The role of expectancies and emotional load in false auditory perceptions among patients with schizophrenia spectrum disorders

Associations of Cognitive Expectancies With Auditory Hallucinations and Hallucinatory-Like Experiences in Patients With Schizophrenia

BACKGROUND

Various neurocognitive models explore perceptual distortions and hallucinations in schizophrenia and the general population. A variant of predictive coding account suggests that strong priors, like cognitive expectancy, may influence perception. This study examines if stronger cognitive expectancies result in more auditory false percepts in clinical and healthy control groups, investigates group differences, and explores the association between false percepts and hallucinations.

STUDY DESIGN

Patients diagnosed with schizophrenia with current auditory hallucinations (n = 51) and without hallucinations (n = 66) and healthy controls (n = 51) underwent the False Perception Task under various expectancy conditions. All groups were examined for the presence and severity of hallucinations or hallucinatory-like experiences.

STUDY RESULTS

We observed a main effect of condition across all groups, ie, the stronger the cognitive expectancy, the greater the ratio of auditory false percepts. However, there was no group effect for the ratio of auditory false percepts. Despite modest pairwise correlations in the hallucinating group, the ratio of auditory false percepts was not predicted by levels of hallucinations and hallucinatory-like experiences in a linear mixed model.

CONCLUSIONS

The current study demonstrates that strong priors in the form of cognitive expectancies affect perception and play a role in perceptual disturbances. There is also a tentative possibility that overreliance on strong priors may be associated with hallucinations in currently hallucinating subjects. Possible, avoidable confounding factors are discussed in detail.

Self-monitoring deficits in schizophrenia: A cross-sectional study of the underlying cognitive mechanisms

BACKGROUND

People diagnosed with schizophrenia share underlying cognitive deficits in self-monitoring (i.e., identifying the source of self-generated behaviours). This study aimed to investigate whether self-monitoring deficits in schizophrenia are due to a cognitive response bias towards external perceptions or a reduced discriminability of imagined and performed actions. We hypothesised that self-monitoring deficits in individuals with schizophrenia are primarily driven by bottom-up processes, leading to a compromised ability to discriminate between internally generated behaviours as opposed to a cognitive response bias towards performed actions.

METHODS

We recruited 333 participants, including 192 with schizophrenia and 141 healthy controls. As part of the Action-Memory Task, participants were instructed to either imagine or physically perform 36 different actions, half of which were presented as pictograms and half as text. In the test phase, participants indicated whether they had performed or imagined each action, whether it appeared in text or pictogram, or whether it was a new action. Using Signal Detection Theory, the study primarily analysed group differences in discriminability and response-bias.

RESULTS

Participants with schizophrenia made significantly more self-monitoring errors than healthy controls. This was primarily due to significantly lower sensitivity, but not a response bias. Whereas recognition memory errors were driven by both lower sensitivity and a response bias.

CONCLUSIONS

The findings suggest that self-monitoring in schizophrenia was specifically impaired by a compromised discriminability of imagined and performed events and an inability to appropriately compensate by adjusting decision-thresholds. Implications on the role of bottom-up and top-down cognitive mechanisms are discussed.

Cognitive correlates of auditory hallucinations in schizophrenia spectrum disorders

Auditory hallucinations (AHs) are one of the central symptoms of schizophrenia spectrum disorders (SSD). Current cognitive models of AH implicate source monitoring, top-down processes, and inhibitory control. However, research combining these processes is limited. Our study aimed to examine how source monitoring bias, top-down processes, and inhibitory control contribute to AHs in individuals with SSD. Eighty seven patients (aged 18-45 years) with SSD were included in the analyses. Participants completed cognitive tasks assessing source monitoring (Action Memory Task), top-down processes (False Perception Task; FPT), and inhibitory control (Auditory Go/NoGo task). AH was positively associated with response bias on the FPT. Correlations between AH and the other cognitive tasks were nonsignificant. Source monitoring errors correlated positively with response bias measures and negatively with Hits on the FPT. PANSS total score was positively correlated with source monitoring bias and False Alarms on the Go/NoGo task. The severity of disorganized symptoms was related to Source Monitoring Errors and False Alarms in the Go/NoGo task. Negative symptoms were associated with Hits and False Alarms in the Go/NoGo task. Future studies are necessary to further elucidate the relationships between different cognitive processes that may be related to clinical symptoms of psychosis.

