Cognition and communication dysfunctions in early-onset schizophrenia: effect of risperidone

Antipsychotics-induced improvement of cool executive function in individuals living with schizophrenia

Cool executive dysfunction is a crucial feature in people living with schizophrenia which is related to cognition impairment and the severity of the clinical symptoms. Based on electroencephalogram (EEG), our current study explored the change of brain network under the cool executive tasks in individuals living with schizophrenia before and after atypical antipsychotic treatment (before_TR vs. after_TR). 21 patients with schizophrenia and 24 healthy controls completed the cool executive tasks, involving the Tower of Hanoi Task (THT) and Trail-Marking Test A-B (TMT A-B). The results of this study uncovered that the reaction time of the after_TR group was much shorter than that of the before_TR group in the TMT-A and TMT-B. And the after_TR group showed fewer error numbers in the TMT-B than those of the before_TR group. Concerning the functional network, stronger DMN-like linkages were found in the before_TR group compared to the control group. Finally, we adopted a multiple linear regression model based on the change network properties to predict the patient's PANSS change ratio. Together, the findings deepened our understanding of cool executive function in individuals living with schizophrenia and might provide physiological information to reliably predict the clinical efficacy of schizophrenia after atypical antipsychotic treatment.

Detecting formal thought disorder by deep contextualized word representations

Computational linguistics has enabled the introduction of objective tools that measure some of the symptoms of schizophrenia, including the coherence of speech associated with formal thought disorder (FTD). Our goal was to investigate whether neural network based utterance embeddings are more accurate in detecting FTD than models based on individual indicators. The present research used a comprehensive Embeddings from Language Models (ELMo) approach to represent interviews with patients suffering from schizophrenia (N=35) and with healthy people (N=35). We compared its results to the approach described by Bedi et al. (2015), referred to here as the coherence model. Evaluations were also performed by a clinician using the Scale for the Assessment of Thought, Language and Communication (TLC). Using all six TLC questions the ELMo obtained an accuracy of 80% in distinguishing patients from healthy people. Previously used coherence models were less accurate at 70%. The classifying clinician was accurate 74% of the time. Our analysis shows that both ELMo and TLC are sensitive to the symptoms of disorganization in patients. In this study methods using text representations from language models were more accurate than those based solely on the assessment of FTD, and can be used as measures of disordered language that complement human clinical ratings.

Dissecting the neurobiology of linguistic disorganisation and impoverishment in schizophrenia

Schizophrenia provides a quintessential disease model of how disturbances in the molecular mechanisms of neurodevelopment lead to disruptions in the emergence of cognition. The central and often persistent feature of this illness is the disorganisation and impoverishment of language and related expressive behaviours. Though clinically more prominent, the periodic perceptual distortions characterised as psychosis are non-specific and often episodic. While several insights into psychosis have been gained based on study of the dopaminergic system, the mechanistic basis of linguistic disorganisation and impoverishment is still elusive. Key findings from cellular to systems-level studies highlight the role of ubiquitous, inhibitory processes in language production. Dysregulation of these processes at critical time periods, in key brain areas, provides a surprisingly parsimonious account of linguistic disorganisation and impoverishment in schizophrenia. This review links the notion of excitatory/inhibitory (E/I) imbalance at cortical microcircuits to the expression of language behaviour characteristic of schizophrenia, through the building blocks of neurochemistry, neurophysiology, and neurocognition.

Examination of formal thought disorder and its clinical correlates with the Turkish Version of the Thought and Language Disorder Scale (TALD-TR) in schizophrenia

BACKGROUND

Formal thought disorder (FTD) is considered to be a fundamental feature of schizophrenia. This study aims to analyze psychometric properties of the Turkish version of "Thought and Language Disorder Scale (TALD)" and investigate the relationship between FTD and various clinical characteristics in patients with schizophrenia.

