Psychotic like experiences as part of a continuum of psychosis: Associations with effort-based decision-making and reward responsivity

Differential relationship between meditation methods and psychotic-like and mystical experiences

Much work has investigated beneficial effects of mindfulness-based meditation methods, but less work has investigated potential risks and differences across meditation methods. We addressed this in a large pre-registered online survey including 613 mediators where we correlated participants' experience with fifty meditation techniques to psychotic-like experiences (PLEs) and mystical experiences. We found a positive correlation for both PLEs and mystical experiences with techniques aiming at reducing phenomenological content ('null-directed', NDM) or classified as non-dual or less embodied. In contrast, methods aiming at achieving an enhanced cognitive state (CDM), also described as 'attentional' or strongly embodied, showed negative correlations with PLEs. Interestingly, participants' subjectively perceived that all types of meditation techniques were preventative of PLEs but less so for NDM. Participants differed in their reasons for meditating, broadly grouped into associated with spiritual exploration and associated with health. Participants who meditated for spiritual reasons were more likely to choose NDM techniques and more likely to experience PLEs. In contrast, participants who meditated for health-related reasons were more likely to choose CDM techniques. This study provides important information for meditators about the relationship of different techniques with PLEs and the moderating influences of individual traits.

Endorsement of psychotic-like experiences and problematic cannabis use associated with worse executive functioning performance in undergraduates

BACKGROUND

Emerging adults who endorse more positive psychotic-like experiences (PLEs; bizarre experiences, delusional ideations) may experience greater cannabis-related impairments in executive function. Negative and depressive PLEs are also associated with cannabis use, however, less is known about their relation to executive functioning. Here, we hypothesize that high positive PLEs and cannabis use are associated with worse performance on computerized versions of the Iowa Gambling Task (IGT) and the Card Sorting Task (CST); exploratory analyses are conducted with negative and depressive PLEs.

METHODS

We recruited university students (N = 543) who completed an online study consisting of self-report measures of problematic cannabis use (Cannabis Use Disorder Identification Test; CUDIT-R) and PLEs (Community Assessment of Psychotic Experiences; CAPE). Of these, n=270 completed the CST and n=251 completed the IGT.

RESULTS

Problematic cannabis use and high endorsement of positive PLEs related to significantly worse performance on the IGT and greater perseverative errors on the CST. In addition, people who endorsed high levels of positive PLEs were also significantly more likely to complete the IGT with less money relative to those who endorsed fewer PLEs, regardless of cannabis use. Further analyses based on negative PLEs revealed a similar pattern for perseverative errors on the CST; depressive PLEs were not related to task performance.

CONCLUSION

Findings highlight that problematic cannabis use and more frequent and distressing positive PLEs are associated with poorer executive functioning. Thus, executive functioning may have implications for intervention among those high on both attributes, who are at high risk of onset of psychosis.

[Willingness to expend effort for rewards in individuals at clinical high-risk for psychosis: a relationship with the severity and stability of negative symptoms]

OBJECTIVE

To identify the deficit in willingness to expend effort and its association with negative symptoms in the high-risk for psychosis (CHR) group.

MATERIAL AND METHODS

The study included young men: 45 patients, who met CHR criteria and were treated for a depressive episode, and 15 controls. All subjects completed a modified version of the Effort Expenditure for Rewards Task (EEfRT). The CHR group was assessed with the SOPS, SANS and HDRS at the beginning and at the end of treatment. EEfRT was performed only at the end of treatment.

RESULTS

The CHR group was significantly less likely to choose high effort tasks across reward probability and magnitude levels compared with the control group (all p<0.001). No significant correlations were found between the rate of selecting the high effort task and the negative syndrome domains of amotivation and diminished expression. The subgroups of CHR with stable and transient (i.e., with a reduction >50% during treatment) negative symptoms, which were identified by a cluster analysis, did not differ in the willingness to expend effort.

CONCLUSION

The study confirmed a decrease in the willingness to expend effort in the CHR group; however, this deficit was only weakly correlated with negative symptoms and persisted after the symptoms reduction during treatment, which requires future studies to investigate mechanisms underlying impaired effort expenditure for rewards in CHR.

