Cardiff Anomalous Perceptions Scale Research Articles

Can you believe your eyes? Positive schizotypy is associated with increased susceptibility to the Müller-Lyer illusion

Background and hypothesisVisual illusions provide a unique opportunity to understand cognitive and perceptual alterations in schizophrenia-spectrum conditions. Schizophrenia patients often exhibit increased susceptibility to the Müller-Lyer illusion. Here, we investigate susceptibility to the Müller-Lyer visual illusion in the general population with different levels of schizotypy. Study designWe assessed a population-based convenience sample (N = 263) on an online platform. In addition to basic demographics, participants completed the Müller-Lyer illusion, the Cardiff Anomalous Perceptions Scale (CAPS) to measure perceptual anomalies, and the Multidimensional Schizotypy Scale – Brief (MSS-B) for schizotypic traits. To evaluate what predicts susceptibility to the illusion, we fitted a large set of multilevel logistic regression models and performed model averaging over the coefficients. Study resultsWe found support for increased illusion susceptibility among individuals with high positive schizotypy. However, we did not find a comparable effect for anomalous perceptions alone, or for negative or disorganized schizotypy. ConclusionsThe increased Müller-Lyer effect in positive schizotypy might be specific to delusion-like beliefs and magical ideation. Further research is needed to clarify how a hierarchical Bayesian formulation of brain function (e.g. imbalances between bottom-up perceptual processing and substantial reliance on prior expectations) can account for the Müller-Lyer effect in schizophrenia-spectrum conditions.

The dimensionality of perceptual anomalies and their relationships with bullying victimization among Chinese adolescents: From a network perspective

Anomalous perceptual experiences in adolescents are common and may predict future psychotic disorders and other psychopathologies. However, the underlying structure and their specific relationships with bullying victimizations, a typical stressor for adolescents, remain unclear. Therefore, the current study aimed to clarify the structure of perceptual anomalies as assessed by the Cardiff Anomalous Perceptions Scale (CAPS) using exploratory graph analysis (EGA), a new factor retention method based on network psychometrics. The second aim was to explore whether specific dimensions of perceptual anomalies are particularly associated with certain forms of bullying victimization. Data from a validated sample of 1199 Chinese adolescents (56.0 % females, age range: 14–20) on perceptual anomalies and bullying victimizations were analyzed using network approaches, including EGA and mixed graphical modeling (mgm). Results showed that each anomalous perception was experienced by 13.8–50.3 % of the participants. EGA identified four dimensions: aberrant bodily perceptions, altered daily experiences, chemosensation (i.e., abnormal gustatory and olfactory experiences), and clinical psychosis (i.e., visual and auditory hallucinatory experiences). Among them, the altered daily experiences dimension possessed the highest centrality. Physical bullying and cyberbullying were directly and positively linked to two of the aberrant bodily experiences. Bootstrap analyses suggest that the results are reliable. The current findings support the existence of multiple contributive factors to perceptual anomalies and underscore the importance of bullying prevention in reducing mental health risks for adolescents, particularly the risk of psychosis.

The association between childhood bullying victimisation and childhood maltreatment with the clinical expression of bipolar disorder

