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Task-free brain activity exhibits spontaneous fluctuations between functional states, characterized by synchronized activation patterns in distributed resting-state (RS) brain networks. The temporal dynamics of the networks' electrophysiological signatures reflect individual variations in brain activity and connectivity linked to mental states and cognitive functions and can predict or monitor vulnerability to develop psychiatric or neurological disorders. In particular, RS alpha fluctuations modulate perceptual sensitivity, attentional shifts, and cognitive control, and could therefore reflect a neural correlate of increased vulnerability to sensory distortions, including the proneness to hallucinatory experiences. We recorded 5 min of RS EEG from 33 non-clinical individuals varying in hallucination proneness (HP) to investigate links between task-free alpha dynamics and vulnerability to hallucinations. To this end, we used a dynamic brain state allocation method to identify five recurrent alpha states together with their spatiotemporal dynamics and most active brain areas through source reconstruction. The dynamical features of a state marked by activation in somatosensory, auditory, and posterior default-mode network areas predicted auditory and auditory-verbal HP, but not general HP, such that individuals with higher vulnerability to auditory hallucinations spent more time in this state. The temporal dynamics of spontaneous alpha activity might reflect individual differences in attention to internally generated sensory events and altered auditory perceptual sensitivity. Altered RS alpha dynamics could therefore instantiate a neural marker of increased vulnerability to auditory hallucinations. [ABSTRACT FROM AUTHOR]

Voices are a complex and rich acoustic signal processed in an extensive cortical brain network. Specialized regions within this network support voice perception and production and may be differentially affected in pathological voice processing. For example, the experience of hallucinating voices has been linked to hyperactivity in temporal and extra-temporal voice areas, possibly extending into regions associated with vocalization. Predominant self-monitoring hypotheses ascribe a primary role of voice production regions to auditory verbal hallucinations (AVH). Alternative postulations view a generalized perceptual salience bias as causal to AVH. These theories are not mutually exclusive as both ascribe the emergence and phenomenology of AVH to unbalanced top-down and bottom-up signal processing. The focus of the current study was to investigate the neurocognitive mechanisms underlying predisposition brain states for emergent hallucinations, detached from the effects of inner speech. Using the temporal voice area (TVA) localizer task, we explored putative hypersalient responses to passively presented sounds in relation to hallucination proneness (HP). Furthermore, to avoid confounds commonly found in in clinical samples, we employed the Launay-Slade Hallucination Scale (LSHS) for the quantification of HP levels in healthy people across an experiential continuum spanning the general population. We report increased activation in the right posterior superior temporal gyrus (pSTG) during the perception of voice features that positively correlates with increased HP scores. In line with prior results, we propose that this rightlateralized pSTG activation might indicate early hypersensitivity to acoustic features coding speaker identity that extends beyond own voice production to perception in healthy participants prone to experience AVH. [ABSTRACT FROM AUTHOR]

Voices are a complex and rich acoustic signal processed in an extensive cortical brain network. Specialized regions within this network support voice perception and production and may be differentially affected in pathological voice processing. For example, the experience of hallucinating voices has been linked to hyperactivity in temporal and extra-temporal voice areas, possibly extending into regions associated with vocalization. Predominant self-monitoring hypotheses ascribe a primary role of voice production regions to auditory verbal hallucinations (AVH). Alternative postulations view a generalized perceptual salience bias as causal to AVH. These theories are not mutually exclusive as both ascribe the emergence and phenomenology of AVH to unbalanced top-down and bottom-up signal processing. The focus of the current study was to investigate the neurocognitive mechanisms underlying predisposition brain states for emergent hallucinations, detached from the effects of inner speech. Using the temporal voice area (TVA) localizer task, we explored putative hypersalient responses to passively presented sounds in relation to hallucination proneness (HP). Furthermore, to avoid confounds commonly found in in clinical samples, we employed the Launay-Slade Hallucination Scale (LSHS) for the quantification of HP levels in healthy people across an experiential continuum spanning the general population. We report increased activation in the right posterior superior temporal gyrus (pSTG) during the perception of voice features that positively correlates with increased HP scores. In line with prior results, we propose that this right-lateralized pSTG activation might indicate early hypersensitivity to acoustic features coding speaker identity that extends beyond own voice production to perception in healthy participants prone to experience AVH.

