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1.
Mol Psychiatry ; 28(5): 2030-2038, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37095352

RESUMO

Studies applying Free Water Imaging have consistently reported significant global increases in extracellular free water (FW) in populations of individuals with early psychosis. However, these published studies focused on homogenous clinical participant groups (e.g., only first episode or chronic), thereby limiting our understanding of the time course of free water elevations across illness stages. Moreover, the relationship between FW and duration of illness has yet to be directly tested. Leveraging our multi-site diffusion magnetic resonance imaging(dMRI) harmonization approach, we analyzed dMRI scans collected by 12 international sites from 441 healthy controls and 434 individuals diagnosed with schizophrenia-spectrum disorders at different illness stages and ages (15-58 years). We characterized the pattern of age-related FW changes by assessing whole brain white matter in individuals with schizophrenia and healthy controls. In individuals with schizophrenia, average whole brain FW was higher than in controls across all ages, with the greatest FW values observed from 15 to 23 years (effect size range = [0.70-0.87]). Following this peak, FW exhibited a monotonic decrease until reaching a minima at the age of 39 years. After 39 years, an attenuated monotonic increase in FW was observed, but with markedly smaller effect sizes when compared to younger patients (effect size range = [0.32-0.43]). Importantly, FW was found to be negatively associated with duration of illness in schizophrenia (p = 0.006), independent of the effects of other clinical and demographic data. In summary, our study finds in a large, age-diverse sample that participants with schizophrenia with a shorter duration of illness showed higher FW values compared to participants with more prolonged illness. Our findings provide further evidence that elevations in the FW are present in individuals with schizophrenia, with the greatest differences in the FW being observed in those at the early stages of the disorder, which might suggest acute extracellular processes.

2.
Mol Psychiatry ; 27(9): 3719-3730, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35982257

RESUMO

Cognitive deficits are among the best predictors of real-world functioning in schizophrenia. However, our understanding of how cognitive deficits relate to neuropathology and clinical presentation over the disease lifespan is limited. Here, we combine multi-site, harmonized cognitive, imaging, demographic, and clinical data from over 900 individuals to characterize a) cognitive deficits across the schizophrenia lifespan and b) the association between cognitive deficits, clinical presentation, and white matter (WM) microstructure. Multimodal harmonization was accomplished using T-scores for cognitive data, previously reported standardization methods for demographic and clinical data, and an established harmonization method for imaging data. We applied t-tests and correlation analysis to describe cognitive deficits in individuals with schizophrenia. We then calculated whole-brain WM fractional anisotropy (FA) and utilized regression-mediation analyses to model the association between diagnosis, FA, and cognitive deficits. We observed pronounced cognitive deficits in individuals with schizophrenia (p < 0.006), associated with more positive symptoms and medication dosage. Regression-mediation analyses showed that WM microstructure mediated the association between schizophrenia and language/processing speed/working memory/non-verbal memory. In addition, processing speed mediated the influence of diagnosis and WM microstructure on the other cognitive domains. Our study highlights the critical role of cognitive deficits in schizophrenia. We further show that WM is crucial when trying to understand the role of cognitive deficits, given that it explains the association between schizophrenia and cognitive deficits (directly and via processing speed).


Assuntos
Transtornos Cognitivos , Esquizofrenia , Substância Branca , Humanos , Substância Branca/patologia , Esquizofrenia/patologia , Imagem de Tensor de Difusão , Transtornos Cognitivos/complicações , Anisotropia , Cognição , Encéfalo/patologia
3.
Mol Psychiatry ; 26(9): 5357-5370, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33483689

