Is it me? Verbal self-monitoring neural network and clinical insight in schizophrenia

Global neural self-disturbance in schizophrenia: A systematic fMRI review

There is a general consensus that schizophrenia (SZ) is characterized by major changes in the sense of self. Phenomenological studies suggest that these changes in the sense of self stem from a basic disturbance, hence the term 'basic self-disturbance'. While imaging studies demonstrate changes in various regions during self-focused tasks, the exact neural correlates of such basic self-disturbances remain unclear. If the self-disturbance is indeed basic and thereby underlies all other symptoms, one would expect it to be related to more global rather than local changes in the brain. Testing this hypothesis, we conducted a systematic review of fMRI studies on self in SZ. Our main findings are 1. Abnormal activity related to the self can be observed in a variety of different regions ranging from higher-order transmodal to lower-order unimodal regions, 2. These findings hold true across different tasks including self-reflection, self-referentiality, and self-agency, and 3. The global neural abnormalities related to the self in SZ correspond to all layers of the self, predominantly the mental and exteroceptive self. Such global neural disturbance of self converges well with the basic self-disturbance as described in phenomenology.

Neuropsychological dimensions related to alterations of verbal self-monitoring neural networks in schizophrenic language: systematic review

Although schizophrenia has traditionally been interpreted as a disorder of thought, contemporary perspectives suggest that it may be more appropriate to conceptualize it as a disorder of language connectivity. The linguistic anomalies present in schizophrenia possess distinctive characteristics that, despite certain connections, are not comparable to aphasic disorders. It is proposed that these anomalies are the result of dysfunctions in verbal self-monitoring mechanisms, which may influence other neuropsychological dimensions. This study set out to examine the neuropsychological dimensions associated with alterations in the neural networks of verbal self-monitoring in schizophrenic language, based on the scientific evidence published to date. Exhaustive searches were conducted in PubMed, Web of Science, and Scopus to identify magnetic resonance studies that evaluated verbal self-monitoring mechanisms in schizophrenia. Of a total of 133 articles identified, 22 were selected for qualitative analysis. The general findings indicated alterations in frontotemporoparietal networks and in systems such as the insula, amygdala, anterior cingulate cortex, putamen, and hippocampus. Despite the heterogeneity of the data, it is concluded that language plays a fundamental role in schizophrenia and that its alterations are linked with other neuropsychological dimensions, particularly emotional and perceptual ones.

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.

The effects of acute dopamine depletion on resting-state functional connectivity in healthy humans

Alpha-methyl-para-tyrosine (AMPT), a competitive inhibitor of tyrosine hydroxylase, can be used to deplete endogenous dopamine in humans. We examined how AMPT-induced dopamine depletion alters resting-state functional connectivity of the basal ganglia, and canonical resting-state networks, in healthy humans. Fourteen healthy participants (8 females; age [mean ± SD] = 27.93 ± 9.86) completed the study. Following dopamine depletion, the caudate showed reduced connectivity with the medial prefrontal cortex (mPFC) (Cohen's d = 1.89, p<.0001). Moreover, the caudate, putamen, globus pallidus, and midbrain all showed reduced connectivity with the occipital cortex (Cohen's d = 1.48-1.90; p<.0001-0.001). Notably, the dorsal caudate showed increased connectivity with the sensorimotor network (Cohen's d = 2.03, p=.002). AMPT significantly decreased self-reported motivation (t(13)=4.19, p=.001) and increased fatigue (t(13)=4.79, p=.0004). A greater increase in fatigue was associated with a greater reduction in connectivity between the substantia nigra and the mPFC (Cohen's d = 3.02, p<.00001), while decreased motivation was correlated with decreased connectivity between the VTA and left sensorimotor cortex (Cohen's d = 2.03, p=.00004). These findings help us to better understand the role of dopamine in basal ganglia function and may help us better understand neuropsychiatric diseases where abnormal dopamine levels are observed.

Expectancy changes the self-monitoring of voice identity

Self‐voice attribution can become difficult when voice characteristics are ambiguous, but functional magnetic resonance imaging (fMRI) investigations of such ambiguity are sparse. We utilized voice‐morphing (self‐other) to manipulate (un‐)certainty in self‐voice attribution in a button‐press paradigm. This allowed investigating how levels of self‐voice certainty alter brain activation in brain regions monitoring voice identity and unexpected changes in voice playback quality. FMRI results confirmed a self‐voice suppression effect in the right anterior superior temporal gyrus (aSTG) when self‐voice attribution was unambiguous. Although the right inferior frontal gyrus (IFG) was more active during a self‐generated compared to a passively heard voice, the putative role of this region in detecting unexpected self‐voice changes during the action was demonstrated only when hearing the voice of another speaker and not when attribution was uncertain. Further research on the link between right aSTG and IFG is required and may establish a threshold monitoring voice identity in action. The current results have implications for a better understanding of the altered experience of self‐voice feedback in auditory verbal hallucinations.

