Targeting the link between loneliness and paranoia via an interventionist-causal model framework

Does social isolation predict the emergence of psychotic-like experiences? Results from the experience sampling method study

BACKGROUND

Several studies have shown that social isolation and loneliness are associated with the occurrence of psychotic experiences. However, dynamics of these phenomena in people with subclinical experiences, commonly referred to as psychotic-like experiences (PLEs), remains largely unknown. Therefore, in this study we performed a temporal network analysis to model dynamic predictions between social isolation, loneliness, negative affect, social stress, and PLEs.

METHODS

A total of 77 drug-naïve individuals with PLEs from a transdiagnostic sample were enrolled. Data were obtained using the experience sampling method (ESM). The ESM questionnaires were delivered during 7 consecutive days (6 assessments per day). Therefore, 3234 data entries were analyzed.

RESULTS

Social isolation predicted next-moment emergence of PLEs through the effects on loneliness and negative affect. Also, PLEs appeared to predict next-moment loneliness, but not social isolation, through the effects on negative affect. Social stress did not predict any variables in the network. However, it was predicted by previous-moment PLEs and social isolation. Negative affect had the highest in-strength and out-strength centrality.

CONCLUSIONS

Findings from the present study indicate that social isolation might predict the emergence of PLEs through the effects of momentary loneliness and negative affect. Also, loneliness might be bidirectionally associated with PLEs. Interventions targeting negative affect and social isolation might be beneficial in people with PLEs.

Social identification and paranoia

Paranoia is associated with variation in social behaviour, such as lower inclination to trust others or to behave generously in economic game settings. Such variation may stem, in part, from a reduced tendency to socially identify with others, although previous studies have reported mixed results. We tested whether paranoia involves altered social identification in a pre-registered online study investigating the relationship between a measure of social identification, paranoia, and social behaviours in economic games. We successfully manipulated social identification, but paranoia was associated with slightly increased social identification overall. Neither paranoia nor social identification predicted behaviour in the economic games, and there was no interaction between paranoia and social identification regarding trusting and cooperative behaviours. Our results converge with recent work suggesting that more paranoid individuals may harbour a higher tendency to perceive themselves as having similar beliefs to others. We discuss some key areas for future research to progress understanding in this area.

[Recent developments in the modeling and psychological management of persecutory ideation]

Persecutory ideas are a major clinical problem and are associated with impaired functioning, reduced compliance with medication and increased risk of hospitalization. Persecutory ideation is defined as the false conviction that others are threatening or conspiring against one. Although persecutory delusions are mainly described and experienced in schizophrenia spectrum disorders, they also occur in other neurological and psychiatric diagnoses including Alzheimer disease, epilepsy, depression, mania, dementia and post-traumatic stress disorder. Moreover, epidemiological data from general and clinical populations indicated that paranoid beliefs occur on a hierarchy of severity and are present to a lesser degree in the general population, with paranoid delusions representing the severe end of a continuum. In this review we focus on the important advances following a decade of research from psychological sciences, and more particularly the work of Daniel Freeman and Philippa Garety in England. Their work has demonstrated that a range of causal factors are involved in the development and maintenance of delusions beyond the traditional cognitive and behavioural models. Indeed, there is now well-validated evidence that sleep disturbances, worry proneness, reasoning biases, such as failure to consider alternative explanations or belief confirmation bias, abnormal experiences such as hallucinations, negative self-beliefs, and safety behaviours, are central factors that contribute to the paranoid phenomenon. In this review, we describe each of these causal factors in detail as well as the clinical interventions developed by Freeman and his collaborators, including the integrative and modular "Feeling Safe" intervention. Broadly speaking, the aim of this psychological intervention is for patients to relearn safety by exposing them to situations they consider as potentially dangerous after reduction of the influence of the maintenance factors described above. A recent publication showed that the Feeling Safe program led to recovery in persecutory delusions for 50% of patients having poor response to antipsychotic medication, making the intervention as the most effective psychological treatment for persecutory delusions. Finally, we will critically discuss the efficacy data from the numerous clinical studies validating its effectiveness. Prospects for the implementation of the Feeling Safe program in France also is discussed.

Experimental studies of paranoid thinking in clinical and nonclinical populations: a systematic review and meta-analysis

Paranoia is common in clinical and nonclinical populations, consistent with continuum models of psychosis. A number of experimental studies have been conducted that attempt to induce, manipulate or measure paranoid thinking in both clinical and nonclinical populations, which is important to understand causal mechanisms and advance psychological interventions. Our aim was to conduct a systematic review and meta-analysis of experimental studies (non-sleep, non-drug paradigms) on psychometrically assessed paranoia in clinical and nonclinical populations. The review was conducted using PRISMA guidelines. Six databases (PsycINFO, PubMed, EMBASE, Web of Science, Medline and AMED) were searched for peer-reviewed experimental studies using within and between-subject designs to investigate paranoia in clinical and nonclinical populations. Effect sizes for each study were calculated using Hedge's g and were integrated using a random effect meta-analysis model. Thirty studies were included in the review (total n = 3898), which used 13 experimental paradigms to induce paranoia; 10 studies set out to explicitly induce paranoia, and 20 studies induced a range of other states. Effect sizes for individual studies ranged from 0.03 to 1.55. Meta-analysis found a significant summary effect of 0.51 [95% confidence interval 0.37-0.66, p < 0.001], indicating a medium effect of experimental paradigms on paranoia. Paranoia can be induced and investigated using a wide range of experimental paradigms, which can inform decision-making about which paradigms to use in future studies, and is consistent with cognitive, continuum and evolutionary models of paranoia.