RESUMO

White matter (WM) abnormalities are repeatedly demonstrated across the schizophrenia time-course. However, our understanding of how demographic and clinical variables interact, influence, or are dependent on WM pathologies is limited. The most well-known barriers to progress are heterogeneous findings due to small sample sizes and the confounding influence of age on WM. The present study leverages access to the harmonized diffusion magnetic-resonance-imaging data and standardized clinical data from 13 international sites (597 schizophrenia patients (SCZ)). Fractional anisotropy (FA) values for all major WM structures in patients were predicted based on FA models estimated from a healthy population (n = 492). We utilized the deviations between predicted and real FA values to answer three essential questions. (1) "Which clinical variables explain WM abnormalities?". (2) "Does the degree of WM abnormalities predict symptom severity?". (3) "Does sex influence any of those relationships?". Regression and mediator analyses revealed that a longer duration-of-illness is associated with more severe WM abnormalities in several tracts. In addition, they demonstrated that a higher antipsychotic medication dose is related to more severe corpus callosum abnormalities. A structural equation model revealed that patients with more WM abnormalities display higher symptom severity. Last, the results exhibited sex-specificity. Males showed a stronger association between duration-of-illness and WM abnormalities. Females presented a stronger association between WM abnormalities and symptom severity, with IQ impacting this relationship. Our findings provide clear evidence for the interaction of demographic, clinical, and behavioral variables with WM pathology in SCZ. Our results also point to the need for longitudinal studies, directly investigating the casualty and sex-specificity of these relationships, as well as the impact of cognitive resiliency on structure-function relationships.


Assuntos
Esquizofrenia , Substância Branca , Anisotropia , Encéfalo/diagnóstico por imagem , Demografia , Imagem de Tensor de Difusão , Feminino , Humanos , Masculino , Substância Branca/diagnóstico por imagem
4.
Neuropsychobiology ; 81(4): 311-321, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35367989

RESUMO

INTRODUCTION: Deficits in social interaction and community functioning, including impaired use, performance, and perception of hand gestures, are key features in schizophrenia. A well-established tool to assess gesture deficits is the test of upper limb apraxia (TULIA). However, given its time-consuming application based on video analyses, research has proposed the bedside apraxia screen of TULIA (AST). This study aims to test the validity and reliability of the AST to detect gesture abnormalities at bedside in a sample of 27 patients diagnosed with schizophrenia, schizotypal disorder, acute and transient psychotic disorders, or schizoaffective disorder. METHODS: Patients completed the 48-item TULIA and the 12-item AST. Two different raters assessed the AST: one at bedside (online) and the other based on the video recordings. RESULTS: The total AST scores demonstrated a high parallel reliability, moderate inter-rater reliability on a single-item level, and good construct validities. CONCLUSIONS: The psychometric properties of the AST suggest it can well be used for the clinical assessment of gesture deficits in schizophrenia. However, when detailed information is required, the AST rated from video or conducting the full TULIA is recommended. The findings call for refining the selection of the TULIA items for a psychosis-AST bedside test to increase specificity.


Assuntos
Apraxias , Transtornos Psicóticos , Esquizofrenia , Apraxias/diagnóstico , Apraxias/etiologia , Gestos , Humanos , Transtornos Psicóticos/complicações , Transtornos Psicóticos/diagnóstico , Reprodutibilidade dos Testes , Esquizofrenia/complicações , Esquizofrenia/diagnóstico
5.
Eur Arch Psychiatry Clin Neurosci ; 272(6): 1021-1032, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34636951

RESUMO

Paranoia is a frequent and highly distressing experience in psychosis. Models of paranoia suggest limbic circuit pathology. Here, we tested whether resting-state functional connectivity (rs-fc) in the limbic circuit was altered in schizophrenia patients with current paranoia. We collected MRI scans in 165 subjects including 89 patients with schizophrenia spectrum disorders (schizophrenia, schizoaffective disorder, brief psychotic disorder, schizophreniform disorder) and 76 healthy controls. Paranoia was assessed using a Positive And Negative Syndrome Scale composite score. We tested rs-fc between bilateral nucleus accumbens, hippocampus, amygdala and orbitofrontal cortex between groups and as a function of paranoia severity. Patients with paranoia had increased connectivity between hippocampus and amygdala compared to patients without paranoia. Likewise, paranoia severity was linked to increased connectivity between hippocampus and amygdala. Furthermore, paranoia was associated with increased connectivity between orbitofrontal and medial prefrontal cortex. In addition, patients with paranoia had increased functional connectivity within the frontal hubs of the default mode network compared to healthy controls. These results demonstrate that current paranoia is linked to aberrant connectivity within the core limbic circuit and prefrontal cortex reflecting amplified threat processing and impaired emotion regulation. Future studies will need to explore the association between limbic hyperactivity, paranoid ideation and perceived stress.


