Mabel Rodriguez

Differences in onset of disease and severity of psychopathology between toxoplasmosis-related and toxoplasmosis-unrelated schizophrenia.

Toxoplasmosis is a lifelong parasitic disease that appears to be associated to schizophrenia. However, no distinguishing attributes in Toxoplasma‐infected schizophrenia patients have been described as yet.

The Application of Vagus Nerve Stimulation and Deep Brain Stimulation in Depression

Despite the progress in the pharmacotherapy of depression, there is a substantial proportion of treatment-resistant patients. Recently, reversible invasive stimulation methods, i.e. vagus nerve stimulation (VNS) and deep brain stimulation (DBS), have been introduced into the management of treatment-resistant depression (TRD). VNS has already received regulatory approval for TRD. This paper reviews the available clinical evidence and neurobiology of VNS and DBS in TRD. The principle of VNS is a stimulation of the left cervical vagus nerve with a programmable neurostimulator. VNS was examined in 4 clinical trials with 355 patients. VNS demonstrated steadily increasing improvement with full benefit after 6–12 months, sustained up to 2 years. Patients who responded best had a low-to-moderate antidepressant resistance. However, the primary results of the only controlled trial were negative. DBS involves stereotactical implantation of electrodes powered by a pulse generator into the specific brain regions. For depression, the targeted areas are the subthalamic nucleus, internal globus pallidus, ventral internal capsule/ventral striatum, the subgenual cingulated region, and the nucleus accumbens. Antidepressant effects of DBS were examined in case series with a total number of 50 TRD patients. Stimulation of different brain regions resulted in a reduction of depressive symptoms. The clinical data on the use of VNS and DBS in TRD are encouraging. The major contribution of the methods is a novel approach that allows for precise targeting of the specific brain areas, nuclei and circuits implicated in the etiopathogenesis of neuropsychiatric disorders. For clinical practice, it is necessary to identify patients who may best benefit from VNS or DBS.

A virtual reality task based on animal research – spatial learning and memory in patients after the first episode of schizophrenia

Objectives: Cognitive deficit is considered to be a characteristic feature of schizophrenia disorder. A similar cognitive dysfunction was demonstrated in animal models of schizophrenia. However, the poor comparability of methods used to assess cognition in animals and humans could be responsible for low predictive validity of current animal models. In order to assess spatial abilities in schizophrenia and compare our results with the data obtained in animal models, we designed a virtual analog of the Morris water maze (MWM), the virtual Four Goals Navigation (vFGN) task. Methods: Twenty-nine patients after the first psychotic episode with schizophrenia symptoms and a matched group of healthy volunteers performed the vFGN task. They were required to find and remember four hidden goal positions in an enclosed virtual arena. The task consisted of two parts. The Reference memory (RM) session with a stable goal position was designed to test spatial learning. The Delayed-matching-to-place (DMP) session presented a modified working memory protocol designed to test the ability to remember a sequence of three hidden goal positions. Results: Data obtained in the RM session show impaired spatial learning in schizophrenia patients compared to the healthy controls in pointing and navigation accuracy. The DMP session showed impaired spatial memory in schizophrenia during the recall of spatial sequence and a similar deficit in spatial bias in the probe trials. The pointing accuracy and the quadrant preference showed higher sensitivity toward the cognitive deficit than the navigation accuracy. Direct navigation to the goal was affected by sex and age of the tested subjects. The age affected spatial performance only in healthy controls. Conclusions: Despite some limitations of the study, our results correspond well with the previous studies in animal models of schizophrenia and support the decline of spatial cognition in schizophrenia, indicating the usefulness of the vFGN task in comparative research.

