Illness insight and neurophysiological error-processing deficits in schizophrenia

Impaired insight and error-monitoring deficits among outpatients with attenuated psychosis syndrome and first-episode psychosis

We aimed to determine the relationship between electrophysiological signatures of error monitoring and clinical insight among outpatients with attenuated psychosis syndrome (APS) and first-episode psychosis (FEP). Error-related negativity (ERN), error positivity (Pe), and correct response negativity (CRN) were recorded during a modified flanker task for patients with FEP (n = 32), APS individuals (n = 58), and healthy controls (HC, n = 49). Clinical insight was measured using the Schedule of Assessment of Insight (SAI) and included awareness of illness (SAI-illness), relabeling of specific symptoms (SAI-symptoms), and treatment compliance (SAI-treatment). Compared with HC, patients with FEP showed smaller ERN (p < 0.001) and Pe (p = 0.011) amplitudes and individuals with APS showed smaller ERN amplitude (p = 0.009). No significant difference in CRN amplitude was observed among the groups. A smaller negative amplitude of ERN correlated with a lower score on SAI-symptoms (b = -0.032, 95% CI: 0.062 to -0.002, p = 0.035) and a decreased total score of SAI (b = -0.096, 95% CI: 0.182 to -0.010, p = 0.029). This links were adjusted for age, education, and diagnosis (a dummy variable with FEP = 1 and APS = 0), and was independent of positive symptoms. SAI-illness was predominantly influenced by diagnosis, whereas SAI-treatment was additionally affected by disorganized communications. Neither Pe nor CRN amplitude exhibited an association with clinical insight. Unconscious error detection, as indicated by ERN, may aid individuals at the preliminary stage of psychosis in recognizing the unusual symptoms.

Beyond a blunted ERN - Biobehavioral correlates of performance monitoring in schizophrenia

Cognitive deficits are well documented in schizophrenia. Here, we reviewed alterations in performance monitoring as potential marker of cognitive deficits in schizophrenia. We found that performance monitoring alterations in schizophrenia are specific to early (indexed by blunted error-related negativity (ERN)) and late (reflected in blunted error positivity (Pe)) internal error processing, while external performance feedback processing in simple response feedback tasks is relatively preserved. We propose, that these performance monitoring deficits may best be interpret as one aspect of disrupted theta band (4-8 Hz) oscillations over medial frontal recordings sites. Midfrontal theta dynamics are an increasingly established direct neural index of the recruitment of cognitive control and are impaired in several clinical populations. While theta-related ERPs (the ERN) may be an easy to assess marker of cognitive deficits in schizophrenia, further work investigating the trial-by-trial dynamics of theta in both the time and time-frequency domain is needed to parse cognitive deficits in schizophrenia into finer levels of detail and evaluate theta modulation as a therapeutic tool.

Pathways from performance monitoring to negative symptoms and functional outcomes in psychotic disorders

BACKGROUND

Performance monitoring entails rapid error detection to maintain task performance. Impaired performance monitoring is a candidate pathophysiological process in psychotic disorders, which may explain the broader deficit in executive function and its known associations with negative symptoms and poor functioning. The current study models cross-sectional pathways bridging neurophysiological measures of performance monitoring with executive function, symptoms, and functioning.

METHODS

Data were from the 20-year assessment of the Suffolk County Mental Health Project. Individuals with psychotic disorders (N = 181) were originally recruited from inpatient psychiatric facilities. Data were also collected from a geographically and demographically matched group with no psychosis history (N = 242). Neural measures were the error-related negativity (ERN) and error positivity (Pe). Structural equation modeling tested mediation pathways.

RESULTS

Blunted ERN and Pe in the clinical cohort related to impaired executive function (r = 0.26-0.35), negative symptom severity (r = 0.17-0.25), and poor real-world functioning (r = 0.17-0.19). Associations with executive function were consistent across groups. Multiple potential pathways were identified in the clinical cohort: reduced ERN to inexpressivity was mediated by executive function (β = 0.10); reduced Pe to global functioning was mediated by executive function and avolition (β = 0.10).