Assuntos
Esquizofrenia , Tonsila do Cerebelo/fisiologia , Hipocampo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Vias Neurais/diagnóstico por imagem , Transtornos Paranoides/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Esquizofrenia/complicações , Esquizofrenia/diagnóstico por imagem
6.
Cereb Cortex ; 31(1): 201-212, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32851404

RESUMO

Axonal myelination and repair, critical processes for brain development, maturation, and aging, remain controlled by sexual hormones. Whether this influence is reflected in structural brain differences between sexes, and whether it can be quantified by neuroimaging, remains controversial. Diffusion-weighted magnetic resonance imaging (dMRI) is an in vivo method that can track myelination changes throughout the lifespan. We utilize a large, multisite sample of harmonized dMRI data (n = 551, age = 9-65 years, 46% females/54% males) to investigate the influence of sex on white matter (WM) structure. We model lifespan trajectories of WM using the most common dMRI measure fractional anisotropy (FA). Next, we examine the influence of both age and sex on FA variability. We estimate the overlap between male and female FA and test whether it is possible to label individual brains as male or female. Our results demonstrate regionally and spatially specific effects of sex. Sex differences are limited to limbic structures and young ages. Additionally, not only do sex differences diminish with age, but tracts within each subject become more similar to one another. Last, we show the high overlap in FA between sexes, which implies that determining sex based on WM remains open.


Assuntos
Caracteres Sexuais , Substância Branca/anatomia & histologia , Substância Branca/diagnóstico por imagem , Adolescente , Adulto , Idoso , Envelhecimento , Anisotropia , Axônios/fisiologia , Criança , Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Feminino , Humanos , Sistema Límbico/diagnóstico por imagem , Sistema Límbico/fisiologia , Masculino , Pessoa de Meia-Idade , Bainha de Mielina/fisiologia , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiologia , Adulto Jovem
7.
Compr Psychiatry ; 115: 152307, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35303585

RESUMO

BACKGROUND: Up to 50% of patients with schizophrenia are suffering from motor abnormalities, which may contribute to decreased quality of life, impaired work capacity, and a reduced life expectancy by 10-20 years. However, the effect of motor abnormalities on social and global functioning, as well as, functional capacity is not clear. We hypothesized, that the presence of motor abnormalities is associated with poorer functional outcomes in patients with schizophrenia. METHODS: We collected data on 5 different motor abnormalities in 156 patients suffering from schizophrenia spectrum disorders: parkinsonism, catatonia, dyskinesia, neurological soft signs and psychomotor slowing (PS). Additionally, we used three different scales to evaluate the functional outcomes in these patients: the Global Assessment of Functioning (GAF) and the Social and Occupational Functioning Assessment Scale (SOFAS) which use clinicians' judgment; and one using a performance-based measure of functional capacity, the brief version of the UCSD Performance-based Skills Assessment (UPSA-B). RESULTS: Our analysis demonstrated that patients with catatonia (all F > 4.5; p < 0.035) and parkinsonism (all F > 4.9; p < 0.027) scored lower on GAF and SOFAS compared to patients without catatonia and parkinsonism. In contrast, no significant difference on functional outcomes between patients with dyskinesia versus without dyskinesia exist in our study. Furthermore, there are statistically significant negative correlations for parkinsonism and PS with GAF, SOFAS and UPSA-B (all tau are at least -0.152, p-value <0.036). We also found significant negative correlations between catatonia and both GAF & SOFAS (all tau are at least -0.203, p-value<0.001) and between NES and SOFAS (tau = -0.137, p-value = 0.033). CONCLUSION: Here, we showed that four of the most common motor abnormalities observed in schizophrenia were associated with at least one of the patients' functional outcomes. The stronger the motor impairment was the worse the global and social functioning. Future studies need to test, whether amelioration of motor abnormalities is linked to improved community functioning.