Auditory verbal hallucinations (AVH) are reported in approximately 70% of psychotic patients, but they also may occur in approximately 10% of the healthy general population. AVH have been related to altered processing of vocal emotions at both sensory and higher-order processing stages in psychotic patients. However, it remains to be clarified whether individuals with high hallucination proneness (HP) exhibit a similar pattern of alterations. We investigated the impact of HP on vocal emotional perception and specified whether manipulations of acoustic cues, such as sound intensity and duration, related to salience changes, affect the time course of voice processing reflected in event-related potentials (ERP) of the electroencephalogram. Participants varying in HP performed a task involving the categorization of emotional nonverbal vocalizations (neutral, anger, and amusement) differing in duration and intensity. ERP results demonstrated interactive effects of HP, valence, and acoustic cues on both early (N1, P2) and late (Late Positive Potential [LPP]) processing stages. Higher HP was associated with decreased N1 and increased P2 amplitudes in response to louder and longer neutral (vs. positive) vocalizations, as well as with a larger LPP to louder and longer negative (vs. neutral) vocalizations. These findings suggest that HP is associated with changes in the processing of vocal emotions that might be related to altered salience of acoustic representations of emotions. Consistent with prior studies with psychotic patients, these findings show that altered perception of vocal emotions may additionally contribute to the experience of hallucinations in nonclinical samples. [ABSTRACT FROM AUTHOR]

As a risk factor of hallucination proneness, the level of mindfulness has not yet been investigated in non-clinical participants. Other potential mediators, such as mental distress (depression, anxiety, and stress) which contribute to hallucination proneness also need to be assessed. This study investigated the mediating effect of mental distress in predicting hallucination proneness based on mindfulness. A number of 168 Iranian university students completed three questionnaires: (1) the five-facet mindfulness questionnaire, (2) the depression, anxiety and stress scale; and (3) the revised hallucination scale. The results showed that there was a significant association between levels of mindfulness and hallucination proneness. Mental distress has a significant effect on four facets of mindfulness questionnaire and an insignificant effect on one facet (awareness) in predicting hallucination. These effects were both direct and indirect. The indirect effect was developed by the mediating role of mental distress. [ABSTRACT FROM AUTHOR]

Interacting with imaginary companions (ICs) is now considered a natural part of childhood for many children, and has been associated with a range of positive developmental outcomes. Recent research has explored how the phenomenon of ICs in childhood and adulthood relates to the more unusual experience of hearing voices (or auditory verbal hallucinations, AVH). Specifically, parallels have been drawn between the varied phenomenology of the two kinds of experience, including the issues of quasi-perceptual vividness and autonomy/control. One line of research has explored how ICs might arise through the internalization of linguistically mediated social exchanges to form dialogic inner speech. We present data from two studies on the relation between ICs in childhood and adulthood and the experience of inner speech. In the first, a large community sample of adults (N = 1,472) completed online the new Varieties of Inner Speech – Revised (VISQ-R) questionnaire (Alderson-Day et al., 2018) on the phenomenology of inner speech, in addition to providing data on ICs and AVH. The results showed differences in inner speech phenomenology in individuals with a history of ICs, with higher scores on the Dialogic, Evaluative, and Other Voices subscales of the VISQ-R. In the second study, a smaller community sample of adults (N = 48) completed an auditory signal detection task as well as providing data on ICs and AVH. In addition to scoring higher on AVH proneness, individuals with a history of ICs showed reduced sensitivity to detecting speech in white noise as well as a bias toward detecting it. The latter finding mirrored a pattern previously found in both clinical and nonclinical individuals with AVH. These findings are consistent with the view that ICs represent a hallucination-like experience in childhood and adulthood which shows meaningful developmental relations with the experience of inner speech.

