The neurophenomenology of early psychosis: An integrative empirical study.

BACKGROUND: The integration of various domains or levels of analysis (clinical, neurobiological, genetic, etc.) has been a challenge in schizophrenia research. A promising approach is to use the core phenomenological features of the disorder as an organising principle for other levels of analysis. Minimal self-disturbance (fragility in implicit first-person perspective, presence and agency) is emerging as a strong candidate to play this role. This approach was adopted in a previously described theoretical neurophenomenological model that proposed that source monitoring deficits and aberrant salience may be neurocognitive/neurobiological processes that correlate with minimal self-disturbance on the phenomenological level, together playing an aetiological role in the onset of schizophrenia spectrum disorders. The current paper presents full cross-sectional data from the first empirical test of this model. METHODS: Fifty ultra-high risk for psychosis patients, 39 first episode psychosis patients and 34 healthy controls were assessed with a variety of clinical measures, including the Examination of Anomalous Self-Experience (EASE), and neurocognitive and neurophysiological (EEG) measures of source monitoring deficits and aberrant salience. RESULTS: Linear regression indicated that source monitoring (composite score across neurocognitive and neurophysiological measures), with study group as an interaction term, explained 39.8% of the variance in EASE scores (R2 = 0.41, F(3,85) = 14.78, p < 0.001), whereas aberrant salience (composite score) explained only 6% of the variance in EASE scores (R2 = 0.06, F(3,85) = 1.44, p = 0.93). Aberrant salience measures were more strongly related to general psychopathology measures, particularly to positive psychotic symptoms, than to EASE scores. DISCUSSION: A neurophenomenological model of minimal self-disturbance in schizophrenia spectrum disorders may need to be expanded from source monitoring deficits to encompass other relevant constructs such as temporal processing, intermodal/multisensory integration, and hierarchical predictive processing. The cross-sectional data reported here will be expanded with longitudinal analysis in subsequent reports. These data and other related recent research show an emerging picture of neuro-features of core phenomenological aspects of schizophrenia spectrum disorders beyond surface-level psychotic symptoms.

Impaired action self-monitoring and cognitive confidence among ultra-high risk for psychosis and first-episode psychosis patients.

BACKGROUND: Self-monitoring biases and overconfidence in incorrect judgments have been suggested as playing a role in schizophrenia spectrum disorders. Little is known about whether self-monitoring biases may contribute to early risk factors for psychosis. In this study, action self-monitoring (i.e., discrimination between imagined and performed actions) was investigated, along with confidence in judgments among ultra-high risk (UHR) for psychosis individuals and first-episode psychosis (FEP) patients. METHODS: Thirty-six UHR for psychosis individuals, 25 FEP patients and 33 healthy controls (CON) participated in the study. Participants were assessed with the Action memory task. Simple actions were presented to participants verbally or non-verbally. Some actions were required to be physically performed and others were imagined. Participants were asked whether the action was presented verbally or non-verbally (action presentation type discrimination), and whether the action was performed or imagined (self-monitoring). Confidence self-ratings related to self-monitoring responses were obtained. RESULTS: The analysis of self-monitoring revealed that both UHR and FEP groups misattributed imagined actions as being performed (i.e., self-monitoring errors) significantly more often than the CON group. There were no differences regarding performed actions as being imagined. UHR and FEP groups made their false responses with higher confidence in their judgments than the CON group. There were no group differences regarding discrimination between the types of actions presented (verbal vs non-verbal). CONCLUSIONS: A specific type of self-monitoring bias (i.e., misattributing imagined actions with performed actions), accompanied by high confidence in this judgment, may be a risk factor for the subsequent development of a psychotic disorder.

A comparison of cognitive biases between schizophrenia patients with delusions and healthy individuals with delusion-like experiences.

BACKGROUND: The role of psychosis-related cognitive biases (e.g. jumping to conclusions) in a delusion continuum is well-established. Little is known about the role of types of cognitive biases. The aim of this study was to investigate the role of psychosis-related and "Beckian" (i.e. anxiety- and depression-related) cognitive biases assessed with a clinical questionnaire in the delusion continuum and its dimensions. METHODS: Schizophrenia patients with (n=57) and without (n=35) delusions were compared to healthy subjects who had a low (n=53) and high (n=57) level of delusion-like experiences (DLEs) on the Cognitive Biases Questionnaire for Psychosis (CBQp). Delusion dimensions in the clinical sample were assessed with the semi-structured interview PSYRATS. DLEs were measured with the Peters Delusion Inventory (PDI). RESULTS: High DLEs participants scored significantly higher than low DLEs, and patients with delusions scored higher than patients without delusions on the total scores of the CBQp. High DLEs participants scored significantly higher than low DLEs on catastrophisation and JTC. Schizophrenia patients with delusions scored significantly higher when compared to patients without delusions on intentionalising, dichotomous thinking, JTC and emotional reasoning. Patients with delusions and high DLEs participants scored similarly on JTC. Stepwise regression analysis revealed that catastrophising predicted total severity of clinical delusions and JTC predicted the cognitive dimension of clinical delusions. Both JTC and catastrophisation predicted the frequency and conviction associated with DLEs. CONCLUSIONS: Both "Beckian" and psychosis-related cognitive biases may underlie delusions. Different aspects of clinical delusions and delusion-like experiences may be related to different cognitive biases.

Towards a cognitive model of hallucinations in the course of alcohol dependence? A source monitoring-based pilot study.

BACKGROUND: We investigated whether source-monitoring deficits (here a discrimination between imagined and performed actions) underlie hallucinations among patients with a history of hallucinations in the course of their alcohol dependence. METHOD: We assessed 29 patients with alcohol dependence who had no history of hallucinations during their course of alcoholism and 29 patients with a history of at least one episode of hallucinations of any modality during their course of alcohol dependency. The control group consisted of 24 healthy participants. Participants were assessed with an action memory task. Simple actions were presented to the participants verbally or non-verbally. Some actions were performed physically and others were imagined. In the recognition phase, participants were asked whether the action was presented verbally or non-verbally (action presentation type discrimination) and whether the action was performed or imagined (self-monitoring). A confidence score related to self-monitoring responses was also obtained. RESULTS: Alcoholics with a history of hallucinations misremembered imagined actions as perceived ones more frequently than patients without hallucinations, but not the reverse. Only patients with a history of hallucinations committed more errors of this type than healthy subjects. There were no group differences regarding discrimination between an action presentation type. Both clinical groups committed errors with a higher degree of confidence than healthy subjects. CONCLUSIONS: Our results tentatively suggest that a specific type of source-monitoring deficit (i.e., confusing imagery with reality) may be involved in the hallucinations in patients with alcohol dependence. The findings are discussed in the light of a transdiagnostic approach to hallucinations.