Assuntos
Catatonia , Discinesias , Esquizofrenia , Catatonia/diagnóstico , Discinesias/diagnóstico , Humanos , Qualidade de Vida , Esquizofrenia/complicações , Esquizofrenia/diagnóstico
8.
Hum Brain Mapp ; 42(14): 4658-4670, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34322947

RESUMO

Diffusion MRI studies consistently report group differences in white matter between individuals diagnosed with schizophrenia and healthy controls. Nevertheless, the abnormalities found at the group-level are often not observed at the individual level. Among the different approaches aiming to study white matter abnormalities at the subject level, normative modeling analysis takes a step towards subject-level predictions by identifying affected brain locations in individual subjects based on extreme deviations from a normative range. Here, we leveraged a large harmonized diffusion MRI dataset from 512 healthy controls and 601 individuals diagnosed with schizophrenia, to study whether normative modeling can improve subject-level predictions from a binary classifier. To this aim, individual deviations from a normative model of standard (fractional anisotropy) and advanced (free-water) dMRI measures, were calculated by means of age and sex-adjusted z-scores relative to control data, in 18 white matter regions. Even though larger effect sizes are found when testing for group differences in z-scores than are found with raw values (p < .001), predictions based on summary z-score measures achieved low predictive power (AUC < 0.63). Instead, we find that combining information from the different white matter tracts, while using multiple imaging measures simultaneously, improves prediction performance (the best predictor achieved AUC = 0.726). Our findings suggest that extreme deviations from a normative model are not optimal features for prediction. However, including the complete distribution of deviations across multiple imaging measures improves prediction, and could aid in subject-level classification.


Assuntos
Imagem de Tensor de Difusão/normas , Aprendizado de Máquina , Esquizofrenia/classificação , Esquizofrenia/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Medicina de Precisão , Valor Preditivo dos Testes , Esquizofrenia/patologia , Substância Branca/patologia , Adulto Jovem
9.
Mol Psychiatry ; 25(12): 3208-3219, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-31511636

RESUMO

Several prominent theories of schizophrenia suggest that structural white matter pathologies may follow a developmental, maturational, and/or degenerative process. However, a lack of lifespan studies has precluded verification of these theories. Here, we analyze the largest sample of carefully harmonized diffusion MRI data to comprehensively characterize age-related white matter trajectories, as measured by fractional anisotropy (FA), across the course of schizophrenia. Our analysis comprises diffusion scans of 600 schizophrenia patients and 492 healthy controls at different illness stages and ages (14-65 years), which were gathered from 13 sites. We determined the pattern of age-related FA changes by cross-sectionally assessing the timing of the structural neuropathology associated with schizophrenia. Quadratic curves were used to model between-group FA differences across whole-brain white matter and fiber tracts at each age; fiber tracts were then clustered according to both the effect-sizes and pattern of lifespan white matter FA differences. In whole-brain white matter, FA was significantly lower across the lifespan (up to 7%; p < 0.0033) and reached peak maturation younger in patients (27 years) compared to controls (33 years). Additionally, three distinct patterns of neuropathology emerged when investigating white matter fiber tracts in patients: (1) developmental abnormalities in limbic fibers, (2) accelerated aging and abnormal maturation in long-range association fibers, (3) severe developmental abnormalities and accelerated aging in callosal fibers. Our findings strongly suggest that white matter in schizophrenia is affected across entire stages of the disease. Perhaps most strikingly, we show that white matter changes in schizophrenia involve dynamic interactions between neuropathological processes in a tract-specific manner.