Interacting with imaginary companions (ICs) is now considered a natural part of childhood for many children, and has been associated with a range of positive developmental outcomes. Recent research has explored how the phenomenon of ICs in childhood and adulthood relates to the more unusual experience of hearing voices (or auditory verbal hallucinations, AVH). Specifically, parallels have been drawn between the varied phenomenology of the two kinds of experience, including the issues of quasi-perceptual vividness and autonomy/control. One line of research has explored how ICs might arise through the internalization of linguistically mediated social exchanges to form dialogic inner speech. We present data from two studies on the relation between ICs in childhood and adulthood and the experience of inner speech. In the first, a large community sample of adults (N = 1,472) completed online the new Varieties of Inner Speech – Revised (VISQ-R) questionnaire (Alderson-Day et al., 2018) on the phenomenology of inner speech, in addition to providing data on ICs and AVH. The results showed differences in inner speech phenomenology in individuals with a history of ICs, with higher scores on the Dialogic, Evaluative, and Other Voices subscales of the VISQ-R. In the second study, a smaller community sample of adults (N = 48) completed an auditory signal detection task as well as providing data on ICs and AVH. In addition to scoring higher on AVH proneness, individuals with a history of ICs showed reduced sensitivity to detecting speech in white noise as well as a bias toward detecting it. The latter finding mirrored a pattern previously found in both clinical and nonclinical individuals with AVH. These findings are consistent with the view that ICs represent a hallucination-like experience in childhood and adulthood which shows meaningful developmental relations with the experience of inner speech. [ABSTRACT FROM AUTHOR]

Hallucination-like experiences (HLEs) are typically defined as sensory perceptions in the absence of external stimuli. Multidimensional tools, able to assess different facets of HLEs, are helpful for a better characterization of hallucination proneness and to investigate the cross-national variation in the frequencies of HLEs. The current study set out to establish the validity, factor structure, and measurement invariance of the Launay-Slade Hallucinations Scale-Extended (LSHS-E), a tool to assess HLEs. A total of 4419 respondents from 10 countries were enrolled. Network analyses between the LSHS-E and the 3 dimensions of the Community Assessment of Psychic Experiences (CAPE) were performed to assess convergent and divergent validity of the LSHS-E. Confirmatory factor analysis was used to test its measurement invariance. The best fit was a 4-factor model, which proved invariant by country and clinical status, indicating cross-national stability of the hallucination-proneness construct. Among the different components of hallucination-proneness, auditory-visual HLEs had the strongest association with the positive dimension of the CAPE, compared with the depression and negative dimensions. Participants who reported a diagnosis of a mental disorder scored higher on the 4 LSHS-E factors. Small effect size differences by country were found in the scores of the 4 LSHS-E factors even after taking into account the role of socio-demographic and clinical variables. Due to its good psychometric properties, the LSHS-E is a strong candidate tool for large investigations of HLEs. [ABSTRACT FROM AUTHOR]

Introduction:The purpose of this study was to examine the relationship of sleep quality to proneness to hallucinations and the mediating role of dissociation and unusual sleep experiences in a nonclinical sample. Methods:One hundred and seventy-seven participants completed a questionnaire on sleep quality, a dissociative experiences scale, an unusual sleep experiences scale and a hallucination proneness scale. Results:The results showed a significant positive association between quality of sleep and hallucination proneness, dissociation and unusual sleep experiences, and that dissociation and unusual sleep experiences fully mediated between sleep quality and hallucination proneness. Conclusions:Our study highlights the importance of variables related to sleep quality and unusual sleep experiences and dissociation in understanding hallucinations, and the importance of taking these variables into consideration in designing intervention directed at reducing distress caused by hallucinations. [ABSTRACT FROM PUBLISHER]