METHODS

TALD was adapted into Turkish and applied to a total of 149 participants of which 114 had DSM-5 psychiatric diagnoses (schizophrenia N = 70, mania N = 20, depression N = 24) and 35 were healthy controls. Positive and Negative Syndrome Scale (PANSS), Hamilton Depression Rating Scale, Young Mania Rating Scale, and Clinical Global Impression were administered to detect illness severity.

RESULTS

The principal component analyses revealed that the Turkish version of TALD (TALD-TR) consisted of four factors including the Objective Positive (OP), Subjective Negative (SN), Objective Negative (ON) and Subjective Positive (SP) symptom dimensions which were in line with the original TALD factorial structure. It was concluded that TALD-TR shows strong construct validity and high interrater reliability. The correlation analyses with TALD-TR and PANSS showed that there are positive correlations between the TALD-TR total score and the PANSS total and subscale scores. Each diagnostic group showed the distinct pattern of FTD. The mania group exhibited the highest mean total score in the OP, whereas the schizophrenia group exhibited the highest mean total score in the ON factor. In the schizophrenia group, the severity of FTD correlated positively with duration of illness and negatively with age at onset of illness.

CONCLUSION

Adaptation of TALD into different languages seems to be possible, bringing in an international tool for research on FTD.

Formal thought disorders: from phenomenology to neurobiology

Formal thought disorder (FTD) is present in most psychiatric disorders and in some healthy individuals. In this Review, we present a comprehensive, integrative, and multilevel account of what is known about FTD, covering genetic, cellular, and neurotransmitter effects, environmental influences, experimental psychology and neuropsychology, brain imaging, phenomenology, linguistics, and treatment. FTD is a dimensional, phenomenologically defined construct, which can be clinically subdivided into positive versus negative and objective versus subjective symptom clusters. Because FTDs have been traditionally linked to schizophrenia, studies in other diagnoses are scarce. Aetiologically, FTD is the only symptom under genetic influence in schizophrenia as shown in linkage studies, but familial communication patterns (allusive thinking) have also been associated with the condition. Positive FTDs are related to synaptic rarefication in the glutamate system of the superior and middle lateral temporal cortices. Cortical volume of the left superior temporal gyrus is decreased in patients with schizophrenia who have positive FTD in structural MRI studies and shows reversed hemispheric (right more than left) activation in functional MRI experiments during speech production. Semantic network dysfunction in positive FTD has been demonstrated in experiments of indirect semantic hyperpriming (reaction time). In acute positive FTD, antipsychotics are effective, but a subgroup of patients have treatment-resistant, chronic, positive or negative FTD. Specific psychotherapy as treatment for FTD has not yet been developed. With this solid data on the pathogenesis of FTD, we can now implement clinical studies to treat this condition.

A Brief Assessment of Intelligence Decline in Schizophrenia As Represented by the Difference between Current and Premorbid Intellectual Quotient

Patients with schizophrenia elicit several clinical features, such as psychotic symptoms, cognitive impairment, and subtle decline of intelligence. The latter two features become evident around the onset of the illness, although they may exist even before the disease onset in a substantial proportion of cases. Here, we review the literature concerning intelligence decline (ID) during the progression of schizophrenia. ID can be estimated by comparing premorbid and current intellectual quotient (IQ) by means of the Adult Reading Test and Wechsler Adult Intelligence Scale (WAIS), respectively. For the purpose of brief assessment, we have recently developed the WAIS-Short Form, which consists of Similarities and Symbol Search and well reflects functional outcomes. According to the degree of ID, patients were classified into three distinct subgroups; deteriorated, preserved, and compromised groups. Patients who show deteriorated IQ (deteriorated group) elicit ID from a premorbid level (≥10-point difference between current and premorbid IQ), while patients who show preserved or compromised IQ do not show such decline (<10-point difference). Furthermore, the latter patients were divided into patients with preserved and compromised IQ based on an estimated premorbid IQ score >90 or below 90, respectively. We have recently shown the distribution of ID in a large cohort of schizophrenia patients. Consistent with previous studies, approximately 30% of schizophrenia patients had a decline of less than 10 points, i.e., normal intellectual performance. In contrast, approximately 70% of patients showed deterioration of IQ. These results indicate that there is a subgroup of schizophrenia patients who have mild or minimal intellectual deficits, following the onset of the disorder. Therefore, a careful assessment of ID is important in identifying appropriate interventions, including medications, cognitive remediation, and social/community services.