Comparison of Visuospatial and Verbal Abilities in First Psychotic Episode of Schizophrenia Spectrum Disorder: Impact on Global Functioning and Quality of Life

Objectives: Deficit in visuospatial functions can influence both simple and complex daily life activities. Despite the fact that visuospatial deficit was reported in schizophrenia, research on visuospatial functions as an independent entity is limited. Our study aims to elucidate the impact of visuospatial deficit in comparison with verbal deficit on global functioning and quality of life in the first psychotic episode of schizophrenia spectrum disorder (FES). The significance of clinical symptoms and antipsychotic medication was also studied. Methods: Thirty-six FES patients and a matched group of healthy controls (HC group) were assessed with a neuropsychological battery focused on visuospatial (VIS) and verbal (VERB) functions. Using multiple regression analysis, we evaluated the cumulative effect of VERB and VIS functions, psychiatric symptoms (PANSS) and antipsychotic medication on global functioning (GAF) and quality of life (WHOQOL-BREF) in the FES group. Results: The FES group demonstrated significant impairment both in VIS and VERB cognitive abilities compared to the HC group. Antipsychotic medication did not significantly affect either VIS or VERB functioning. PANSS was not related to cognitive functioning, apart from the Trail Making Test B. In the FES group, the GAF score was significantly affected by the severity of positive symptoms and VERB functioning, explaining together 60% of GAF variability. The severity of negative and positive symptoms affected only the Physical health domain of WHOQOL-BREF. The degree of VERB deficit was associated with both Physical and Psychological health. Although we did not find any relation between VIS functioning, GAF, and WHOQOL-BREF, a paradoxical finding emerged in the Environment quality domain, where a worse quality of the environment was associated with better VIS functioning. Conclusions: Our results suggest that the deficit in VIS functions is an integral part of cognitive deficit in schizophrenia spectrum disorders, rather than a side effect of symptomatology or antipsychotic medication. Moreover, VERB functioning was a better predictor of GAF and WHOQOL-BREF than VIS functioning. Given the findings of negative or missing effect of VIS deficit on WHOQOL-BREF and GAF, the accuracy of these measures in evaluating the impact of global cognitive deficit on everyday life in schizophrenia could be questioned.

Social and functional capacity of schizophrenia patients: A cross-sectional study

Background: The chronic course of schizophrenia typically results in severe social, vocational and functional impairment, interferes with patients’ autonomy, reduces quality of life and increases disability. Aims: The aim of our study was: (1) to assess social and functional impairment in schizophrenia outpatients from the Czech Republic and Slovakia; and (2) to examine a relationship between functioning and antipsychotic treatment and demographic variables. Methods: Schizophrenia outpatients in a stable phase of illness, treated with current antipsychotic medication for a minimum of one month, were enrolled for the study. Demographic and medication data were recorded. The Personal and Social Performance (PSP), Subjective Well-Being under Neuroleptics (SWN) and Clinical Global Impressions (CGI) scales were administered. Results: The total number of study subjects was 926. Most PSP values were within the interval of moderate impairment. Functional performance correlated positively with subjective satisfaction with medication and negatively with symptom severity. Higher education predicted better functioning on PSP. The best performance was associated with a stable relationship and a useful work role. Patients who showed the best level of functioning were more likely to be treated with antipsychotic monotherapy. No difference among drugs in monotherapy was found in subjective satisfaction. Conclusions: The PSP values of stable schizophrenia outpatients indicated a moderate degree of impairment. Improvement of functional capacity remains one of the unmet needs of schizophrenia patients.

Theoretical modelling of cognitive dysfunction in schizophrenia by means of errors and corresponding brain networks

The current evidence of cognitive disturbances and brain alterations in schizophrenia does not provide the plausible explanation of the underlying mechanisms. Neuropsychological studies outlined the cognitive profile of patients with schizophrenia, that embodied the substantial disturbances in perceptual and motor processes, spatial functions, verbal and non-verbal memory, processing speed and executive functioning. Standardized scoring in the majority of the neurocognitive tests renders the index scores or the achievement indicating the severity of the cognitive impairment rather than the actual performance by means of errors. At the same time, the quantitative evaluation may lead to the situation when two patients with the same index score of the particular cognitive test, demonstrate qualitatively different performances. This may support the view why test paradigms that habitually incorporate different cognitive variables associate weakly, reflecting an ambiguity in the interpretation of noted cognitive constructs. With minor exceptions, cognitive functions are not attributed to the localized activity but eventuate from the coordinated activity in the generally dispersed brain networks. Functional neuroimaging has progressively explored the connectivity in the brain networks in the absence of the specific task and during the task processing. The spatio-temporal fluctuations of the activity of the brain areas detected in the resting state and being highly reproducible in numerous studies, resemble the activation and communication patterns during the task performance. Relatedly, the activation in the specific brain regions oftentimes is attributed to a number of cognitive processes. Given the complex organization of the cognitive functions, it becomes crucial to designate the roles of the brain networks in relation to the specific cognitive functions. One possible approach is to identify the commonalities of the deficits across the number of cognitive tests or, common errors in the various tests and identify their common “denominators” in the brain networks. The qualitative characterization of cognitive performance might be beneficial in addressing diffuse cognitive alterations presumably caused by the dysconnectivity of the distributed brain networks. Therefore, in the review, we use this approach in the description of standardized tests in the scope of potential errors in patients with schizophrenia with a subsequent reference to the brain networks.