Involuntary Autobiographical Memories in Schizophrenia: Characteristics and Conditions of Elicitation

Involuntary autobiographical memories are mental representations of personally experienced past events that come to mind spontaneously, with no preceding attempt to recall them. They have been showed to be more frequent and more emotional in the psychosis continuum. Although schizophrenia is strongly associated with thought disorders, including cognitive intrusions of thought, images, semantic knowledge, research on patients' involuntary autobiographical memories is limited. We undertook two studies to compare involuntary and voluntary remembering in schizophrenia and the conditions in which involuntary memories occurs in those patients, both in daily life (n = 40), using a diary method, and in an experimental context (n = 50). Overall, results showed that the conditions of elicitation of involuntary memories differ in patients, as patients were more sensitive to memory triggers, especially internal triggers, in comparison to controls. Relatedly, patients' involuntary memories-mostly related to mundane events with low emotional load-were experienced more frequently. Although patients' involuntary and voluntary memories were less clear, more poorly contextualized and associated with a lower belief in occurrence than those of controls, patients considered them as more central to the self, in comparison to controls. The results are discussed in relation to patients' self-reflective impairments.

Social Perception Predicts Awareness of Illness in Persons With Schizophrenia

Lack of clinical insight in patients with schizophrenia is an obstacle to optimal treatment. Social cognition is one of several variables central to insight deficits in schizophrenia. The aim of this study was to investigate clinical insight in relation to one domain of social cognition, social perception, while controlling for effects of nonsocial cognition and symptom severity. Clinical insight was measured in 55 patients with schizophrenia or schizoaffective disorder, using the Birchwood Insight Scale. Relationships across domains were used to assess social perception. Social perception predicted one of three subscales of clinical insight, "awareness of illness," and was the only unique contributor to this subscale. This indicates that social perception is linked to clinical insight through awareness of illness. More research is needed to fully understand the relationship between social and nonsocial cognition and symptoms in relation to clinical insight.

Diminished self-monitoring in hallucinations - Aberrant anterior insula connectivity differentiates auditory hallucinations in schizophrenia from subjective tinnitus

Auditory hallucinations in schizophrenia (SCZ-AH) and subjective tinnitus (TN) are two conditions that share a superficial resemblance, namely the presence of phantom sounds produced by the brain. A crucial difference between them lies in the self-processing of the phantom signals, which is intact in TN patients but lost in SCZ-AH. Our study sets out to investigate the potential neural mechanisms for this crucial psychotic symptom of SCZ-AH under the framework of self. We gathered resting-state fMRI data from three participant groups: SCZ-AH, TN and healthy controls. Focusing on predefined self-related regions-of-interest, we found that SCZ-AH had reduced degree centrality in the right anterior insula (rAI) compared to both TN and healthy controls. Further functional connectivity analysis showed a reduced connectivity between the rAI and right superior temporal gyrus. Our finding indicates that compromised self-processing in SCZ-AH could be due to aberrant connectivity in rAI, which interacted with the decreased connectivity between rAI and auditory cortex, and jointly contributed to the misattribution of the source of the phantom sound. Our findings provided preliminary evidence for the neural mechanism of self-disorder underlying SCZ-AH, and could provide implications for investigating other modalities of hallucinations in schizophrenia.

Brain areas associated with clinical and cognitive insight in psychotic disorders: A systematic review and meta-analysis

In the past years, ample interest in brain abnormalities related to clinical and cognitive insight in psychosis has contributed several neuroimaging studies to the literature. In the current study, published findings on the neural substrates of clinical and cognitive insight in psychosis are integrated by performing a systematic review and meta-analysis. Coordinate-based meta-analyses were performed with the parametric coordinate-based meta-analysis approach, non-coordinate based meta-analyses were conducted with the metafor package in R. Papers that could not be included in the meta-analyses were systematically reviewed. Thirty-seven studies were retrieved, of which 21 studies were included in meta-analyses. Poorer clinical insight was related to smaller whole brain gray and white matter volume and gray matter volume of the frontal gyri. Cognitive insight was predominantly positively associated with structure and function of the hippocampus and ventrolateral prefrontal cortex. Impaired clinical insight is not associated with abnormalities of isolated brain regions, but with spatially diffuse global and frontal abnormalities suggesting it might rely on a range of cognitive and self-evaluative processes. Cognitive insight is associated with specific areas and appears to rely more on retrieving and integrating self-related information.