Adverse childhood experiences are significantly associated with a worse clinical expression of bipolar disorder, however, the literature has mainly focused on childhood maltreatment (abuse and neglect) with little attention paid to other forms of adversity, such as childhood bullying victimisation (referred to here as bullying), although this is known to have a negative impact on different psychiatric illnesses. The current study aimed to investigate the association between bullying victimisation and the clinical expression of bipolar disorder individually and in combination with childhood maltreatment. This investigation consisted of 63 individuals with a diagnosis of bipolar disorder (mean age 61.4 years) who completed the Retrospective Bullying Questionnaire and the Childhood Trauma Questionnaire to measure exposure to bullying and childhood maltreatment, respectively. The clinical expression variables were assessed using self-report instruments, these were: the Cardiff Anomalous Perceptions Scale (psychotic symptoms), Suicide Behaviours Questionnaire, Self-Report Manic Inventory, Beck Anxiety and Depression Inventories. The results showed that exposure to bullying was significantly associated with more suicidal behaviours (F(1,61) = 11.02, p < .01, η2 = 0.15) and psychotic symptoms (F(1,61) = 4.21, p < .05, η2 = .06). When bullying and childhood maltreatment histories were combined, the results showed that individuals with a history of both adversity types reported significantly more suicidal behaviours (F(2,60) = 6.59, p < .01, R2=.18) compared to those with a history of one or neither form of adversity. The sample size, age and gender distribution, limit the generalisability of the findings. However, the current results underscore the need to account for bullying victimisation when considering the adverse childhood experiences-bipolar disorder relationship, especially its clinical expression.

Persecutory ideation and anomalous perceptual experiences in the context of the COVID-19 outbreak in France: what's left one month later?

PurposeBeyond the effects of the coronavirus pandemic on the public's health, the length of lockdown and its possible psychological impacts on populations is heavily debated. However, the consequences of lockdown on psychotic symptoms have been poorly investigated. MethodsAn online survey was run from April 13 to May 11, 2020; a total of 728 French subjects from the general population were included in the study. We assessed the perceived impact of the COVID-19 outbreak, length of isolation, diagnosis/symptoms/hospitalisation related to the COVID-19 (oneself and family). Paranoid ideations and hallucination-like experiences were assessed via the Paranoia Scale and the Cardiff Anomalous Perceptions Scale, respectively. Self-reported measures of negative affect, loneliness, sleep difficulties, jumping to conclusion bias, repetitive thoughts, among others, were also included. ResultsFinal regression model for paranoia indicated that socio-demographic variables (age, sex and education), loneliness, cognitive bias, anxiety, experiential avoidance, repetitive thoughts and hallucinations were associated with paranoia (R2 = 0.43). For hallucinations, clinical variables as well as the quality of sleep, behavioural activation, repetitive thoughts, anxiety and paranoia were associated with hallucinations in our sample (R2 = 0.27). Neither length of isolation nor the perceived impact of the COVID-19 pandemic were associated with psychotic experiences in the final models. ConclusionsNo evidence was found for the impact of isolation on psychotic symptoms in the general population in France one month after the lockdown. It nevertheless confirms the preeminent role of several factors previously described in the maintenance and development of psychotic symptoms in the context of a pandemic and lockdown measures.

Factor structure and age invariance of the Cardiff Anomalous Perceptions Scale (CAPS) in healthy older and younger adults.

Although anomalous perceptual experiences are common in healthy older adults, they remain poorly characterized. In particular, it is unclear whether the phenomenology of these experiences differs between healthy older and younger adults. The current study examined similarities and differences in the factor structure of the Cardiff Anomalous Perceptions Scale (CAPS) in healthy, community-dwelling older (n = 194; Mage = 71.89, SD = 7.74, range = 52-91; 69.1% female) and younger adults (n = 421, Mage = 19.40, SD = 2.44, range = 17-34; 69.6% female; N = 615), using exploratory and confirmatory factor analysis, together with measurement invariance testing. The results found that a 2-factor correlated model comprising 23 of the original 32 CAPS items provided the best fit to the data. Further, scalar invariance was found between the two samples, indicating equivalence of the factor structure, factor loadings, and thresholds by age group. Compared with younger adults, the latent group means of older adults were also found to be equal on Factor 1, but significantly lower on Factor 2. Evidence of scalar age invariance on the CAPS suggests that this tool is valid for making comparisons between older and younger adults on two dimensions of anomalous perceptual experiences. Further, the results suggest that anomalous perceptions in the general community may be characterized by two components: anomalous body-centered self-experiences (e.g., alterations in body, touch, smell, and taste perception) and anomalous external experiences (e.g., auditory, visual, and sensed presence hallucinations); each of which may have different causes, correlates, and consequences for healthy ageing. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Exploration of anomalous perceptual experiences in migraine between attacks using the Cardiff Anomalous Perceptions Scale.