CONCLUSIONS

This supports a transdiagnostic model of psychotic disorders by which poor performance monitoring contributes to impaired executive function, which contributes to negative symptoms and poor real-world functioning. If supported by future longitudinal research, these pathways could inform the development of targeted interventions to address cognitive and functional deficits that are central to psychotic disorders.

A higher degree of insight impairment in stabilized schizophrenia patients is associated with reduced cardiac vagal tone as indexed by resting-state high-frequency heart rate variability

Varying degrees of impaired clinical insight in schizophrenia differentially impact medication adherence and clinical outcomes, prompting in-depth investigations of the deficits. Research is scarce on the differences in peripheral physiological markers between varying degrees of impaired insight. The aims of this study were to examine the differences in (1) resting-state high-frequency heart rate variability (HF-HRV) and (2) crucial clinical outcomes between schizophrenia patients with varying degrees of insight impairment as measured by the Positive and Negative Syndrome Scale (PANSS) item G12 (lack of judgment and insight). The study recruited a sample of 95 stabilized schizophrenia patients with insight impairment. Patients were divided into 2 groups of either minimal insight impairment (n = 25, PANSS G12 = 2-3) or moderate-to-severe insight impairment (n = 70, PANSS G12 ≥ 4). Patients with moderate-to-severe insight impairment displayed lower HF-HRV, clinician-rated psychosocial function, medication adherence, and working memory capacity, and higher self-reported psychosocial function and life quality, but comparable cognitive insight compared to those with minimal insight impairment. A logistic regression model predicted moderate-to-severe insight impairment based on HF-HRV values at the optimal cut-off point of 3.655, with the sensitivity and specificity 84% and 72%, respectively. HF-HRV seems a peripheral marker sensitively reflecting central pathophysiology implicated in insight impairment of schizophrenia.

Self-perception of mental illness, and subjective and objective cognitive functioning in people with schizophrenia

Background: People with schizophrenia may have a negative self-perception of mental illness. However, the relationship between the self-perception of illness and subjective and objective cognitive functioning remains unclear. Method: Thirty-seven people with schizophrenia were enrolled in the study group. All subjects completed self-reported self-perception of mental illness questionnaires (Birchwood Insight Scale [BIS], Internalized Stigma of Mental Illness [ISMI]), subjective cognitive functioning (Scale to Investigate Cognition in Schizophrenia [SSTICS]) and objective cognitive functioning (Luria Nebraska Neuropsychological Battery [LNNB]). Results: Spearman's rank analysis showed that awareness of illness (domain of insight) was positively associated with most domains of SSTICS and ISMI. Total insight was positively correlated with alienation (domain of ISMI).  Need for treatment (domain of insight) was negatively correlated with stigma resistance (domain of ISMI). Awareness of symptoms (domain of insight) and total insight were negatively associated with receptive speech and arithmetic (LNNB subtest), respectively. ISMI was positively correlated with most domains of SSTICS, but not with LNNB. The group with good insight had higher scores in attention (domain of SSTICS) and total SSTICS and alienation, stereotype endorsement, social withdrawal (domains of ISMI) and total ISMI than the group with poor insight. The group with mild to moderate internalized stigma had higher scores in explicit memory, attention, language, praxia (domains of SSTICS) and total SSTICS than the group with no internalized stigma. Conclusion: We identified that awareness of illness (domain of insight), internalized stigma were significantly associated with most domains of SSTICS, but not with LNNB. Total insight and awareness of symptoms (domain of insight) were significantly associated with receptive speech and arithmetic (LNNB subtest), respectively. Schizophrenia with higher insight or more internalized stigma reported more subjective cognitive impairment. Future studies with larger samples involving follow up are necessary to verify our findings and extend the applicability.

ERP indices of performance monitoring and feedback processing in psychosis: A meta-analysis

BACKGROUND

Although individuals with, or at risk for, psychotic disorders often show difficulties with performance monitoring and feedback processing, findings from studies using event-related potentials (ERPs) to index these processes are not consistent. This meta-analytic review focused on studies of two different indexes of performance monitoring, the early error-related negativity (ERN; n = 25) and the later error positivity (Pe; n = 17), and one index of feedback processing, the feedback negativity (FN; n = 6).

METHODS

We evaluated whether individuals (1) with psychotic disorders, or (2) at heightened risk for these disorders differ from healthy controls in available studies of the ERN, Pe, and FN.