Case report: Is verbal cognitive performance in bilingual neuropsychiatric patients test-language dependent?

Bilingualism (BL) is increasing around the world. Although BL has been shown to have a broad impact-both positive and negative-on language and cognitive functioning, cognitive models and standards are mainly based on monolinguals. If we take cognitive performance of monolinguals as a standard, then the performance of bilinguals might not be accurately estimated. The assessment of cognitive functions is an important part of both the diagnostic process and further treatment in neurological and neuropsychiatric patients. In order to identify the presence or absence of cognitive deficit in bilingual patients, it will be important to determine the positive and/or negative impact of BL properties on measured cognitive performance. However, research of the impact of BL on cognitive performance in neuropsychiatric patients is limited. This article aims to compare the influence of the language (dominant-L1, second-L2) used for assessment of verbal cognitive performance in two cases of bilingual neuropsychiatric patients (English/Czech). Despite the fact that the two cases have different diagnoses, similarities in working memory and verbal learning profiles for L1 and L2 were present in both patients. We expected L1 to have higher performance in all measures when compared with L2. This assumption was partially confirmed. As expected, verbal working memory performance was better when assessed in L1. In contrast, verbal learning showed the same or better performance in L2 when compared with L1. Verbal fluency and immediate recall results were comparable in both languages. In conclusion, the language of administration partially influenced verbal performance of bilingual patients. Whether the language itself influenced low performance in a given language or it was a result of a deficit requires further research. According to our results, we suggest that an assessment in both languages needs to be a component of reasonable cognitive assessment of bilingual patients.

Spatial memory in a virtual arena: Human virtual analogue of the Morris water maze

The assessment of cognitive functions represents a crucial step in the diagnostics and therapy of mental disorders such as schizophrenia. To assess spatial learning, mental flexibility and working memory using a test applicable in clinical research, we designed virtual analogue of the spatial animal task: the Morris water maze (MWM). The task of the tested subject was simply to find and remember several hidden goal positions placed in an enclosed circular arena. Data obtained in 30 schizophrenia patients show cognitive deficit in the newly-developed virtual task in comparison to healthy volunteers, indicating its possible application as a tool for diagnostics or remediation of cognitive functions.

2696 – Functional capacity and subjective satisfaction with medication in schizophrenia patients

Objective The aim of our cross-sectional study was (1) to assess social and functional impairment in schizophrenia outpatients from the Czech and Slovak Republics, and (2) to examine a relationship between functional impairment and antipsychotic treatment and demographic variables. Method Enrolled were schizophrenia outpatients in a stable phase of illness, treated with current antipsychotic medication for a minimum of one month. Recorded were demographic and medication data, administered were Personal and Social Performance Scale (PSP), Subjective Well-being Under Neuroleptics (SWN), and CGI scale. Results The total number of study subjects was 926. Most PSP values were within the interval of moderate impairment. Functional performance correlated positively with subjective satisfaction with medication and negatively with symptom severity. Higher education predicted better functioning on PSP. The best performance was associated with a stable relationship and a useful work role. The patients who showed the best level of functioning were more likely to be treated with antipsychotic monotherapy. No difference among drugs in monotherapy was found in subjective satisfaction. Conclusion The PSP values of stable schizophrenia outpatients indicated moderate degree of impairment. Improvement of functional capacity remains one of the unmet needs of schizophrenia patients.