Distortions in sensory experiences that precede a migraine attack have been extensively documented, the most well-known being the visual aura. Distortions in the experience of other senses are also reported as part of an aura, albeit less frequently, together with changes in the perception or ownership of the body or body parts. There are many examples of differences in aspects of visual perception between migraine and control groups, between attacks, but not as much on unusual experiences involving other senses, the sense of the body or the experience of the environment. Seventy-seven migraine (33 with aura) and 74 control participants took part. Anomalous perceptions were experienced by both migraine and control groups, but more with migraine experienced them and rated them as more distressing, intrusive and frequent. Associations with reports of visual triggers of migraine and visual discomfort are presented. This study is the first to show relationships between these factors.

Supplemental Material for Factor Structure and Age Invariance of the Cardiff Anomalous Perceptions Scale (CAPS) in Healthy Older and Younger Adults

Supplemental Material for Factor Structure and Age Invariance of the Cardiff Anomalous Perceptions Scale (CAPS) in Healthy Older and Younger Adults

Validation of the Spanish-language Cardiff Anomalous Perception Scale.

The Cardiff Anomalous Perceptions Scale (CAPS) is a psychometric measure of hallucinatory experience. It has been widely used in English and used in initial studies in Spanish but a full validation study has not yet been published. We report a validation study of the Spanish-language CAPS, conducted in both Spain and Colombia to cover both European and Latin American Spanish. The Spanish-language version of the CAPS was produced through back translation with slight modifications made for local dialects. In Spain, 329 non-clinical participants completed the CAPS along with 40 patients with psychosis. In Colombia, 190 non-clinical participants completed the CAPS along with 21 patients with psychosis. Participants completed other psychometric scales measuring psychosis-like experience to additionally test convergent and divergent validity. The Spanish-language CAPS was found to have good internal reliability. Test-retest reliability was slightly below the cut-off, although could only be tested in the Spanish non-clinical sample. The scale showed solid construct validity and a principal components analysis broadly replicated previously reported three component factor structures for the CAPS.

El constructo de “límite” y experiencias anómalas en psíquicos

This study aims at distinguishing self-named psychics (or clairvoyant) from a control group (non-psychics) considering the variable “ frequency of unusual perceptual experiences” (anomalous perception), and the psychological construct “limit”. Participants were divided into psychics and non-psychics (people who had psychic experiences but no extrasensory capacities). Both psychics (N = 87) and the control group (N = 112) completed the Cardiff Anomalous Perceptions Scale (CAPS), the Revised Transliminality Scale (RTS), the Limits Questionnaire, and a scale to measure their psychic abilities. All the hypotheses were confirmed: psychics had higher scores on transliminality, anomalous perception and “fine limit” in comparison with non-psychics. In addition, the variable “anomalous experiences” was the best predictor for the psychics group (β = .073; p = .03), followed by the variable “fine limit”. Psychics would be those who were able to pass the “continuity hypothesis” of Hartmann’s limit due to their familiarity with their own capacity to alter their conscience.

Multidimensionalidad del Habla Interna y su relación con las percepciones anómalas

BackgroundInner speech is a common human experience. Recently, there have been studies linking this experience with cognitive functions, such as problem solving, reading, writing, autobiographical memory, and some disorders, such as anxiety and depression. In addition, inner speech is recognised as the main source of auditory hallucinations. ObjectivesThe main purpose of this study is to establish the factor structure of Varieties of Inner Speech Questionnaire (VISQ) in a sample of the Colombian population. Furthermore, it aims at establishing a link between VISQ and abnormal perceptions. MethodThis was a cross-sectional study in which 232 college students were assessed using the VISQ and the Cardiff Anomalous Perceptions Scale (CAPS). ResultsThrough an exploratory factor analysis, a structure of three factors was found: Other Voices in the Internal Speech, Condensed Inner speech, and Dialogical/Evaluative Inner speech, all of them with acceptable levels of reliability. Gender differences were found in the second and third factor, with higher averages for women. Positive correlations were found among the three VISQ and the two CAPS factors: Multimodal Perceptual Alterations and Experiences Associated with the Temporal Lobe. ConclusionsThe results are consistent with previous findings linking the factors of inner speech with the propensity to auditory hallucination, a phenomenon widely associated with temporal lobe abnormalities. The hallucinations associated with other perceptual systems, however, are still weakly explained.