RESULTS

There was a significant, large ERN reduction in those with psychosis (g = -0.96) compared to controls, and a significant, moderate ERN reduction in those at-risk (g = -0.48). In contrast, there were uniformly non-significant, small between-group differences for Pe and FN (gs ≤ |0.16|).

CONCLUSIONS

The results reveal a differential pattern of impairment in psychosis. Early performance monitoring (ERN) impairments are substantial among those with psychotic disorders in general and may be a useful vulnerability indicator for these disorders. However, later performance monitoring (Pe) and basic feedback processing (FN) appear to be relatively spared in psychosis.

Insight in schizophrenia spectrum disorders: relationship with behavior, mood and perceived quality of life, underlying causes and emerging treatments

Poor insight in schizophrenia is prevalent across cultures and phases of illness. In this review, we examine the recent research on the relationship of insight with behavior, mood and perceived quality of life, on its complex roots, and on the effects of existing and emerging treatments. This research indicates that poor insight predicts poorer treatment adherence and therapeutic alliance, higher symptom severity and more impaired community function, while good insight predicts a higher frequency of depression and demoralization, especially when coupled with stigma and social disadvantage. This research also suggests that poor insight may arise in response to biological, experiential, neuropsychological, social-cognitive, metacognitive and socio-political factors. Studies of the effects of existing and developing treatments indicate that they may influence insight. In the context of earlier research and historical models, these findings support an integrative model of poor insight. This model suggests that insight requires the integration of information about changes in internal states, external circumstances, others' perspectives and life trajectory as well as the multifaceted consequences and causes of each of those changes. One implication is that treatments should, beyond providing education, seek to assist persons with schizophrenia to integrate the broad range of complex and potentially deeply painful experiences which are associated with mental illness into their own personally meaningful, coherent and adaptive picture.

Validating dimensions of psychosis symptomatology: Neural correlates and 20-year outcomes

Heterogeneity of psychosis presents significant challenges for classification. Between 2 and 12 symptom dimensions have been proposed, and consensus is lacking. The present study sought to identify uniquely informative models by comparing the validity of these alternatives. An epidemiologic cohort of 628 first-admission inpatients with psychosis was interviewed 6 times over 2 decades and completed an electrophysiological assessment of error processing at year 20. We first analyzed a comprehensive set of 49 symptoms rated by interviewers at baseline, progressively extracting from 1 to 12 factors. Next, we compared the ability of resulting factor solutions to (a) account for concurrent neural dysfunction and (b) predict 20-year role, social, residential, and global functioning, and life satisfaction. A four-factor model showed incremental validity with all outcomes, and more complex models did not improve explanatory power. The 4 dimensions-reality distortion, disorganization, inexpressivity, and apathy/asociality-were replicable in 5 follow-ups, internally consistent, stable across assessments, and showed strong discriminant validity. These results reaffirm the value of separating disorganization and reality distortion, are consistent with recent findings distinguishing inexpressivity and apathy/asociality, and suggest that these 4 dimensions are fundamental to understanding neural abnormalities and long-term outcomes in psychosis. (PsycINFO Database Record

A trans-diagnostic perspective on obsessive-compulsive disorder

Progress in understanding the underlying neurobiology of obsessive-compulsive disorder (OCD) has stalled in part because of the considerable problem of heterogeneity within this diagnostic category, and homogeneity across other putatively discrete, diagnostic categories. As psychiatry begins to recognize the shortcomings of a purely symptom-based psychiatric nosology, new data-driven approaches have begun to be utilized with the goal of solving these problems: specifically, identifying trans-diagnostic aspects of clinical phenomenology based on their association with neurobiological processes. In this review, we describe key methodological approaches to understanding OCD from this perspective and highlight the candidate traits that have already been identified as a result of these early endeavours. We discuss how important inferences can be made from pre-existing case-control studies as well as showcasing newer methods that rely on large general population datasets to refine and validate psychiatric phenotypes. As exemplars, we take 'compulsivity' and 'anxiety', putatively trans-diagnostic symptom dimensions that are linked to well-defined neurobiological mechanisms, goal-directed learning and error-related negativity, respectively. We argue that the identification of biologically valid, more homogeneous, dimensions such as these provides renewed optimism for identifying reliable genetic contributions to OCD and other disorders, improving animal models and critically, provides a path towards a future of more targeted psychiatric treatments.