Do loneliness and social exclusion breed paranoia? An experience sampling investigation across the psychosis continuum

Background

The role of loneliness and social exclusion in the development of paranoia is largely unexplored. Negative affect may mediate potential associations between these factors. We investigated the temporal relationships of daily-life loneliness, felt social exclusion, negative affect, and paranoia across the psychosis continuum.

Method

Seventy-five participants, including 29 individuals with a diagnosis of non-affective psychosis, 20 first-degree relatives, and 26 controls used an Experience Sampling Method (ESM) app to capture the fluctuations in loneliness, feelings of social exclusion, paranoia, and negative affect across a 1-week period. Data were analysed with multilevel regression analyses.

Results

In all groups, loneliness and feelings of social exclusion were independent predictors of paranoia over time (b = 0.05, p < .001 and b = 0.04, p < .05, respectively). Negative affect predicted paranoia (b = 0.17, p < .001) and partially mediated the associations between loneliness, social exclusion, and paranoia. It also predicted loneliness (b = 0.15, p < .0001), but not social exclusion (b = 0.04, p = .21) over time. Paranoia predicted social exclusion over time, with more pronounced effects in controls (b = 0.43) than patients (b = 0.19; relatives: b = 0.17); but not loneliness (b = 0.08, p = .16).

Conclusion

Paranoia and negative affect worsen in all groups following feelings of loneliness and social exclusion. This highlights the importance of a sense of belonging and being included for mental well-being. Loneliness, feeling socially excluded, and negative affect were independent predictors of paranoid thinking, suggesting they represent useful targets in its treatment.

Polygenic contribution to the relationship of loneliness and social isolation with schizophrenia

Previous research suggests an association of loneliness and social isolation (LNL-ISO) with schizophrenia. Here, we demonstrate a LNL-ISO polygenic score contribution to schizophrenia risk in an independent case-control sample (N = 3,488). We then subset schizophrenia predisposing variation based on its effect on LNL-ISO. We find that genetic variation with concordant effects in both phenotypes shows significant SNP-based heritability enrichment, higher polygenic contribution in females, and positive covariance with mental disorders such as depression, anxiety, attention-deficit hyperactivity disorder, alcohol dependence, and autism. Conversely, genetic variation with discordant effects only contributes to schizophrenia risk in males and is negatively correlated with those disorders. Mendelian randomization analyses demonstrate a plausible bi-directional causal relationship between LNL-ISO and schizophrenia, with a greater effect of LNL-ISO liability on schizophrenia than vice versa. These results illustrate the genetic footprint of LNL-ISO on schizophrenia.

Loneliness in Personality Disorders

PURPOSE OF REVIEW

Loneliness is a common experience in patients with personality disorders (PDs) that are characterized by impairment in self (identity, self-direction) and interpersonal functioning (empathy, intimacy). Here, we review studies assessing the association of loneliness with PD or PD traits including DSM-5's Alternative Model of PD (AMPD).

RECENT FINDINGS

The number of loneliness studies varied greatly among different PDs with most studies conducted in borderline PD. Across PDs, loneliness was associated with the severity of psychopathological symptoms and with several AMPD trait domains. Consequently, loneliness may contribute to PD severity and further impair personality functioning. Loneliness and PD share intra- and interpersonal factors (i.e., increased rejection sensitivity, information processing biases, social withdrawal) and common origins in childhood maltreatment that may explain their close association. Future research needs to investigate mechanisms on how loneliness and core characteristics of PD mutually reinforce each other in order to therapeutically address loneliness in PD.

Loneliness and the psychosis continuum: a meta-analysis on positive psychotic experiences and a meta-analysis on negative psychotic experiences

There is an increase in interest in the relationships between loneliness and psychosis. The notion of psychosis continuum implies that psychotic experiences extend from clinical populations with psychotic disorders to non-clinical populations. This meta-analytic review aimed to examine the respective associations of loneliness with positive and negative psychotic experiences along the psychosis continuum. A systematic database search was conducted and a total of 30 studies were included in the first meta-analysis and 15 studies were included in the second meta-analysis. There was a medium association between loneliness and positive psychotic experiences (r = 0.302, p < 0.001). In particular, the association between loneliness and paranoia was robust (r = 0.448, p < 0.001). The second meta-analysis revealed a medium association between loneliness and negative psychotic experiences (r = 0.347, p < 0.001). The associations between loneliness and both positive and negative psychotic experiences were found to be smaller among clinical than non-clinical samples. The above findings provided evidence for the associations between loneliness and the two core dimensions of psychotic experiences along the phenomenological continuum. Future research should examine the dynamics of these relationships in both clinical and non-clinical samples, preferably using a single-symptom approach.