Assuntos
Esquizofrenia , Substância Branca , Adolescente , Adulto , Idoso , Anisotropia , Encéfalo/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Humanos , Longevidade , Pessoa de Meia-Idade , Esquizofrenia/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto Jovem
10.
Hum Brain Mapp ; 39(9): 3691-3700, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29722099

RESUMO

Parkinson's disease (PD) patients frequently suffer from limb kinetic apraxia (LKA) affecting quality of life. LKA denotes an impairment of precise and independent finger movements beyond bradykinesia, which is reliably assessed by coin rotation (CR) task. BOLD fMRI detected activation of a left inferior parietal-premotor praxis network in PD during CR. Here, we explored which network site is most critical for LKA using arterial spin labeling (ASL). Based on a hierarchical model, we hypothesized that LKA would predominantly affect the functional integrity of premotor areas including supplementary motor areas (SMA). Furthermore, we suspected that for praxis function with higher demand on temporal-spatial processing such as gesturing, inferior parietal lobule (IPL) upstream to premotor areas would be essential. A total of 21 PD patients and 20 healthy controls underwent ASL acquisition during rest. Behavioral assessment outside the scanner involved the CR, finger tapping task, and the test of upper limb apraxia (TULIA). Whole-brain analysis of activity at rest showed a significant reduction of CR-related perfusion in the left SMA of PD. Furthermore, the positive correlation between SMA perfusion and CR, seen in controls, was lost in patients. By contrast, TULIA was significantly associated with the perfusion of left IPL in both patients and controls. In conclusion, the findings suggest that LKA in PD are linked to an intrinsic disruption of the left SMA function, which may only be overcome by compensatory network activation. In addition, gestural performance relies on IPL which remains available for functional recruitment in early PD.


Assuntos
Apraxia Ideomotora/etiologia , Imageamento por Ressonância Magnética , Córtex Motor/patologia , Neuroimagem , Doença de Parkinson/patologia , Idoso , Apraxia Ideomotora/diagnóstico por imagem , Apraxia Ideomotora/patologia , Apraxia Ideomotora/fisiopatologia , Feminino , Dedos/fisiopatologia , Gestos , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Motor/fisiopatologia , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/fisiopatologia , Desempenho Psicomotor/fisiologia , Descanso , Marcadores de Spin
11.
Eur Arch Psychiatry Clin Neurosci ; 268(1): 99-104, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28032254

RESUMO

Disorganized speech is related to functional abnormalities in schizophrenia. To test the association between formal thought disorders (FTDs) and white matter microstructure, we applied a behavioral rating and diffusion tensor imaging in 61 patients with schizophrenia spectrum disorders. The Bern Psychopathology Scale was used to rate the dimension of language abnormalities ranging from negative FTDs, basically unaltered speech, to positive FTDs. Tract-based spatial statistics indicated increased fractional anisotropy in left hemispheric pathways of the language system in patients with negative FTDs. Thus, altered white matter properties in relevant fiber tracts may represent vulnerability to specific formal thought disorders.


Assuntos
Esquizofrenia/complicações , Distúrbios da Fala/etiologia , Estatística como Assunto , Substância Branca/patologia , Adulto , Análise de Variância , Anisotropia , Imagem de Tensor de Difusão , Feminino , Lateralidade Funcional , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Distúrbios da Fala/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
12.
Pharmacopsychiatry ; 51(6): 257-262, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29390199

RESUMO

INTRODUCTION: Substantial evidence has indicated an association between hypogonadism and depressive symptoms, which led to the conduction of studies that found an ameliorating effect of testosterone (T) supplementation (S) upon depression in men. METHODS: Retrospective analysis of medical records identified 16 depressed, hypogonadal men who have not responded adequately to initial antidepressant therapy and subsequently received intramuscular T injections. Following the proposal of Button et al., a minimal clinically important difference was defined as an 18% reduction of the Beck Depression Inventory-II (BDI-II) score. RESULTS: After TS, the BDI-II score decreased by approximately 31% (p<0.01), from 27.2 (mean; standard deviation [SD] 11.8) to 18.8 (mean; SD 11.3). Patients with baseline BDI-II scores ranging from 29 to 63 (severe depression) showed a significantly higher absolute and relative reduction through TS. Also, men with a shorter depression duration (<2 years) demonstrated a greater benefit. CONCLUSIONS: The depressed, hypogonadal men generally benefited from TS given that the BDI-II score reduction was almost twice as much as needed for a minimal clinically important difference.