Impaired error processing in late-phase psychosis: Four-year stability and relationships with negative symptoms

Error processing is impaired in psychosis, and numerous event-related potential studies have found reductions in the error-related negativity (ERN) and, more recently, the error positivity (Pe). The stability of reduced ERN/Pe in psychosis, however, is unknown. In a previous cross-sectional report, reduced ERN was associated with negative symptom severity and reduced Pe with a diagnosis of schizophrenia versus other psychosis. Here, we test the stability of impaired error processing over a four-year follow-up and relationships with subdimensions of negative symptoms. The ERN and Pe were recorded from individuals with psychotic disorders twice: 79 individuals were assessed 15years after first hospitalization, and 69 were assessed at 19years; 59 (26 with schizophrenia, 33 with other psychotic disorders) had data at both assessments. At 19years the Pe was blunted in schizophrenia. The ERN and Pe exhibited temporal stability over the four years (r=0.59 and 0.60, respectively). Reduced ERN and Pe correlated with the negative symptom subdimensions of inexpressivity and avolition, respectively, and not with psychotic or disorganized symptoms. Moreover, 15-year ERN predicted an increase in inexpressivity by year 19. No evidence was found for the reverse: negative symptoms did not predict change in ERN/Pe. Similar to non-clinical samples, the ERN and Pe show impressive four-year stability in late-phase psychosis. The ERN and Pe are promising neural measures for capturing individual differences in psychotic disorders, particularly with regard to negative symptomatology. They may prove to be useful clinically for forecasting illness course and as treatment targets.

Error-related brain activity in the age of RDoC: A review of the literature

The ability to detect and respond to errors is critical to successful adaptation to a changing environment. The error-related negativity (ERN), an event-related potential (ERP) component, is a well-validated neural response to errors and reflects the error monitoring activity of the anterior cingulate cortex (ACC). Additionally, the ERN is implicated in several processes key to adaptive functioning. Abnormalities in error-related brain activity have been linked to multiple forms of psychopathology and individual differences. As such, the component is likely to be useful in NIMH's Research Domain Criteria (RDoC) initiative to establish biologically-meaningful dimensions of psychological dysfunction, and currently appears as a unit of measurement in three RDoC domains: Positive Valence Systems, Negative Valence Systems, and Cognitive Systems. In this review paper, we introduce the ERN and discuss evidence related to its psychometric properties, as well as important task differences. Following this, we discuss evidence linking the ERN to clinically diverse forms of psychopathology, as well as the implications of one unit of measurement appearing in multiple RDoC dimensions. And finally, we discuss important future directions, as well as research pathways by which the ERN might be leveraged to track the ways in which dysfunctions in multiple neural systems interact to influence psychological well-being.

High cortisol awakening response is associated with impaired error monitoring and decreased post-error adjustment

The cortisol awakening response (CAR), a rapid increase in cortisol levels following morning awakening, is an important aspect of hypothalamic-pituitary-adrenocortical axis activity. Alterations in the CAR have been linked to a variety of mental disorders and cognitive function. However, little is known regarding the relationship between the CAR and error processing, a phenomenon that is vital for cognitive control and behavioral adaptation. Using high-temporal resolution measures of event-related potentials (ERPs) combined with behavioral assessment of error processing, we investigated whether and how the CAR is associated with two key components of error processing: error detection and subsequent behavioral adjustment. Sixty university students performed a Go/No-go task while their ERPs were recorded. Saliva samples were collected at 0, 15, 30 and 60 min after awakening on the two consecutive days following ERP data collection. The results showed that a higher CAR was associated with slowed latency of the error-related negativity (ERN) and a higher post-error miss rate. The CAR was not associated with other behavioral measures such as the false alarm rate and the post-correct miss rate. These findings suggest that high CAR is a biological factor linked to impairments of multiple steps of error processing in healthy populations, specifically, the automatic detection of error and post-error behavioral adjustment. A common underlying neural mechanism of physiological and cognitive control may be crucial for engaging in both CAR and error processing.