The relationship between different types of dissociation and psychosis-like experiences in a non-clinical sample.

This study investigated whether detachment-type dissociation, compartmentalisation-type dissociation or absorption was most strongly associated with psychosis-like experiences in the general population. Healthy participants (N=215) were tested with the Dissociative Experiences Scale (DES, for detachment-related dissociative experiences); the Harvard Group Scale of Hypnotic Susceptibility (HGSHS: A, for dissociative compartmentalisation); the Tellegen Absorption Scale (TAS, for non-clinical 'functional' dissociative experience); and two measures of psychotic-like experiences, the 21-item Peters et al. Delusions Inventory (PDI-21) and the Cardiff Anomalous Perceptions Scale (CAPS). In multiple regression analyses, DES and TAS but not HGSHS: A scores were found to be significantly associated with PDI-21 and CAPS overall scores. A post hoc hierarchical cluster analysis checking for cluster overlap between DES and CAPS items, and the TAS and CAPS items showed no overlap between items on the DES and CAPS and minimal overlap between TAS and CAPS items, suggesting the scales measure statistically distinct phenomena. These results show that detachment-type dissociation and absorption, but not compartmentalisation-type dissociation are significantly associated with psychosis-like experiences in a non-clinical population.

Estructura factorial de la Cardiff Anomalous Perceptions Scale (CAPS) en una muestra de población colombiana

BackgroundThe continuum hypothesis of psychosis assumes that hallucinations are not exclusive of psychotic disorders. A number of psychometric tests have been developed to assess psychosis using a dimensional model. ObjectivesTo determine the factorial structure of the Cardiff Anomalous Perceptions Scale (CAPS) for the Colombian population, and to contrast the fit of two factor models previously reported in the literature by conducting a confirmatory factor analysis (CFA). MethodsThis was a cross-sectional study in which 207 subjects from the general population were assessed using the Cardiff Anomalous Perceptions Scale. ResultsA two-factor structure with acceptable ordinal alpha coefficients (α=.88 and α=.87) was found. One factor gathered items related to multimodal perceptual alterations, and a second factor grouped items related with experiences linked to the temporal lobe. The analysis of the first factor indicated that it was dependent on cultural issues for the interpretation of sensations. The second factor appeared almost unchanged on diverse populations, suggesting its transcultural character. When comparing the models proposed by Bell et al. and Jaen-Moreno et al. using the data obtained from the sample, the confirmatory factor analysis conducted indicated inadequate goodness-of-fit indexes (χ2). However, some incremental goodness-of-fit indexes (normalized χ2 [RMSEA]) were acceptable. The Jaén-Moreno et al. model showed the best fit to the data collected from the Colombian sample. ConclusionsThe factorial structure of CAPS for the Colombian population appears to be sensitive to cultural issues, especially when describing anomalous sensorial experiences.