Childhood maltreatment mediates the effect of the genetic background on psychosis risk in young adults

Childhood maltreatment (CM) and genetic vulnerability are both risk factors for psychosis, but the relations between them are not fully understood. Guided by the recent identification of genetic risk to CM, this study investigates the hypothesis that genetic risk to schizophrenia also increases the risk of CM and thus impacts psychosis risk. The relationship between schizophrenia polygenetic risk, CM, and psychotic-like experiences (PLE) was investigated in participants from the Utrecht Cannabis Cohort (N = 1262) and replicated in the independent IMAGEN cohort (N = 1740). Schizophrenia polygenic risk score (SZ-PRS) were calculated from the most recent GWAS. The relationship between CM, PRS, and PLE was first investigated using multivariate linear regression. Next, mediation of CM in the pathway linking SZ-PRS and PLE was examined by structural equation modeling, while adjusting for a set of potential mediators including cannabis use, smoking, and neuroticism. In agreement with previous studies, PLE were strongly associated with SZ-PRS (B = 0.190, p = 0.009) and CM (B = 0.575, p < 0.001). Novel was that CM was also significantly associated with SZ-PRS (B = 0.171, p = 0.001), and substantially mediated the effects of SZ-PRS on PLE (proportion mediated = 29.9%, p = 0.001). In the replication cohort, the analyses yielded similar results, confirming equally strong mediation by CM (proportion mediated = 34.7%, p = 0.009). Our results suggest that CM acts as a mediator in the causal pathway linking SZ-PRS and psychosis risk. These findings open new perspectives on the relations between genetic and environmental risks and warrant further studies into potential interventions to reduce psychosis risk in vulnerable people.

Adaptive and maladaptive features of schizotypy clusters in a community sample

Schizotypal personality traits correlate with psychopathology and impaired functional outcome. Yet advantageous aspects of positive schizotypy may exist which could promote resilience and creativity, and several studies have identified a high positive but low negative schizotypy group with some signs of adaptation. The aim of our study was to clarify whether such individuals demonstrate only traits associated with well-being, or they also have traits that predict impairment. Participants (N = 643 students, 71.5% female) completed measures of schizotypy, resilience, self-esteem, self-concept clarity, and absorption. We identified four clusters: an overall low schizotypy, an overall high schizotypy, a disorganised-interpersonal schizotypy and a positive schizotypy cluster. The overall high schizotypy cluster seemed to be the most vulnerable as it was the least resilient and showed widespread maladaptation, whereas the high positive schizotypy cluster had intact self-esteem and high resilience and its elevated absorption may hold the promise for adaptive outcomes such as creativity and positive spirituality. However, the high positive schizotypy cluster lacked self-concept clarity. The results suggest that individuals showing high positive and low negative schizotypy demonstrate features promoting mental well-being to an extent that is higher than in all the other clusters, while their self-concept impairment is similar to that observed in the high and the disorganised-interpersonal schizotypy clusters. Better understanding of these factors could be informative for prevention and treatment of psychosis-spectrum disorders.

Reprint of: Internalising symptoms mediate the longitudinal association between childhood inflammation and psychotic-like experiences in adulthood

Psychotic-like experiences (PLEs) are part of a continuum of psychosis. Previous longitudinal studies highlighted a relationship between peripheral inflammation during childhood and onset of PLEs in adulthood. In this study, we tested if this association is mediated by internalising and externalising symptoms experienced during childhood and adolescence. To test this hypothesis, we used data from the Avon Longitudinal Study of Parents and Children (ALSPAC). We investigated a subsample of 4525 individuals from this cohort with data on interleukin 6 (IL-6) and C-reactive protein (CRP) in childhood (age 9 years). We measured PLEs at age 18 years, and we used latent growth curve modelling to estimate longitudinal trajectories of internalising and externalising symptoms from ages 9 to 16 years. The individual predicted values of the intercept (set at baseline, 9 years) and the slope (rate of annual change) were then used in the mediation analysis. There was evidence for full mediation by the intercept of internalising symptoms. Our findings suggest that inflammation during childhood may be relevant for the future onset of PLEs via its association with a high level of internalising symptoms. These findings, although obtained from a non-clinical population, provide an additional step in advancing knowledge on the relationship between inflammation and symptoms of the psychosis continuum.