Associating Psychotic Symptoms with Altered Brain Anatomy in Psychotic Disorders Using Multidimensional Item Response Theory Models

Reduced cortical thickness has been demonstrated in psychotic disorders, but its relationship to clinical symptoms has not been established. We aimed to identify the regions throughout neocortex where clinical psychosis manifestations correlate with cortical thickness. Rather than perform a traditional correlation analysis using total scores on psychiatric rating scales, we applied multidimensional item response theory to identify a profile of psychotic symptoms that was related to a region where cortical thickness was reduced. This analysis was performed using a large population of probands with psychotic disorders (N = 865), their family members (N = 678) and healthy volunteers (N = 347), from the 5-site Bipolar-Schizophrenia Network for Intermediate Phenotypes. Regional cortical thickness from structural magnetic resonance scans was measured using FreeSurfer; individual symptoms were rated using the Positive and Negative Syndrome Scale, Montgomery-Asberg Depression Rating Scale, and Young Mania Rating Scale. A cluster of cortical regions whose thickness was inversely related to severity of psychosis symptoms was identified. The regions turned out to be located contiguously in a large region of heteromodal association cortex including temporal, parietal and frontal lobe regions, suggesting a cluster of contiguous neocortical regions important to psychosis expression. When we tested the relationship between reduced cortical surface area and high psychotic symptoms we found no linked regions describing a related cortical set.

A Functional Neuroimaging Meta-Analysis of Self-Related Processing in Schizophrenia

Background: Schizophrenia is characterized by self-disturbances, including impaired self-evaluation abilities and source monitoring. The cortical midline structures (e.g., medial prefrontal cortex, anterior and posterior cingulate cortex, and precuneus) and the temporoparietal junction are known to play a key role in self-related processing. In theory, self-disturbances in schizophrenia may arise from impaired activity in these regions. We performed a functional neuroimaging meta-analysis to verify this hypothesis. Methods: A literature search was performed with PubMed and Google Scholar to identify functional neuroimaging studies examining the neural correlates of self-processing in schizophrenia, using self-other or source monitoring paradigms. Fourteen studies were retrieved, involving 245 patients and 201 controls. Using peak coordinates to recreate an effect-size map of contrast results, a standard random-effects variance weighted meta-analysis for each voxel was performed with the Seed-based d Mapping software. Results: During self-processing, decreased activations were observed in schizophrenia patients relative to controls in the bilateral thalamus and the left dorsal anterior cingulate cortex (dACC) and dorso-medial prefrontal cortex. Importantly, results were homogeneous across studies, and no publication bias was observed. Sensitivity analyses revealed that results were replicable in 93-100% of studies. Conclusion: The current results partially support the hypothesized impaired activity of cortical midline brain regions in schizophrenia during self-processing. Decreased activations were observed in the dACC and dorsomedial prefrontal cortex, which are involved in cognitive control and/or salience attribution, as well as decision-making, respectively. These alterations may compromise patients' ability to direct their attention toward themselves and/or others and to make the decision whether a certain trait applies to one's self or to someone else. In addition, decreased activations were observed in the thalamus, which is not a core region of the default-mode network, and is involved in information integration. These thalamic alterations may compromise self-coherence in schizophrenia.

Insight and emotion regulation in schizophrenia: A brain activation and functional connectivity study

Background

Insight is impaired in the majority of schizophrenia patients. The exact neural correlates of impaired insight remain unclear. We assume that the ability to regulate emotions contributes to having good clinical insight, as patients should be able to regulate their emotional state in such a way that they can adapt adequately in order to cope with impaired functioning and negative stigma associated with a diagnosis of schizophrenia. Numerous studies have shown emotional dysregulation in schizophrenia. We investigated the association between insight and brain activation and connectivity during emotion regulation.

Methods

Brain activation during emotion regulation was measured with functional MRI in 30 individuals with schizophrenia. Two emotion regulation strategies were examined: cognitive reappraisal and expressive suppression. Clinical insight was measured with the Schedule for the Assessment of Insight – Expanded, and cognitive insight was measured with the Beck Cognitive Insight Scale. Whole brain random effects multiple regression analyses were conducted to assess the relation between brain activation during emotion regulation and insight. Generalized psychophysiological interaction (gPPI) was used to investigate the relation between task-related connectivity and insight.

Results

No significant associations were found between insight and neural correlates of cognitive reappraisal. For clinical insight and suppression, significant positive associations were found between symptom relabeling and activation in the left striatum, thalamus and insula, right insula and caudate, right pre- and postcentral gyrus, left superior occipital gyrus and cuneus and right middle and superior occipital gyrus and cuneus. Furthermore, reduced clinical insight was associated with more connectivity between midline medial frontal gyrus and right middle occipital gyrus. For cognitive insight and suppression, significant positive associations were found between self-reflectiveness and activation in pre- and postcentral gyrus and left middle cingulate gyrus.