Hallucinations and inhibitory functioning in healthy young adults with high and low levels of hypomanic personality traits

Introduction. Hallucinations in schizophrenia and hallucination proneness in healthy young adults are associated with a common cognitive mechanism, namely impaired inhibitory control. Hallucinatory-like experiences also seem related to hypomanic symptoms in non-clinical participants; however, the mechanisms involved are unknown. We sought to examine self-reported hallucinatory/anomalous perceptual experiences in students selected for high versus low levels of hypomanic personality traits, and whether hypomania is characterised by deficient inhibitory control.Method. Undergraduate students with either high (n = 26) or low (n = 28) scores on the Hypomanic Personality Scale-Revised (HPS-20) were compared on: (1) the Launay Slade Hallucination Scale-Revised (LSHS-R), a measure of hallucination proneness, (2) the Cardiff Anomalous Perceptions Scale (CAPS) and (3) the Inhibition of Currently Irrelevant Memories (ICIM) task, an index of intentional inhibition.Results. The high HPS group had higher total scores, as well as higher frequency (on CAPS only), intrusiveness and distress (CAPS) scores compared to the low HPS group. They also produced significantly more false alarms on the second run of the ICIM task than the low hypomania traits group.Conclusions. Frequent, intrusive and distressing perceptual anomalies and proneness to hallucinations tend to occur in healthy individuals with hypomanic personality traits and may be associated with transient difficulties with inhibitory control. Inhibitory control may be a cognitive marker of vulnerability to hallucinations across diagnostic boundaries.

Relationships of perceived public stigma of mental illness and psychosis-like experiences in a non-clinical population sample.

Studies on the association between psychopathology, perceived public stigma, and labeling in mental illness have focused primarily on severe but rare mental disorders, especially schizophrenia, or other clinically defined psychotic disorders. Although evidence is mounting that psychosis-like experiences show high prevalence in the general population and lead to an increased risk of psychotic disorders, little is known about how psychosis-like experiences independently affect perceived public stigma in the non-clinical population. The aim of the present study was to examine the relationship between psychosis-like experiences and perceived public stigma in a non-clinical sample. For this cross-sectional study, we recruited 524 individuals (239 male, 285 female) who had no lifetime history of psychiatric disorder. Participants completed questionnaires that asked for sociodemographic and clinical information, a measure of perceived public stigma (Perceived Psychiatric Stigma Scale [PPSS]), and two measures of psychosis-like experiences (Peters et al. Delusions Inventory [PDI]; Cardiff Anomalous Perceptions Scale [CAPS]). Of the sociodemographic characteristics analyzed in this study-gender, age, education level, marital status, and religion-only age simultaneously influenced PPSS, PDI, and CAPS scores. As hypothesized, perceived public stigma was positively correlated with measures of psychosis-like experiences, even after controlling for age. Furthermore, the perceived stigma was more strongly associated with delusion proneness than with anomalous perceptual experiences. The association between psychopathology and perceived public stigma appears to extend beyond clinically defined psychosis to more common psychosis-like experiences in a sample drawn from the general Han Chinese population.

EPA-1392 – Transcranial direct-current stimulation (tDCS) in patients with schizophrenia

Introduction Some 25%–30% of patients with schizophrenia have auditory verbal hallucinations that are refractory to antipsychotic drugs. transcranial directcurrent stimulation (tDCS) is a novel somatic treatment proposed for hallucinations and negative symptoms (Brunelin et al. 2012). Objectives/Aims We aimed to assess the efficacy of tDCS in reducing the severity of auditory verbal hallucinations as well as negative symptoms in patients with schizophrenia. Methods Six patients (aged 41–66 year) with schizophrenia and medication-refractory auditory verbal hallucinations were enrolled. Positive and Negative Syndrome Scale (PANSS) and Cardiff Anomalous Perceptions Scale (CAPS) were administered as outcome measure, before (T0) and after tDCS (T1), to assess treatment response. tDCS delivered by a HDCstim (Newronika, Milano, Italy) (2mA, twenty minutes, twice a day for 5 consecutive days) with the anodal electrode over the left dorsolateral prefrontal cortex and cathodal electrode on the left temporo parietal cortex. Results The patients tolerated well the procedure and there was no side effect. After tDCS auditory verbal hallucinations improved by 33% in frequency (T0 vs T1 p=0.03) and by 40% in distress (T0 vs T1 p=0.02), for up to one month. Negative symptoms as measured by the PANSS also decreased by 24% (T0 vs T1, p=0.02). Conclusion The results of this small, open tDCS trial prompt the further studies with controlled, double blind design in a larger sample size of schizophrenic patients. Nonetheless, our findings are in line with available data reporting a beneficial effects of tDCS in schizophrenia (Brunelin et al. 2012).

