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1.
Hum Brain Mapp ; 44(6): 2465-2478, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36744628

RESUMO

The choroid plexus (ChP) is part of the blood-cerebrospinal fluid barrier, regulating brain homeostasis and the brain's response to peripheral events. Its upregulation and enlargement are considered essential in psychosis. However, the timing of the ChP enlargement has not been established. This study introduces a novel magnetic resonance imaging-based segmentation method to examine ChP volumes in two cohorts of individuals with psychosis. The first sample consists of 41 individuals with early course psychosis (mean duration of illness = 1.78 years) and 30 healthy individuals. The second sample consists of 30 individuals with chronic psychosis (mean duration of illness = 7.96 years) and 34 healthy individuals. We utilized manual segmentation to measure ChP volumes. We applied ANCOVAs to compare normalized ChP volumes between groups and partial correlations to investigate the relationship between ChP, LV volumes, and clinical characteristics. Our segmentation demonstrated good reliability (.87). We further showed a significant ChP volume increase in early psychosis (left: p < .00010, right: p < .00010) and a significant positive correlation between higher ChP and higher LV volumes in chronic psychosis (left: r = .54, p = .0030, right: r = .68; p < .0010). Our study suggests that ChP enlargement may be a marker of acute response around disease onset. It might also play a modulatory role in the chronic enlargement of lateral ventricles, often reported in psychosis. Future longitudinal studies should investigate the dynamics of ChP enlargement as a promising marker for novel therapeutic strategies.


Assuntos
Plexo Corióideo , Transtornos Psicóticos , Humanos , Plexo Corióideo/diagnóstico por imagem , Plexo Corióideo/patologia , Reprodutibilidade dos Testes , Transtornos Psicóticos/diagnóstico por imagem , Transtornos Psicóticos/patologia , Imageamento por Ressonância Magnética , Encéfalo/patologia
2.
Int J Psychiatry Clin Pract ; 26(2): 213-216, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34375167

RESUMO

OBJECTIVE: Patients with schizophrenia are at higher risk of cardiovascular (CVS) related mortality. Close attention is being paid to the clinical utility of readily available CVS markers. METHODS: A pilot one-year longitudinal study in inpatients with first-episode psychosis (FEP) was carried out to determine markers of inflammation and endothelial dysfunction (monocyte- and neutrophil-to-lymphocyte ratios) and basal blood pressure, pulse, and derived hemodynamic parameters (PP: pulse pressure; RPP: rate pressure product; and MAP: mean arterial pressure). RESULTS: After one year, PP and RPP increased, as did systolic blood pressure and heart rate. Systolic blood pressure, PP, total white blood cells, and neutrophils correlated with weight gain. After one year, correlations between monocyte-to-lymphocyte ratio and RPP and MAP were observed. CONCLUSION: Our study indicates worsening CVS health over the first year of treatment and emphasises the importance of early monitoring of CVS status using easily accessible parameters to prevent CVS-related mortality.Key pointsPatients with schizophrenia are at higher risk of cardiovascular mortality.The CVS risk could be evaluated using affordable, routinely available CVS markers such as monocyte- and neutrophil-to-lymphocyte ratios, blood pressure, and pulse together with the derived parameters.Our pilot study in first-episode psychosis patients indicates worsening of CVS health based on these parameters during the first year of treatment, the early monitoring of CVS status is highly relevant in clinical practice.


Assuntos
Transtornos Psicóticos , Biomarcadores , Pressão Sanguínea , Hemodinâmica , Humanos , Estudos Longitudinais , Neutrófilos , Projetos Piloto
3.
Eat Weight Disord ; 26(8): 2757-2761, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33559833

RESUMO

PURPOSE: People with eating disorders (EDs) have difficulties understanding their own emotions and recognizing the emotions of others, especially in ambiguous settings. We examined the neuronal mechanisms underlying the emotion processing of ambiguous interpersonal stimuli in EDs and healthy controls (HCs). METHODS: The fMRI data were acquired by a blocked experimental design with 28 women (14 EDs) during the visual presentation of a modified Thematic Apperception Test. RESULTS: EDs showed very strong associations between experienced and inferred emotions evoked by the stimuli; no such relationship was found in HCs. HCs displayed elevated left anterior insula activity during the mentalizing condition; EDs showed increased activity in the right supramarginal gyrus and medial prefrontal cortex. CONCLUSION: The two groups seem to apply different strategies for judging emotionally ambiguous stimuli, albeit resulting in equivalent judgments. We assume that activity in the supramarginal gyrus and insula in EDs is linked with suppressing their own perspective while considering emotional states, probably due to alexithymia and the lack of awareness of their own mental states. We hypothesize that the strong correlation between experienced and inferred emotions in EDs could reflect their tendency to use others as a reference point for perceiving themselves and gaining information about their affective state. LEVEL OF EVIDENCE: No level of evidence, this is a basic science study.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos , Imageamento por Ressonância Magnética , Sintomas Afetivos , Emoções , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico por imagem , Feminino , Humanos , Projetos Piloto
4.
Psychol Med ; 50(11): 1829-1838, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31439062