Introduction:Auditory hallucinations are associated with signal detection biases. We examine the extent to which suggestions influence performance on a signal detection task (SDT) in highly hallucination-prone and low hallucination-prone students. We also explore the relationship between trait suggestibility, dissociation and hallucination proneness. Method:In two experiments, students completed on-line measures of hallucination proneness (the revised Launay–Slade Hallucination Scale; LSHS-R), trait suggestibility (Inventory of Suggestibility) and dissociation (Dissociative Experiences Scale-II). Students in the upper and lower tertiles of the LSHS-R performed an auditory SDT. Prior to the task, suggestions were made pertaining to the number of expected targets (Experiment 1,N = 60: high vs. low suggestions; Experiment 2,N = 62, no suggestion vs. high suggestion vs. no voice suggestion). Results:Correlational and regression analyses indicated that trait suggestibility and dissociation predicted hallucination proneness. Highly hallucination-prone students showed a higher SDT bias in both studies. In Experiment 1, both bias scores were significantly affected by suggestions to the same degree. In Experiment 2, highly hallucination-prone students were more reactive to the high suggestion condition than the controls. Conclusion:Suggestions may affect source-monitoring judgments, and this effect may be greater in those who have a predisposition towards hallucinatory experiences. [ABSTRACT FROM PUBLISHER]

More than a third of the population report childhood adversity, and these experiences are associated with an increased risk of clinical and subclinical psychosis. The reason why some people go on to develop mental health problems and others do not is a key question for study. It has been hypothesized that dissociative processes mediate the relationship between early adversity and psychosis. The current study assessed whether dissociation, and specifically depersonalization (one component of dissociation), plays a mediating role in the relationship between childhood maltreatment and both hallucination proneness and delusional ideation. The study used a cross-sectional design and recruited a student sample to assess these relationships in a nonclinical group. Dissociation mediated the relationship between early maltreatment and both hallucination proneness and delusional ideation. In terms of specific dissociative processes, depersonalization did not mediate hallucination proneness or delusional ideation. Absorption mediated hallucination proneness; dissociative amnesia (negatively) and absorption mediated delusional ideation. It is likely that dissociation interferes with the encoding of traumatic information in nonclinical as well as clinical groups and in certain ways. Absorption may be particularly relevant. For some people, traumatic memories may intrude into conscious awareness in adulthood as psychotic-type experience. [ABSTRACT FROM AUTHOR]

BACKGROUND: The occurrence of psychotic-like experiences and schizotypal features in the general nonclinical population may imply a connection with psychosis-related liability. OBJECTIVE: This study was designed to examine the role of resilience in the relationship of hallucination and delusion–like experiences and schizotypal features to psychological distress in a nonclinical sample. DESIGN: The study sample (n = 432 university students) was selected through a stratified cluster sampling procedure, and measures of hallucination proneness, delusion proneness, schizotypal personality, and psychological distress were administered. RESULTS: While all three indices of psychotic-like experiences correlated with one another, only hallucination proneness and schizotypal personality features correlated with psychological distress and only schizotypal traits correlated with resilience. Schizotypy was found to have an indirect effect on distress through resilience. CONCLUSIONS: Findings imply the possibility of two types of schizotypy, with high or low resilience. It appears that schizotypes with low resilience may be susceptible to adversity and mental disorders, while high resilience may be protective. [ABSTRACT FROM AUTHOR]

We investigated whether dysfunctional metacognitive beliefs (negative beliefs about uncontrollability and danger of thoughts) mediate the relationship between temperamental characteristics of behavior and hallucinatory-like experiences in healthy subjects ( n =137). Our analyses showed that four temperamental traits (emotional reactivity, perseveration, endurance and briskness) were mediated by negative beliefs about uncontrollability and danger of thoughts in relation to hallucination proneness. Our research tentatively suggests that temperament affects hallucination proneness via metacognition. [ABSTRACT FROM AUTHOR]