Autistic traits and abnormal sensory experiences in adults.

Sensory processing abnormalities are common in autism spectrum disorders (ASD), and now form part of the Diagnostic and Statistical Manual 5th Edition (DSM-5) diagnostic criteria, but it is unclear whether they characterize the ‘broader phenotype’ of the disorder. We recruited adults (n = 772) with and without an ASD and administered the Autism Quotient (AQ) along with the Adult/Adolescent Sensory Profile (AASP), the Cardiff Anomalous Perceptions Scale (CAPS), and the Glasgow Sensory Questionnaire (GSQ), all questionnaire measures of abnormal sensory responsivity. Autism traits were significantly correlated with scores on all three sensory scales (AQ/GSQ r = 0.478; AQ/AASP r = 0.344; AQ/CAPS r = 0.333; all p < 0.001). This relationship was linear across the whole range of AQ scores and was true both in those with, and without, an ASD diagnosis. It survived correction for anxiety trait scores, and other potential confounds such as mental illness and migraine.

1847 – Cognitive and emotional anomalies implicated in pathogenesis of delusional idea in delusional disorder

Introduction Four theoretical models have been postulated in formation and maintenance of delusional idea in schizophrenia: 1. Cognitive biases (attentional bias, jumping-to-conclusion, need-for-clousure, attributional bias), 2. Social cognition alterations (theory-of-mind, emotion facial recognition), 3. Perceptive alterations of anomalous experiences and 4. Emotional anomalies (anxiety, depression, self-esteem, “self” discrepancies). However, there is poor evidence about the implication of these anomalies in pathogenesis of delusional idea in delusional disorder (DD). Objectives To exam the joint influence of these anomalies in delusional activity in DD. Methods We studied the delusional activity measured by the “Maudsley Assessment of Delusion Schedule” in 68 patients with DD (n=68) diagnosed by SCID-I (DSM-IV-TR). Cognitive biases were evaluated by “Emotional Stroop”, “Experimental Beads Task”, “Need-for-Closure Scale”, “Internal, Personal and Situational Attributions Questionnaire”. Social cognition alterations were measured by Faux-pas Task and Eyes-Test; perceptive alterations by “Cardiff Anomalous Perceptions Scale”; and emotional anomalies by “Hamilton Anxiety Rating Scale”, “Beck Depression Inventory”, “Rosenberg Self-esteem Scale” and “Personal Qualities Questionnaire”. The relationship between delusional activity and these cognitive anomalies were examined using lineal regression models controlled by socio-demographic characteristics, premorbid IQ (“NART”), negative symptomatology (“PANSS”) and neuropsychological function (attention, verbal learning, working memory and executive function). Results High scores in delusion activity were significantly associated with high scores in jumping-to-conclusion and depression and low scores in faux-pas and self-esteem, after being adjusted by number of studied years and negative symptomatology. Conclusions Cognitive biases (jumping-to-conclusions), social cognition deficit (faux-pas) and emotional alterations are the most implicated anomalies in formation and maintenance of delusional idea in DD.