What you want may not be what you like: A test of the aberrant salience hypothesis in schizophrenia risk

Motivational abnormalities represent a key area of dysfunction in individuals with, or at risk for, schizophrenia and severely limit broad domains of functioning in these populations. The aberrant salience hypothesis posits that motivational abnormalities are the result of an over-attribution of salience to nonpleasurable stimuli but an under-attribution of salience to pleasurable ones. Consequently, people "want" what they do not "like" but do not "want" what they "like." However, it is unclear how this hypothesis manifests in schizophrenia risk beyond monetary rewards. The current research provided a multimodal investigation of the aberrant salience hypothesis in people with elevated psychotic-like experiences (PLEs) who are at risk for developing psychosis. Study 1 examined the link between liking and incentive salience using a neurobiological indicator of incentive salience (contingent negative variation/CNV) in 23 PLEs and 21 Control participants. The PLEs group showed diminished CNV reactivity to pleasant (vs. neutral) social images, which was driven by an augmented response to neutral stimuli. Study 2 examined liking, incentive salience, and conscious wanting experience using a psychological indicator of incentive salience (positive spontaneous thoughts/PSTs) in 38 PLEs and 246 Control participants. The PLEs group showed diminished correspondence between liking, PSTs, and conscious wanting across diverse reward contexts. Collectively, individuals with PLEs over-attribute salience to neutral stimuli and, to a lesser degree, under-attribute salience to rewards. Findings of the current research support abnormal salience attribution as a trait-like feature implicated in the pathophysiology and development of schizophrenia and provide valuable insights on research and treatment of this illness.

Internalising symptoms mediate the longitudinal association between childhood inflammation and psychotic-like experiences in adulthood

Psychotic-like experiences (PLEs) are part of a continuum of psychosis. Previous longitudinal studies highlighted a relationship between peripheral inflammation during childhood and onset of PLEs in adulthood. In this study, we tested if this association is mediated by internalising and externalising symptoms experienced during childhood and adolescence. To test this hypothesis, we used data from the Avon Longitudinal Study of Parents and Children (ALSPAC). We investigated a subsample of 4525 individuals from this cohort with data on interleukin 6 (IL-6) and C-reactive protein (CRP) in childhood (age 9 years). We measured PLEs at age 18 years, and we used latent growth curve modelling to estimate longitudinal trajectories of internalising and externalising symptoms from ages 9 to 16 years. The individual predicted values of the intercept (set at baseline, 9 years) and the slope (rate of annual change) were then used in the mediation analysis. There was evidence for full mediation by the intercept of internalising symptoms. Our findings suggest that inflammation during childhood may be relevant for the future onset of PLEs via its association with a high level of internalising symptoms. These findings, although obtained from a non-clinical population, provide an additional step in advancing knowledge on the relationship between inflammation and symptoms of the psychosis continuum.

Striatum-related functional activation during reward- versus punishment-based learning in psychosis risk

Psychosis is strongly related to increased striatal dopamine. However, the neural consequences of increased striatal dopamine in psychosis risk are still not fully understood. Consistent with an increase in striatal dopamine, in previous research, psychosis risk has been associated with neural EEG evidence of a greater response to unexpected reward than unexpected punishment feedback on a reversal-learning task. However, previous research has not directly examined whether psychosis risk is associated with altered striatal activation when receiving unexpected feedback on this task. There were two groups of participants: an antipsychotic medication-naive psychosis risk group (n = 21) who had both (a) extreme levels of self-reported psychotic-like beliefs and experiences and (b) interview-rated current-attenuated psychotic symptoms; and a comparison group (n = 20) who had average levels of self-reported psychotic-like beliefs and experiences. Participants completed a reversal-leaning task during fMRI scanning. As expected, in both ROI and whole-brain analyses, the psychosis risk group exhibited greater striatal activation (for whole-brain analyses, the peak was located in the right caudate) to unexpected reward than unexpected punishment feedback relative to the comparison group. These results indicate that psychosis risk is associated with a relatively increased neural sensitivity to unexpected reward than unexpected punishment outcomes and appears consistent with increased striatal dopamine. The results may help us better understand and detect striatal dysfunction in psychosis risk.