Individuals differ in their ability to attribute actions to self or other. This variance is thought to explain, in part, the experience of voice-hearing. Misattribution can also be context-driven. For example, causal ambiguity can arise when the actions of two or more individuals are coordinated and produce similar effects (e.g., music-making). Experience in such challenging contexts may refine skills of action attribution. Forty participants completed a novel finger-tapping task which parametrically manipulated the proportion of control that ‘self’ versus ‘other’ possessed over resulting auditory tones. Results showed that action misattribution peaked in the middle of the self-to-other continuum and was biased towards other. This pattern was related to both high hallucination-proneness and to low musical-experience. Findings suggest not only that causal ambiguity plays a key role in agency but also that action attribution abilities may improve with practice, potentially providing an avenue for remediation of the positive symptoms of schizophrenia. [ABSTRACT FROM AUTHOR]

The purpose of this work was to study the relationship between self-focused attention and mindfulness in participants prone to hallucinations and others who were not. A sample of 318 healthy participants, students at the universities of Sevilla and Almería, was given the Launay-Slade Hallucinations Scale-revised (LSHS-R, Bentall & Slade, 1985). Based on this sample, two groups were formed: participants with high (n = 55) and low proneness (n = 28) to hallucinations. Participants with a score higher than a standard deviation from the mean in the LSHS-R were included in the high proneness group, participants with a score lower than a standard deviation from the mean in the LSHR-R were included in the second one. All participants were also given the Self-Absorption Scale (SAS, McKenzie & Hoyle, 2008) and the Southampton Mindfulness Questionnaire (SMQ, Chadwick et al., 2008). The results showed that participants with high hallucination proneness had significantly higher levels of public (t(80) = 6.81, p < .001) and private (t(77) = 7.39, p < .001) self-focused attention and lower levels of mindfulness (t(81) = -4.56, p < .001) than participants in the group with low hallucination proneness. A correlational analysis showed a negative association between self-focused attention (private and public) and mindfulness (r = -0.23, p < .001; r = -0.38, p < .001 respectively). Finally, mindfulness was found to partly mediate between self-focused attention and hallucination proneness. The importance of self-focused attention and mindfulness in understanding the etiology of hallucinations discussed and suggest some approaches to their treatment. [ABSTRACT FROM AUTHOR]

‘Jumping to conclusions’ (JTC) is a reasoning bias consisting of a tendency to take a decision without having enough information about an event. It has been related to the presence of delusions. The aim of the present study was to assess the relationship between three tasks differing in complexity and concept which assess JTC and cognitive functioning in a sample of people with schizophrenia and healthy participants. We also assessed which cognitive variables, after controlling for psychotic symptoms, explained the presence of JTC in each sample. A total of 43 patients with schizophrenia and 57 healthy participants were assessed with a cognition battery including executive function, verbal memory, and IQ. JTC was assessed with three tasks (probability of 85:15; 60:40, and 60:40 with emotional component). Patients were also assessed on psychotic and affective symptoms and the healthy participants on proneness to hallucinations and delusion. The present study demonstrates a clear relationship between JTC and cognitive functioning, especially in working memory, verbal memory, and cognitive processing speed in people with schizophrenia and in healthy participants. However no relationship was found in the emotional task of JTC. Hallucinations (in people with schizophrenia) and proneness to hallucinations (in the healthy participants) are related to JTC. Our results suggest that diverse psychological interventions such as cognitive remediation, cognitive behavioral therapy and meta-cognitive training might contribute to reducing JTC bias. [ABSTRACT FROM AUTHOR]