Assuntos
Antidepressivos/administração & dosagem , Depressão/tratamento farmacológico , Depressão/etiologia , Hipogonadismo/complicações , Testosterona/administração & dosagem , Adulto , Humanos , Injeções Intramusculares/métodos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Escalas de Graduação Psiquiátrica , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
13.
Ther Umsch ; 75(1): 31-36, 2018 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-29909765

RESUMO

Diagnosis and treatment of motor phenomena in schizophrenia spectrum disorders Abstract. Motor abnormalities are intrinsic features of schizophrenia spectrum disorders. They may be spontaneous or antipsychotic drug-induced. The four most important symptom groups are abnormal involuntary movements or dyskinesia, Parkinsonism, catatonia and neurological soft signs. In addition, there are further motor abnormalities, which are less frequent and less operationalized. The suspected etiology of motor abnormalities is strongly associated with altered neurodevelopment. Delayed maturation in conjunction with environmental insults may give further rise to motor symptoms. For the four most relevant motor abnormalities clinical examination procedures and rating scales are available, aiding clinicians in both screening and evaluation of symptom severity. Besides these currently instrumental measures are being tested for wide spread and easy application. Treatment of motor abnormalities is necessary according to subjective well-being. Treatment options are few and remain symptomatic. The most important strategy is critical evaluation of antispychotic pharmacotherapy. Benefitial effects on motor phenomena have been noted with clozapine. Currently, specific substances against tardive dyskinesia and non-invasive brain stimulation techniques are being evaluated. However, the effeciacy of these approaches will only be available in the near future.


Assuntos
Transtornos Motores/terapia , Esquizofrenia/terapia , Psicologia do Esquizofrênico , Adulto , Antipsicóticos/efeitos adversos , Antipsicóticos/uso terapêutico , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Criança , Terapia Combinada , Discinesia Induzida por Medicamentos/diagnóstico , Discinesia Induzida por Medicamentos/fisiopatologia , Discinesia Induzida por Medicamentos/terapia , Humanos , Transtornos Motores/diagnóstico , Transtornos Motores/fisiopatologia , Exame Neurológico , Sintomas Prodrômicos , Prognóstico , Fatores de Risco , Esquizofrenia/diagnóstico , Esquizofrenia/fisiopatologia
14.
Neuropsychobiology ; 75(3): 100-116, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29258073

RESUMO

Schizophrenia research has been in a deadlock for many decades. Despite important advances in clinical treatment, there are still major concerns regarding long-term psychosocial reintegration and disease management, biological heterogeneity, unsatisfactory predictors of individual course and treatment strategies, and a confusing variety of controversial theories about its etiology and pathophysiological mechanisms. In the present perspective on schizophrenia research, we first discuss a methodological pitfall in contemporary schizophrenia research inherent in the attempt to link mental phenomena with the brain: we claim that the time-honored phenomenological method of defining mental symptoms should not be contaminated with the naturalistic approach of modern neuroscience. We then describe our Systems Neuroscience of Psychosis (SyNoPsis) project, which aims to overcome this intrinsic problem of psychiatric research. Considering schizophrenia primarily as a disorder of interindividual communication, we developed a neurobiologically informed semiotics of psychotic disorders, as well as an operational clinical rating scale. The novel psychopathology allows disentangling the clinical manifestations of schizophrenia into behavioral domains matching the functions of three well-described higher-order corticobasal brain systems involved in interindividual human communication, namely, the limbic, associative, and motor loops, including their corticocortical sensorimotor connections. The results of several empirical studies support the hypothesis that the proposed three-dimensional symptom structure, segregated into the affective, the language, and the motor domain, can be specifically mapped onto structural and functional abnormalities of the respective brain systems. New pathophysiological hypotheses derived from this brain system-oriented approach have helped to develop and improve novel treatment strategies with noninvasive brain stimulation and practicable clinical parameters. In clinical practice, the novel psychopathology allows confining the communication deficits of the individual patient, shifting attention from the symptoms to the intact resources. We have studied this approach and observed important advantages for therapeutic alliances, personalized treatment, and de-escalation strategies. Future studies will further conjoin clinical definitions of psychotic symptoms with brain structures and functions, and disentangle structural and functional deficit patterns within these systems to identify neurobiologically distinct subsyndromes. Neurobiologically homogeneous patient groups may provide new momentum for treatment research. Finally, lessons learned from schizophrenia research may contribute to developing a comprehensive perspective on human experience and behavior that integrates methodologically distinct, but internally consistent, insights from humanities and neuroscience.