RESUMO

BACKGROUND: Impulsivity is a core symptom of borderline personality disorder (BPD). Impulsivity is a heterogeneous concept, and a comprehensive evaluation of impulsivity dimensions is lacking in the literature. Moreover, it is unclear whether BPD patients manifest impaired cognitive functioning that might be associated with impulsivity in another patient group, such as ADHD, a frequent comorbidity of BPD. METHODS: We tested 39 patients with BPD without major psychiatric comorbidities and ADHD, 25 patients with ADHD, and 55 healthy controls (HC) using a test battery consisting of a self-report measure of impulsivity (UPPS-P questionnaire), behavioral measures of impulsivity - impulsive action (Go/NoGo task, stop signal task) and impulsive choice (delay discounting task, Iowa gambling task), and standardized measures of attention (d2 test), working memory (digit span), and executive functioning (Tower of London). RESULTS: Patients with BPD and ADHD, as compared with HC, manifested increased self-reported impulsivity except sensation seeking and increased impulsive choice; patients with ADHD but not BPD showed increased impulsive action and deficits in cognitive functioning. Negative urgency was increased in BPD as compared to both HC and ADHD groups and correlated with BPD severity. CONCLUSIONS: Patients with BPD without ADHD comorbidity had increased self-reported impulsivity and impulsive choice, but intact impulsive action and cognitive functioning. Controlling for ADHD comorbidity in BPD samples is necessary. Negative urgency is the most diagnostically specific impulsivity dimension in BPD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Transtorno da Personalidade Borderline/psicologia , Cognição , Comportamento Impulsivo , Adolescente , Adulto , Estudos de Casos e Controles , República Tcheca , Tomada de Decisões , Função Executiva , Feminino , Humanos , Masculino , Memória de Curto Prazo , Autorrelato , Adulto Jovem
5.
Acad Psychiatry ; 44(6): 751-755, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33000447

RESUMO

OBJECTIVE: A survey among medical students of all medical schools in the Czech Republic was conducted to investigate attitudes and views of psychiatry and career choice of psychiatry. METHODS: A Czech version of the Attitudes to Psychiatry Scale (APS) and a questionnaire surveying demographic characteristics and choices of future specialty were distributed to all medical students of eight medical schools in the Czech Republic via the schools' internal communication systems in the form of an anonymous online questionnaire. RESULTS: Out of a total of 10,147 medical students in the Czech Republic (academic year 2019/2020), 2418 students participated in the survey (response rate 23.8%). Psychiatry as a non-exclusive career choice was considered by 31.3% respondents; child and adolescent psychiatry was considered by 15.4% respondents. Psychiatry as the only choice was considered by 1.6%, and child and adolescent psychiatry was not considered at all. The interest in both specialties was declining since the first year of study. The status of psychiatry among other medical specialties was perceived as low; students were rather discouraged from entering psychiatry by their families. They did not feel encouraged by their teachers to pursue career in psychiatry despite the fact that they were interested in psychiatry. They also felt uncomfortable with patients with mental illness. CONCLUSIONS: Despite high enthusiasm for psychiatry in the first year of medical school, only a small proportion of medical students consider to choose psychiatry, and especially child and adolescent psychiatry, as a career at the end of medical school.


Assuntos
Psiquiatria , Estudantes de Medicina , Adolescente , Atitude , Atitude do Pessoal de Saúde , Escolha da Profissão , Criança , República Tcheca , Humanos , Inquéritos e Questionários
6.
Neuroimage ; 193: 75-92, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30862532