IntroductionThe purpose of this work was to study the relationship of absorption, depersonalisation, and self-focused attention in subjects prone to hallucination. MethodsA sample of 218 healthy subjects was given the LSHS-R Hallucination Scale (Bentall & Slade, 1985). Three groups, subjects with high, medium, and low hallucination proneness, were formed from this sample. The Tellegen Absorption Scale (TAS; Tellegen & Atkinson, 1974), Cambridge Depersonalisation Scale (CDS; Sierra & Berrios, 2000), and Self-Absorption Scale (SAS; McKenzie & Hoyle, 2008) were also given to all the participants. The Metacognitions Questionnaire (MCQ-30; Wells & Cartwright-Hatton, 2004) was used as a covariant to control for the effects of emotional vulnerability on the dependent variables studied. ResultsThe results showed that subjects highly prone to hallucinations had significantly higher absorption, depersonalisation, and self-focused attention than the subjects in the other two groups. A hierarchical regression analysis showed that absorption and depersonalisation predict hallucination proneness. ConclusionsThe importance of the absorption, depersonalisation, and self-focused attention variables for understanding the aetiology of hallucinations is discussed in the Conclusions, where some approaches to its treatment are also suggested. [ABSTRACT FROM PUBLISHER]

Abstract: It has been suggested that certain types of auditory hallucinations may be the by-product of a perceptual system that has evolved to be oversensitive to threat-related stimuli. People with schizophrenia and high schizotypes experience visual as well as auditory hallucinations, and have deficits in processing facial emotions. We sought to determine the relationship between visual hallucination proneness and the tendency to misattribute threat and non-threat related emotions to neutral faces. Participants completed a questionnaire assessing visual hallucination proneness (the Revised Visual Hallucination Scale – RVHS). High scoring individuals (N =64) were compared to low scoring individuals (N =72) on a novel emotion detection task. The high RVHS group made more false positive errors (ascribing emotions to neutral faces) than the low RVHS group, particularly when detecting threat-related emotions. All participants made more false positives when neutral faces were presented to the right visual field than to the left visual field. Our results support continuum models of visual hallucinatory experience in which tolerance for false positives is highest for potentially threatening emotional stimuli and suggest that lateral asymmetries in face processing extend to the misperception of facial emotion. [Copyright &y& Elsevier]

Abstract: Disordered or maladaptive meta-cognitive processing appears to be a prominent feature for some individuals with a diagnosis of schizophrenia. We sought to establish whether healthy individuals distinguished either in terms hallucination proneness (HP) or level of schizotypy could also be differentiated on the sub-scales of the Meta-cognitions Questionnaire (MCQ), or a modified version of it in which items about worry were replaced with items specifically related to thinking. A total of 106 healthy volunteers completed the Oxford and Liverpool Inventory of Feelings and Experiences and Launay–Slade hallucination scale, the Schizotypal Personality Questionnaire and two versions of the MCQ: the original which assesses five domains of meta-cognition and an adapted version in which items relating to worry had been replaced by items relating to thinking or reflecting on thinking (MCQ-th). ANOVA indicated highly significant differences between three groups of individuals differentiated in terms of high, medium and low proneness to hallucinations on four of the five MCQ sub-scales, and three of the four MCQ-th factors. Regression analyses indicated that the MCQ factors encompassing (1) a sense of uncontrollability of thinking (and the perceived attendant dangers of this) and (2) negative beliefs about thinking related to suspicion and punishment were the strongest predictors of high schizotypy. Individuals who score higher on a measure of HP are more likely to display patterns of meta-cognitive processing that resemble, in certain respects, those reported in individuals with a diagnosis of schizophrenia. High schizotypy predicts a negative appraisal about both the controllability and consequences of thinking. [Copyright &y& Elsevier]

Abstract: We investigated a mediating role of meta-cognitions in the relationship between Cloninger's temperament and character dimensions and hallucination proneness among healthy subjects (n=135). Two character dimensions—self-directedness and self-transcendence—were related to hallucination proneness. Negative beliefs about uncontrollability of thoughts partially mediated the relationship between these two character dimensions and hallucination proneness. [Copyright &y& Elsevier]