Can RDoC Help Find Order in Thought Disorder?

Thought disorder is a pernicious and nonspecific aspect of numerous serious mental illnesses (SMIs) and related conditions. Despite decades of empirical research on thought disorder, our present understanding of it is poor, our clinical assessments focus on a limited set of extreme behaviors, and treatments are palliative at best. Applying a Research Domain Criteria (RDoC) framework to thought disorder research offers advantages to explicate its phenotype; isolate its mechanisms; and develop more effective assessments, treatments, and potential cures. In this commentary, we discuss ways in which thought disorder can be understood within the RDoC framework. We propose operationalizing thought disorder within the RDoC construct of language using psycholinguistic sciences, to help objectify and quantify language within individuals; technologically sophisticated paradigms, to allow naturalistic behavioral sampling techniques with unprecedented ecological validity; and computational modeling, to account for a network of interconnected and dynamic linguistic, cognitive, affective, and social functions. We also highlight challenges for understanding thought disorder within an RDoC framework. Thought disorder likely does not occur as an isomorphic dysfunction in a single RDoC construct, but rather, as multiple potential dysfunctions in a network of RDoC constructs. Moreover, thought disorder is dynamic over time and context within individuals. In sum, RDoC is a useful framework to integrate multidisciplinary research efforts aimed at operationalizing, understanding, and ameliorating thought disorder.

Theory of mind in adolescents with early-onset schizophrenia: correlations with clinical assessment and executive functions

OBJECTIVE

We examined Theory of Mind (ToM) abilities in adolescents with early-onset schizophrenia (EOS) and their correlation with clinical findings and Executive Functions (EF).

METHODS

The ToM abilities of 12 adolescents with EOS were compared with those of healthy participants matched in age and educational level. The Moving Shapes Paradigm was used to explore ToM abilities in three modalities: random movement, goal-directed movement and ToM - scored on the dimensions of intentionality, appropriateness and length of each answer. EF was tested using Davidson's Battery and the clinical psychopathology with the Positive and Negative Syndrome Scale (PANSS).

RESULTS

Adolescents with EOS were significantly more impaired than controls in the three dimensions evaluated for the goal-directed and ToM modalities. Regarding the random movement modality, the only difference was in appropriateness (p<0.01). No correlation with age or level of education was evident for ToM skills. Total PANSS score was negatively correlated with appropriateness score for the goal-directed (p=0.02) and ToM modalities (p=0.01). No correlation existed between performance in the ToM Animated Tasks and positive, negative or disorganisation PANSS subscores. No correlations were found among the three scores in the Moving Shapes Paradigm and any measures of the accuracy of the three tasks assessing EF.

CONCLUSION

Our results confirm previous findings of ToM deficits in adult individuals with schizophrenia and attest the severity of these deficits in patients with EOS.

Clinical Characteristics and Predictors of Outcome of Schizophrenia-Spectrum Psychosis in Children and Adolescents: A Systematic Review

OBJECTIVE

Treatment of early-onset schizophrenia spectrum psychosis (EOS) is hampered by limited data on clinical presentation and illness course. We aimed to systematically review the clinical characteristics, diagnostic trajectories, and predictors of illness severity and outcomes of EOS.

METHODS

We conducted a systematic PubMed, PsycINFO, and Embase literature review including studies published from January 1, 1990 to August 8, 2014 of EOS patients with 1) ≥50% nonaffective psychosis cases; 2) mean age of subjects <19 years; 3) clinical samples recruited through mental health services; 4) cross-sectional or prospective design; 5) ≥20 participants at baseline; 6) standardized/validated diagnostic instruments; and 7) quantitative psychotic symptom frequency or severity data. Exploratory analyses assessed associations among relevant clinical variables.

