powered trial.

METHODS

Thirty participants diagnosed with a schizophrenia spectrum disorder and at least moderate motivational negative symptoms will be randomly assigned to either 24 sessions of "Goals in Focus" over the course of 6 months (n = 15) or to a 6-month wait-list control group (n = 15). Single-blind assessments will be conducted at baseline (t₀) and 6 months after baseline completion (t₁). Feasibility outcomes include patient recruitment, retention, and attendance rates. Acceptability will be rated by trial therapists and by participants at end of treatment. Primary outcome for effect size estimation is the motivational negative symptom subscale sum score of the Brief Negative Symptom Scale at t₁ corrected for baseline values. Secondary outcomes include psychosocial functioning, psychological well-being, depressive symptoms, expressive negative symptoms, negative symptom factor scores, and goal pursuit in everyday life.

DISCUSSION

The feasibility and acceptability data will be used to improve trial procedures and the "Goals in Focus" intervention where necessary. The treatment effect on the primary outcome will provide the basis for the sample size calculation for a fully powered RCT.

TRIAL REGISTRATION

1) ClinicalTrials.gov, NCT05252039 . Registered on 23 February 2022. 2) Deutsches Register Klinischer Studien, DRKS00018083 . Registered on 28 August 2019.

Alpha Event-Related Desynchronization During Reward Processing in Schizophrenia

BACKGROUND

Alterations in the brain's reward system may underlie motivation and pleasure deficits in schizophrenia (SZ). Neuro-oscillatory desynchronization in the alpha band is thought to direct resource allocation away from the internal state, to prioritize processing salient environmental events, including reward feedback. We hypothesized reduced reward-related alpha event-related desynchronization (ERD) in SZ, consistent with less externally focused processing during reward feedback.

METHODS

Electroencephalography was recorded while participants with SZ (n = 54) and healthy control participants (n = 54) played a simple slot machine task. Total alpha band power (8-14 Hz), a measure of neural oscillation magnitude, was extracted via principal component analysis and compared between groups and reward outcomes. The clinical relevance of hypothesized alpha power alterations was examined by testing associations with negative symptoms within the SZ group and with trait rumination, dimensionally, across groups.

RESULTS

A group × reward outcome interaction (p = .018) was explained by healthy control participants showing significant posterior-occipital alpha power suppression to wins versus losses (p < .001), in contrast to participants with SZ (p > .1). Among participants with SZ, this alpha ERD was unrelated to negative symptoms (p > .1). Across all participants, less alpha ERD to reward outcomes covaried with greater trait rumination for both win (p = .005) and loss (p = .002) outcomes, with no group differences in slope.

CONCLUSIONS

These findings demonstrate alpha ERD alterations in SZ during reward outcome processing. Additionally, higher trait rumination was associated with less alpha ERD during reward feedback, suggesting that individual differences in rumination covary with external attention to reward processing, regardless of reward outcome valence or group membership.

The human cerebellum in reward anticipation and reward outcome processing: An activation likelihood estimation meta-analysis

The cerebellum generates internal prediction models and actively compares anticipated and actual outcomes in order to reach a desired end state. In this process, reward can serve as a reinforcer that shapes internal prediction models, enabling context-appropriate behavior. While the involvement of the cerebellum in reward processing has been established in animals, there is no detailed account of which cerebellar regions are involved in reward anticipation and reward outcome processing in humans. To this end, an activation likelihood estimation meta-analysis of functional neuroimaging studies was performed to investigate cerebellar functional activity patterns associated with reward anticipation and reward outcome processing in healthy adults. Results showed that reward anticipation (k=31) was associated with regional activity in the bilateral anterior lobe, bilateral lobule VI, left Crus I and the posterior vermis, while reward outcome (k=16) was associated with regional activity in the declive and left lobule VI. The findings of this meta-analysis show distinct involvement of the cerebellum in reward anticipation and reward outcome processing as part of a predictive coding routine.

Risk for alcohol use problems in severe mental illness: Interactions with sex and racial/ethnic minority status

BACKGROUND

Alcohol use disorder (AUD) is exceedingly common among individuals with bipolar disorder and schizophrenia. However, studies on alcohol use in psychiatric illness rely largely on population surveys with limited representation of severe mental illness (SMI); schizophrenia and bipolar disorder.

METHODS

Using data from the Genomic Psychiatry Cohort (GPC) (Pato MT, 2013), associations of bipolar disorder and schizophrenia with alcohol use problems were examined in a diverse US based sample, considering the influence of self-described race (African Ancestry (AA), European Ancestry (EA), or Latinx Ancestry (LA)), sex, and tobacco use. Participants answered alcohol use problem items derived from the CAGE instrument, yielding a summed "probable" alcohol use disorder (pAUD) risk score.

RESULTS

This study included 1952 individuals with bipolar disorder with psychosis (BDwP), 409 with bipolar disorder without psychosis (BD), 9218 with schizophrenia (SCZ), and 10,416 unaffected individuals. We found that SMI (BDwP, BD, SCZ) was associated with elevated AUD risk scores (B = 0.223, p < 0.001), an association which was strongest in females, particularly those of AA and LA, and in tobacco users. Schizophrenia was associated with the greatest increase in pAUD score (B = 0.141, p < 0.001). pAUD risk scores were increased among participants with bipolar disorder, with greater increases in BDwP (B = 0.125, p < 0.001) than in BD without psychosis (B = 0.027, p < 0.001).