Assessing Anomalous Perceptual Experiences in Nonpsychiatric Individuals and Outpatients with Psychosis in Taiwan: An Investigation Using the Cardiff Anomalous Perceptions Scale (CAPS)

The Cardiff anomalous perceptions scale (CAPS) has been recently designed for the assessment of anomalous perceptual experiences in the general population, and includes dimensions that measure distress, intrusiveness, and frequency. The purpose of this study was to assess the psychometric properties of a Taiwanese version of the CAPS. The English version of the CAPS was translated into Taiwanese (CAPS-T) and the latter was applied to this study. We administered the questionnaire to a consecutive sample of 192 participants with (n=106; clinical group including schizophrenia and affective psychosis) or without psychotic disorders (n=86; non-clinical group). In addition to the CAPS-T, the Taiwanese version of the brief psychiatric symptom rating scale (BSRS) measured the severity of the psychopathology. We also tested the psychometric properties of the CAPS-T including construct validity, internal consistency, test-retest reliability, and convergent and discriminative validity. Overall, the CAPS-T showed good construct validity, internal consistency, and stability over time and correlated significantly with the psychoticism subscale of the BSRS. As predicted, the mean differences in CAPS-T scores between participants with or without a psychotic disorder were significant. Convergent and discriminative validity were satisfactory. A score of 5 was found to the best threshold in discriminating between clinical and non-clinical samples. Our findings indicate that the Taiwanese version of the CAPS is a reliable and valid instrument to measure the multidimensionality of perceptual anomalies in general and appears to complement the clinical measures of psychosis proneness in Taiwan.

P-804 - Neurofunctional basis of social cognition in subclinical paranoid ideation and social anxiety

Impaired social functioning is a hallmark characteristic of several mental disorders including those characterized by paranoid ideation (P) and social anxiety (SA). Social deficits have been related to impaired social cognition. To investigate the neurofunctional basis of social cognition in people with subclinical P and SA. 13 healthy participants with high paranoid ideation; 12 healthy participants with high social anxiety. Procedures and Instruments: Paranoid Thoughts Scale, Liebowitz Social Anxiety Scale, Cardiff Anomalous Perceptions Scale. Brain response to social stimuli was investigated with two event-related fMRI experiments with implicit processing of facial. expressions of happiness and anger in two different intensities, and with faces expressing no emotion. People with P recruit differentially and positively the Left Lingual (p < 0,05 FWEcorr), and close to significant (p < 0,06 FWEcorr) the Right Caudate when processing neutral faces. People with SA only showed significant positive differences (p < 0,05 FWEcorr) in the Right Inferior frontal gyrus when processing anger stimuli at 100%. When comparing both groups, we did not find significant differences. The preliminary results indicate a stronger recruitment of emotional and visual areas in P subjects when processing neutral faces and a stronger recruitment of cognitive processing areas in SA subjects when processing angry faces.

The psychometric properties of the Taiwanese version of the Cardiff Anomalous Perceptions Scale

Background The Cardiff Anomalous Perceptions Scale (CAPS) has been recently designed for the assessment of anomalous perceptual experiences in the general population and includes dimensions that measure distress, intrusiveness, and frequency. The purpose of this study was to assess the psychometric properties of a Taiwanese version of the CAPS. Methods The English version of the CAPS was translated into Taiwanese (CAPS-T), and the latter was applied to this study. We administered the questionnaire to a consecutive sample of 192 participants with (n = 106; clinical group including schizophrenia and affective psychosis) or without (n = 86; nonclinical group) psychotic disorders. In addition to the CAPS-T, the Taiwanese version of the Brief Psychiatric Symptom Rating Scale measured the severity of the psychopathology. We also tested the psychometric properties of the CAPS-T including construct validity, internal consistency, test-retest reliability, and convergent and discriminative validity. Results Overall, the CAPS-T showed good construct validity, internal consistency, and stability over time and correlated significantly with the psychoticism subscale of the Brief Psychiatric Symptom Rating Scale. As predicted, the mean differences in CAPS-T scores between participants with or without a psychotic disorder were significant. Convergent and discriminative validity were satisfactory. A score of 5 was found to be the best threshold in discriminating between clinical and nonclinical samples. Conclusions Our findings indicate that the Taiwanese version of the CAPS is a reliable and valid instrument to measure the multidimensionality of perceptual anomalies in general and appears to complement the clinical measures of psychosis proneness in Taiwan.