RESULTS

Across 35 studies covering 28 independent samples (n = 1506, age = 15.6 years, age at illness onset = 14.5 years, males = 62.3%, schizophrenia-spectrum disorders = 89.0%), the most frequent psychotic symptoms were auditory hallucinations (81.9%), delusions (77.5%; mainly persecutory [48.5%], referential [35.1%], and grandiose [25.5%]), thought disorder (65.5%), bizarre/disorganized behavior (52.8%), and flat or blunted affect/negative symptoms (52.3%/50.4%). Mean baseline Positive and Negative Syndrome Scale (PANSS)-total, positive, and negative symptom scores were 84.5 ± 10.9, 19.3 ± 4.4 and 20.8 ± 2.9. Mean baseline Clinical Global Impressions-Severity and Children's Global Assessment Scale/Global Assessment of Functioning (CGAS/GAF) scores were 5.0 ± 0.7 and 35.5 ± 9.1. Comorbidity was frequent, particularly posttraumatic stress disorder (34.3%), attention-deficit/hyperactivity and/or disruptive behavior disorders (33.5%), and substance abuse/dependence (32.0%). Longer duration of untreated psychosis (DUP) predicted less CGAS/GAF improvement (p < 0.0001), and poor premorbid adjustment and a diagnosis of schizophrenia predicted less PANSS negative symptom improvement (p = 0.0048) at follow-up. Five studies directly comparing early-onset with adult-onset psychosis found longer DUP in EOP samples (18.7 ± 6.2 vs. 5.4 ± 3.1 months, p = 0.0027).

CONCLUSIONS

EOS patients suffer substantial impairment from significant levels of positive and negative symptoms. Although symptoms and functioning improve significantly over time, pre-/and comorbid conditions are frequent, and longer DUP and poorer premorbid adjustment is associated with poorer illness outcome.

The impact of thought disorder on therapeutic alliance and personal recovery in schizophrenia and schizoaffective disorder: An exploratory study

Thought and language disorders are a main feature of schizophrenia. The aim of the study is to explore the impact of thought disorder on therapeutic alliance and personal recovery because of its interference with verbal communication. Thought disorder, positive and negative symptoms (Positive and Negative Syndrome Scale), functioning (Modified Global Assessment of Functioning scale), insight (Scale to Assess Unawareness of Mental Disorder), attachment insecurity (Psychosis Attachment Measure), therapeutic alliance (Scale to Assess the Therapeutic Relationship), and personal recovery (Recovery Assessment Scale, Integration Sealing-Over Scale) were assessed in 133 outpatients with schizophrenia or schizoaffective disorder at baseline and twelve months later. The data were analyzed by hierarchical multiple linear regression. Higher levels of thought disorder were significantly associated with lower clinicians' ratings, but not with patients' ratings of therapeutic alliance. In addition, lower clinicians' ratings of therapeutic alliance were significantly linked to a more sealing over and less integrative recovery style. In fact, the lower therapeutic alliance ratings mediated the association between thought disorder and a sealing over recovery style. The results highlight the importance of considering thought disorder in treatment of schizophrenia and schizoaffective disorder which may interfere with therapeutic alliance and treatment efforts towards recovery.

Executive impairment predicts schizophrenia diagnosis and treatment status in mid-term follow-up of early-onset psychosis

OBJECTIVES

Early-onset psychoses (EOP) vary considerably with regard to diagnostic stability and functional outcome. The aim of this study was the assessment of executive dysfunction as a predictor of outcome in EOP.

METHOD

This was a retrospective cohort study. Twenty-five hospitalized patients with non-affective EOP were assessed with the Wisconsin Card Sorting Test (WCST) during the index admission. Associations with current diagnosis, further admissions, current treatment status and occupational and relationship outcome were analyzed in 6 years of follow-up.