Conclusions

Our results suggest an association between the capacity to relabel symptoms and activation of brain systems involved in cognitive-emotional control and visual processing of negative stimuli. Furthermore, poorer self-reflectiveness may be associated with brain systems subserving control and execution.

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We examined the association between emotion regulation and insight in schizophrenia.

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Patients with poorer insight engage different neural pathways during suppression.

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This finding was strengthened by connectivity measures of corresponding brain areas.

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No relationship between cognitive reappraisal and insight was found.

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.

Distinct pattern of cerebral blood flow alterations specific to schizophrenics experiencing auditory verbal hallucinations with and without insight: a pilot study

Schizophrenia is associated with widespread and complex cerebral blood flow (CBF) disturbance. Auditory verbal hallucinations (AVH) and insight are the core symptoms of schizophrenia. However, to the best of our knowledge, very few studies have assessed the CBF characteristics of the AVH suffered by schizophrenic patients with and without insight. Based on our previous findings, Using a 3D pseudo-continuous ASL (pcASL) technique, we investigated the differences in AVH-related CBF alterations in schizophrenia patients with and without insight. We used statistical parametric mapping (SPM8) and statistical non-parametric mapping (SnPM13) to perform the fMRI analysis. We found that AVH-schizophrenia patients without insight showed an increased CBF in the left temporal pole and a decreased CBF in the right middle frontal gyrus when compared to AVH-schizophrenia patients with insight. Our novel findings suggest that AVH-schizophrenia patients without insight possess a more complex CBF disturbance. Simultaneously, our findings also incline to support the idea that the CBF aberrant in some specific brain regions may be the common neural basis of insight and AVH. Our findings support the mostly current hypotheses regarding AVH to some extent. Although our findings come from a small sample, it provide the evidence that indicate us to conduct a larger study to thoroughly explore the mechanisms of schizophrenia, especially the core symptoms of AVHs and insight.

Voxel-based magnetic resonance imaging investigation of poor and preserved clinical insight in people with schizophrenia

AIM

To define regional grey-matter abnormalities in schizophrenia patients with poor insight (Insight^-), relative to patients with preserved clinical insight (Insight⁺), and healthy controls.

METHODS

Forty stable schizophrenia outpatients (20 Insight^- and 20 Insight⁺) and 20 healthy controls underwent whole brain magnetic resonance imaging (MRI). Insight in all patients was assessed using the Birchwood Insight Scale (BIS; a self-report measure). The two patient groups were pre-selected to match on most clinical and demographic parameters but, by design, they had markedly distinct BIS scores. Voxel-based morphometry employed in SPM8 was used to examine group differences in grey matter volumes across the whole brain.

RESULTS

The three participant groups were comparable in age [F(2,57) = 0.34, P = 0.71] and the patient groups did not differ in age at illness onset [t(38) = 0.87, P = 0.39]. Insight^- and Insight⁺ patient groups also did not differ in symptoms on the Positive and Negative Syndromes scale (PANSS): Positive symptoms [t(38) = 0.58, P = 0.57], negative symptoms [t(38) = 0.61, P = 0.55], general psychopathology [t(38) = 1.30, P = 0.20] and total PANSS scores [t(38) = 0.21, P = 0.84]. The two patient groups, as expected, varied significantly in the level of BIS-assessed insight [t(38) = 12.11, P < 0.001]. MRI results revealed lower fronto-temporal, parahippocampal, occipital and cerebellar grey matter volumes in Insight^- patients, relative to Insight⁺ patients and healthy controls (for all clusters, family-wise error corrected P < 0.05). Insight⁺ patient and healthy controls did not differ significantly (P > 0.20) from each other.

CONCLUSION

Our findings demonstrate a clear association between poor clinical insight and smaller fronto-temporal, occipital and cerebellar grey matter volumes in stable long-term schizophrenia patients.

An integrative model of the impairments in insight in schizophrenia: emerging research on causal factors and treatments

INTRODUCTION

Poor insight, or unawareness of some major aspect of mental illness, is a major barrier to wellness when it interferes with persons seeking out treatment or forming their own understanding of the challenges they face. One barrier to addressing impaired insight is the absence of a comprehensive model of how poor insight develops.

AREAS COVERED

To explore this issue we review how poor insight is the result of multiple phenomena which interfere with the construction of narrative accounts of psychiatric challenges, rather than a single social or biological cause. Expert commentary: We propose an integrative model of poor insight in schizophrenia which involves the interaction of symptoms, deficits in neurocognition, social cognition, metacognition, and stigma. Emerging treatments for poor insight including therapies which focus on the development of metacognition are discussed.