LIMITATIONS

Limitations include reliance on self-report data, screening items for AUD, voluntary recruitment bias, and differences in race/sex distribution between groups, which were statistically adjusted for in analytic models.

CONCLUSIONS

SMI is associated with risk for AUD, particularly among females from racial minority groups, smokers, and those with psychotic disorders.

The Relationship Between Cannabis, Cognition, and Schizophrenia: It's Complicated

The consequences of cannabis use, especially in the context of schizophrenia, have gained increased importance with the legalization of cannabis in North America and across the globe. Cannabis use has multifaceted impacts on cognition in schizophrenia patients and healthy subjects. Healthy subjects, particularly those who initiated cannabis use at earlier ages and used high-potency cannabis for longer durations, exhibited poorer cognition mainly in working memory and attention. Cannabis use in schizophrenia has been associated with symptom exacerbation, longer and more frequent psychotic episodes, and poorer treatment outcomes. However, cannabis-using patients have better overall cognitive performance compared to patients who were not cannabis users. Interestingly, these effects were only apparent in lifetime cannabis users, but not in current (or within last 6 months) users. Moreover, higher frequency and earlier age of cannabis use initiation (i.e., before 17 years of age) were associated with better cognitive performance, although they had an earlier illness onset. Three possible hypotheses seem to come forward to explain this paradox. First, some components of cannabis may have antipsychotic or cognitive-enhancing properties. Secondly, chronic cannabis use may alter endocannabinoid signaling in the brain which could be a protective factor for developing psychosis or cognitive impairments. A third explanation could be their representation of a phenotypically distinct patient group with more intact cognitive functioning and less neurodevelopmental pathology. Multiple factors need to be considered to understand the complex relationship between cannabis, cognitive function, and schizophrenia. In short, age at initiation, duration and rate of cannabis use, abstinence duration, co-use of substances and alcohol, prescribed medications, relative cannabinoid composition and potency of cannabis, presence of genetic and environmental vulnerability factors are prominent contributors to the variability in outcomes. Animal studies support the disruptive effects of Δ9-tetrahydrocannabinol (THC) administration during adolescence on attention and memory performance. They provide insights about interaction of cannabinoid receptors with other neurotransmitter systems, such as GABA and glutamate, and other regulatory molecules, such as PSD95 and synaptophysin. Cannabidiol (CBD), on the other hand, can improve cognitive deficits seen in neurodevelopmental and chemically-induced animal models of schizophrenia. Future studies focusing on bridging the translational gaps between human and animal studies, through the use of translationally relevant methods of exposure (e.g., vaping), consistent behavioral assessments, and congruent circuit interrogations (e.g., imaging) will help to further clarify this complex picture.

Maternal immune activation as an epidemiological risk factor for neurodevelopmental disorders: Considerations of timing, severity, individual differences, and sex in human and rodent studies

Epidemiological evidence suggests that one's risk of being diagnosed with a neurodevelopmental disorder (NDD)-such as autism, ADHD, or schizophrenia-increases significantly if their mother had a viral or bacterial infection during the first or second trimester of pregnancy. Despite this well-known data, little is known about how developing neural systems are perturbed by events such as early-life immune activation. One theory is that the maternal immune response disrupts neural processes important for typical fetal and postnatal development, which can subsequently result in specific and overlapping behavioral phenotypes in offspring, characteristic of NDDs. As such, rodent models of maternal immune activation (MIA) have been useful in elucidating neural mechanisms that may become dysregulated by MIA. This review will start with an up-to-date and in-depth, critical summary of epidemiological data in humans, examining the association between different types of MIA and NDD outcomes in offspring. Thereafter, we will summarize common rodent models of MIA and discuss their relevance to the human epidemiological data. Finally, we will highlight other factors that may interact with or impact MIA and its associated risk for NDDs, and emphasize the importance for researchers to consider these when designing future human and rodent studies. These points to consider include: the sex of the offspring, the developmental timing of the immune challenge, and other factors that may contribute to individual variability in neural and behavioral responses to MIA, such as genetics, parental age, the gut microbiome, prenatal stress, and placental buffering.

Action selection in early stages of psychosis: an active inference approach

BACKGROUND

To interact successfully with their environment, humans need to build a model to make sense of noisy and ambiguous inputs. An inaccurate model, as suggested to be the case for people with psychosis, disturbs optimal action selection. Recent computational models, such as active inference, have emphasized the importance of action selection, treating it as a key part of the inferential process. Based on an active inference framework, we sought to evaluate previous knowledge and belief precision in an action-based task, given that alterations in these parameters have been linked to the development of psychotic symptoms. We further sought to determine whether task performance and modelling parameters would be suitable for classification of patients and controls.

METHODS

Twenty-three individuals with an at-risk mental state, 26 patients with first-episode psychosis and 31 controls completed a probabilistic task in which action choice (go/no-go) was dissociated from outcome valence (gain or loss). We evaluated group differences in performance and active inference model parameters and performed receiver operating characteristic (ROC) analyses to assess group classification.

RESULTS

We found reduced overall performance in patients with psychosis. Active inference modelling revealed that patients showed increased forgetting, reduced confidence in policy selection and less optimal general choice behaviour, with poorer action-state associations. Importantly, ROC analysis showed fair-to-good classification performance for all groups, when combining modelling parameters and performance measures.

LIMITATIONS

The sample size is moderate.

CONCLUSION

Active inference modelling of this task provides further explanation for dysfunctional mechanisms underlying decision-making in psychosis and may be relevant for future research on the development of biomarkers for early identification of psychosis.