RESULTS

The mean age at the index admission and the follow-up was 16.1 ± 1.35 and 22.0 ± 2.1 years, respectively. After discharge, almost all subjects (96%) at least briefly continued psychiatric treatment, and the majority of them (76%) were readmitted. Worse baseline WCST results were associated with a follow-up schizophrenia diagnosis, being a psychiatric in- or outpatient at the moment of follow-up assessment and receiving psychotropic medication. A low number of completed categories correlated with receiving a disability pension at the follow-up.

CONCLUSION

In patients with EOP, baseline executive function impairment was associated with schizophrenia diagnosis and psychiatric treatment at the follow-up. The association between baseline results and psychiatric treatment may explain the limited effect of baseline impairment on follow-up occupational and relationship status.

Improvement of dizocilpine-induced social recognition deficits in mice by brexpiprazole, a novel serotonin-dopamine activity modulator

Cognitive impairment, including impaired social cognition, is largely responsible for the deterioration in social life suffered by patients with psychiatric disorders, such as schizophrenia and major depressive disorder (MDD). Brexpiprazole (7-{4-[4-(1-benzothiophen-4-yl)piperazin-1-yl]butoxy}quinolin-2(1H)-one), a novel serotonin-dopamine activity modulator, was developed to offer efficacious and tolerable therapy for different psychiatric disorders, including schizophrenia and adjunctive treatment of MDD. In this study, we investigated whether brexpiprazole could improve social recognition deficits (one of social cognition deficits) in mice, after administration of the N-methyl-d-aspartate (NMDA) receptor antagonist MK-801 (dizocilpine). Dosing with dizocilpine (0.1mg/kg) induced significant impairment of social recognition in mice. Brexpiprazole (0.01, 0.03, 0.1mg/kg, p.o.) significantly ameliorated dizocilpine-induced social recognition deficits, without sedation or a reduction of exploratory behavior. In addition, brexpiprazole alone had no effect on social recognition in untreated control mice. By contrast, neither risperidone (0.03mg/kg, p.o.) nor olanzapine (0.03mg/kg, p.o.) altered dizocilpine-induced social recognition deficits. Finally, the effect of brexpiprazole on dizocilpine-induced social recognition deficits was antagonized by WAY-100,635, a selective serotonin 5-HT1A antagonist. These results suggest that brexpiprazole could improve dizocilpine-induced social recognition deficits via 5-HT1A receptor activation in mice. Therefore, brexpiprazole may confer a beneficial effect on social cognition deficits in patients with psychiatric disorders.

Prevention and reversal of ketamine-induced schizophrenia related behavior by minocycline in mice: Possible involvement of antioxidant and nitrergic pathways

It has been hypothesized that oxidative imbalance and alterations in nitrergic signaling play a role in the neurobiology of schizophrenia. Preliminary evidence suggests that adjunctive minocycline treatment is efficacious for cognitive and negative symptoms of schizophrenia. This study investigated the effects of minocycline in the prevention and reversal of ketamine-induced schizophrenia-like behaviors in mice. In the reversal protocol, animals received ketamine (20 mg/kg per day intraperitoneally or saline for 14 days, and minocycline (25 or 50 mg/kg daily), risperidone or vehicle treatment from days 8 to 14. In the prevention protocol, mice were pretreated with minocycline, risperidone or vehicle prior to ketamine. Behaviors related to positive (locomotor activity and prepulse inhibition of startle), negative (social interaction) and cognitive (Y maze) symptoms of schizophrenia were also assessed. Glutathione (GSH), thiobarbituric acid-reactive substances (TBARS) and nitrite levels were measured in the prefrontal cortex, hippocampus and striatum. Minocycline and risperidone prevented and reversed ketamine-induced alterations in behavioral paradigms, oxidative markers (i.e. ketamine-induced decrease and increase in GSH levels and TBARS content, respectively) as well as nitrite levels in the striatum. These data provide a rationale for evaluating minocycline as a novel psychotropic agent and suggest that its mechanism of action includes antioxidant and nitrergic systems.