Assuntos
Encéfalo/fisiopatologia , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Animais , Humanos , Modelos Neurológicos , Vias Neurais , Neurociências , Projetos de Pesquisa
15.
J Neural Transm (Vienna) ; 123(12): 1387-1393, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27619658

RESUMO

Dorsal pre-motor cortex (PMd) is thought to play a role in fine motor control. The aim of the present study was to investigate whether inhibitory or excitatory stimulation of PMd would have an impact on manual dexterity in Parkinson's disease (PD). Fifteen patients with PD participated in this study. High resolution structural MRI was used for neuro-navigated TBS. Participants were targeted with one train of TBS in three experimental sessions: sham stimulation over vertex, continuous TBS (cTBS) over PMd and intermittent TBS (iTBS) over PMd, respectively. Dexterity was measured by a coin rotation task (CRT), which is a valid measure to detect limb kinetic apraxia (LKA). Neither cTBS or iTBS significantly interfered with CRT. Post hoc sub-analysis in a group of PD patients (n = 5) with stronger baseline impairment, indicating LKA, revealed further deterioration of dexterous performance for the cTBS condition (p = 0.04). This sham controlled pilot study demonstrates that TBS over PMd does not significantly interfere with dexterity in PD. However, patients with dexterous impairment qualifying for LKA may be more susceptible to TBS.


Assuntos
Lateralidade Funcional/fisiologia , Córtex Motor/fisiologia , Doença de Parkinson/terapia , Desempenho Psicomotor/fisiologia , Ritmo Teta/fisiologia , Estimulação Magnética Transcraniana/métodos , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Potencial Evocado Motor/fisiologia , Feminino , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Motor/diagnóstico por imagem , Doença de Parkinson/fisiopatologia
16.
Neuropsychobiology ; 73(4): 201-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27229523

RESUMO

BACKGROUND/AIM: Gesturing plays an important role in social behavior and social learning. Deficits are frequent in schizophrenia and may contribute to impaired social functioning. Information about deficits during the course of the disease and presence of severity and patterns of impairment in first-episode patients is missing. Hence, we aimed to investigate gesturing in first- compared to multiple-episode schizophrenia patients and healthy controls. METHODS: In 14 first-episode patients, 14 multiple-episode patients and 16 healthy controls matched for age, gender and education, gesturing was assessed by the comprehensive Test of Upper Limb Apraxia. Performance in two domains of gesturing - imitation and pantomime - was recorded on video. Raters of gesture performance were blinded. RESULTS: Patients with multiple episodes had severe gestural deficits. For almost all gesture categories, performance was worse in multiple- than in first-episode patients. First-episode patients demonstrated subtle deficits with a comparable pattern. CONCLUSIONS: Subjects with multiple psychotic episodes have severe deficits in gesturing, while only mild impairments were found in first-episode patients independent of age, gender, education and negative symptoms. The results indicate that gesturing is impaired at the onset of disease and likely to further deteriorate during its course.


Assuntos
Gestos , Comportamento Imitativo , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Aprendizado Social , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Comunicação não Verbal/psicologia , Índice de Gravidade de Doença , Gravação em Vídeo , Adulto Jovem
17.
Eur Arch Psychiatry Clin Neurosci ; 265(4): 303-11, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25119145