Phantom phone signals and other hallucinatory-like experiences: Investigation of similarities and differences

Phantom Phone Signals (PPS) and other hallucinatory-like experiences (HLEs) are perceptual anomalies that are commonly reported in the general population. Both phenomena concern the same sensory modality, but PPS are restricted to smartphone use. The current study aimed to assess similarities and differences between these types of anomalies in relation to general psychopathology, metacognitive beliefs about perception, smartphone dependence, and susceptibility to top-down influences on perception. We analyzed data from a Polish community sample (N = 236, aged 18-69). We used questions pertaining to PPS, a questionnaire pertaining to HLEs (Multi-Modality Unusual Sensory Experiences Questionnaire), and other variables of interest (Symptom Checklist-27-plus, Mobile Phone Problematic Use Scale, and the Beliefs about Perception Questionnaire). Additionally, a false-perception task manipulating cognitive expectancy (i.e., a visual cue associated with auditory stimuli vs. no visual cue) was devised to measure top-down influences on perception. Regression analyses showed that only top-down beliefs about perception predicted both PPS and HLEs. Smartphone dependency proved to be a stronger predictor of PPS than other measured variables, whereas for HLEs, general psychopathology was the strongest predictor. Current results suggest that despite sharing some mechanisms, PPS and HLEs may have independent underlying factors.

Predictive waves in the autism-schizophrenia continuum: A novel biobehavioral model

The brain is a predictive machine. Converging data suggests a diametric predictive strategy from autism spectrum disorders (ASD) to schizophrenic spectrum disorders (SSD). Whereas perceptual inference in ASD is rigidly shaped by incoming sensory information, the SSD population is prone to overestimate the precision of their priors' models. Growing evidence considers brain oscillations pivotal biomarkers to understand how top-down predictions integrate bottom-up input. Starting from the conceptualization of ASD and SSD as oscillopathies, we introduce an integrated perspective that ascribes the maladjustments of the predictive mechanism to dysregulation of neural synchronization. According to this proposal, disturbances in the oscillatory profile do not allow the appropriate trade-off between descending predictive signal, overweighted in SSD, and ascending prediction errors, overweighted in ASD. These opposing imbalances both result in an ill-adapted reaction to external challenges. This approach offers a neuro-computational model capable of linking predictive coding theories with electrophysiological findings, aiming to increase knowledge on the neuronal foundations of the two spectra features and stimulate hypothesis-driven rehabilitation/research perspectives.

The Indirect Effect of Trauma via Cognitive Biases and Self-Disturbances on Psychotic-Like Experiences

Although self-disturbances (SD) are considered to be a core psychopathological feature of schizophrenia spectrum disorders, there is still insufficient empirical data on the mechanisms underlying these anomalous self-experiences. The aim of the present study was to test a hypothesized model in which cognitive biases and exposure to traumatic life events are related to the frequency of SD which, in turn, contribute to the frequency of psychotic-like experiences (PLEs). Our sample consisted of 193 Polish young adults from the general population (111 females; 18-35 years of age, M = 25.36, SD = 4.69) who experience frequent PLEs. Participants were interviewed for PLEs, SD and social functioning as well as completed self-reported questionnaires and behavioral tasks that measure cognitive biases (e.g., safety behaviors, attention to threat, external attribution, jumping to conclusion, source monitoring, overperceptualization). The model was tested using path analysis with structural equation modeling. All of the hypothesized relationships were statistically significant and our model fit the data well [χ²(23) = 31.201; p = 0.118; RMSEA = 0.043 (90% CI = 0.00-0.078), CFI = 0.985, SRMR = 0.041, TLI = 0.976]. The results revealed a significant indirect effect of traumatic life events on PLEs through SD and self-reported cognitive biases. However, performance-based cognitive biases measured with three behavioral tasks were unrelated to SD and PLEs. The frequency of SD explained a substantial part (43.1%) of the variance in PLEs. Further studies with longitudinal designs and clinical samples are required to verify the predictive value of the model.