RESUMO

Patients suffering from bipolar affective disorder show deficits in working memory functions. In a previous functional magnetic resonance imaging study, we observed an abnormal hyperactivity of the amygdala in bipolar patients during articulatory rehearsal in verbal working memory. In the present study, we investigated the dynamic neurofunctional interactions between the right amygdala and the brain systems that underlie verbal working memory in both bipolar patients and healthy controls. In total, 18 euthymic bipolar patients and 18 healthy controls performed a modified version of the Sternberg item-recognition (working memory) task. We used the psychophysiological interaction approach in order to assess functional connectivity between the right amygdala and the brain regions involved in verbal working memory. In healthy subjects, we found significant negative functional interactions between the right amygdala and multiple cortical brain areas involved in verbal working memory. In comparison with the healthy control subjects, bipolar patients exhibited significantly reduced functional interactions of the right amygdala particularly with the right-hemispheric, i.e., ipsilateral, cortical regions supporting verbal working memory. Together with our previous finding of amygdala hyperactivity in bipolar patients during verbal rehearsal, the present results suggest that a disturbed right-hemispheric "cognitive-emotional" interaction between the amygdala and cortical brain regions underlying working memory may be responsible for amygdala hyperactivation and affects verbal working memory (deficits) in bipolar patients.


Assuntos
Tonsila do Cerebelo/patologia , Transtorno Bipolar/complicações , Transtorno Bipolar/patologia , Córtex Cerebral/patologia , Transtornos da Memória/etiologia , Memória de Curto Prazo/fisiologia , Vias Neurais/fisiopatologia , Adulto , Tonsila do Cerebelo/irrigação sanguínea , Análise de Variância , Córtex Cerebral/irrigação sanguínea , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Vias Neurais/irrigação sanguínea , Oxigênio/sangue , Estimulação Luminosa , Escalas de Graduação Psiquiátrica , Psicofísica , Aprendizagem Verbal , Adulto Jovem
18.
Schizophrenia (Heidelb) ; 9(1): 51, 2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37573445

RESUMO

Negative symptoms (NS) are a core component of schizophrenia affecting community functioning and quality of life. We tested neural correlates of NS considering NS factors and consensus subdomains. We assessed NS using the Clinical Assessment Interview for Negative Symptoms and the Scale for Assessment of Negative Symptoms. Arterial spin labeling was applied to measure resting-state cerebral blood flow (rCBF) in 47 schizophrenia patients and 44 healthy controls. Multiple regression analyses calculated the relationship between rCBF and NS severity. We found an association between diminished expression (DE) and brain perfusion within the cerebellar anterior lobe and vermis, and the pre-, and supplementary motor area. Blunted affect was linked to fusiform gyrus and alogia to fronto-striatal rCBF. In contrast, motivation and pleasure was not associated with rCBF. These results highlight the key role of motor areas for DE. Considering NS factors and consensus subdomains may help identifying specific pathophysiological pathways of NS.

19.
Neuroimage Clin ; 40: 103527, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37871539

RESUMO

Auditory Verbal Hallucinations (AVH) are highly prevalent in patients with schizophrenia. AVH with high emotional content lead to particularly poor functional outcome. Increasing evidence shows that AVH are associated with alterations in structure and function in language and memory related brain regions. However, neural correlates of AVH with emotional content remain unclear. In our study (n = 91), we related resting-state cerebral perfusion to AVH and emotional content, comparing four groups: patients with AVH with emotional content (n = 13), without emotional content (n = 14), without hallucinations (n = 20) and healthy controls (n = 44). Patients with AVH and emotional content presented with increased perfusion within the amygdala and the ventromedial and dorsomedial prefrontal cortex (vmPFC/ dmPFC) compared to patients with AVH without emotional content. In addition, patients with any AVH showed hyperperfusion within the anterior cingulate gyrus, the vmPFC/dmPFC, the right hippocampus, and the left pre- and postcentral gyrus compared to patients without AVH. Our results indicate metabolic alterations in brain areas critical for the processing of emotions as key for the pathophysiology of AVH with emotional content. Particularly, hyperperfusion of the amygdala may reflect and even trigger emotional content of AVH, while hyperperfusion of the vmPFC/dmPFC cluster may indicate insufficient top-down amygdala regulation in patients with schizophrenia.


Assuntos
Esquizofrenia , Humanos , Esquizofrenia/complicações , Esquizofrenia/diagnóstico por imagem , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Alucinações/diagnóstico por imagem , Alucinações/etiologia , Emoções , Perfusão
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