RESUMO

OBJECTIVES: Emotion regulation is one of the most prevalent objectives for real-time fMRI neurofeedback (rt-fMRI-NF) studies. The existing studies differ in a number of methodological parameters. This study provides a literature review of the main parameters and results of studies using rt-fMRI-NF for emotion regulation enhancement. METHOD: A search of the Web of Science database up through November 8, 2018, identified 144 articles written in English, 89 of which were excluded as irrelevant for this study. The remaining 51 original studies and four secondary analyses of previously published original studies were included in the literature review. The selection of target brain areas, target populations, emotion regulation protocols, NF presentation, control group types, and emotion regulation instructions were examined in relation to achieved brain regulation and changes in cognitive or clinical outcomes. Study results were evaluated in terms of their statistical robustness. RESULTS: The results show that healthy people are able to regulate their brain activity in the presence of rt-fMRI-NF from various brain regions related to emotion regulation, including the amygdala, anterior insula, and anterior cingulate cortex. The regulation of brain activity using rt-fMRI-NF from prefrontal-limbic connectivity or from individually navigated brain areas is feasible as well. Most studies that used a control group show that rt-fMRI-NF actually induces some effects on brain regulation, cognitive variables, and clinical variables. Generally, the success of ROI regulation during NF training is related to the combination of target brain region, the type of emotion regulation task, and the population undergoing the training. In terms of patient groups, the strongest support for the beneficial effects of rt-fMRI-NF has been shown in increased positive emotion experiencing in patients with depression and in decreased anxiety in patients with anxiety disorders. Symptom reduction following NF training has been also reported in patients with PTSD, BPD, and schizophrenia, but direct comparisons with control groups in these studies makes it impossible to evaluate the added value of NF. Studies often do not report all the relevant analyses for evaluating NF success and many studies lack statistical robustness. CONCLUSIONS: Overall, rt-fMRI-NF seems a promising tool for emotion regulation enhancement with the potential to induce long-term symptom reduction in patients with various mental disorders. Preplanning of statistical analyses, careful interpretations of the results, and evaluations of the NF effect on symptom reduction in patient groups is recommended.


Assuntos
Encéfalo/fisiologia , Emoções/fisiologia , Imageamento por Ressonância Magnética/métodos , Transtornos Mentais/terapia , Neurorretroalimentação/métodos , Humanos
7.
Hum Brain Mapp ; 40(4): 1114-1138, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30403309

RESUMO

This study examines the impact of using different cerebrospinal fluid (CSF) and white matter (WM) nuisance signals for data-driven filtering of functional magnetic resonance imaging (fMRI) data as a cleanup method before analyzing intrinsic brain fluctuations. The routinely used temporal signal-to-noise ratio metric is inappropriate for assessing fMRI filtering suitability, as it evaluates only the reduction of data variability and does not assess the preservation of signals of interest. We defined a new metric that evaluates the preservation of selected neural signal correlates, and we compared its performance with a recently published signal-noise separation metric. These two methods provided converging evidence of the unfavorable impact of commonly used filtering approaches that exploit higher numbers of principal components from CSF and WM compartments (typically 5 + 5 for CSF and WM, respectively). When using only the principal components as nuisance signals, using a lower number of signals results in a better performance (i.e., 1 + 1 performed best). However, there was evidence that this routinely used approach consisting of 1 + 1 principal components may not be optimal for filtering resting-state (RS) fMRI data, especially when RETROICOR filtering is applied during the data preprocessing. The evaluation of task data indicated the appropriateness of 1 + 1 principal components, but when RETROICOR was applied, there was a change in the optimal filtering strategy. The suggested change for extracting WM (and also CSF in RETROICOR-corrected RS data) is using local signals instead of extracting signals from a large mask using principal component analysis.


Assuntos
Artefatos , Encéfalo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Mapeamento Encefálico/métodos , Líquido Cefalorraquidiano , Humanos , Substância Branca
8.
Neural Comput ; 31(5): 897-918, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30883275

RESUMO

Machine learning (ML) is a growing field that provides tools for automatic pattern recognition. The neuroimaging community currently tries to take advantage of ML in order to develop an auxiliary diagnostic tool for schizophrenia diagnostics. In this letter, we present a classification framework based on features extracted from magnetic resonance imaging (MRI) data using two automatic whole-brain morphometry methods: voxel-based (VBM) and deformation-based morphometry (DBM). The framework employs a random subspace ensemble-based artificial neural network classifier-in particular, a multilayer perceptron (MLP). The framework was tested on data from first-episode schizophrenia patients and healthy controls. The experiments differed in terms of feature extraction methods, using VBM, DBM, and a combination of both morphometry methods. Thus, features of different types were available for model adaptation. As we expected, the combination of features increased the MLP classification accuracy up to 73.12%-an improvement of 5% versus MLP-based only on VBM or DBM features. To further verify the findings, other comparisons using support vector machines in place of MLPs were made within the framework. However, it cannot be concluded that any classifier was better than another.


Assuntos
Encéfalo/diagnóstico por imagem , Diagnóstico por Computador/métodos , Imageamento por Ressonância Magnética , Redes Neurais de Computação , Esquizofrenia/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Reconhecimento Automatizado de Padrão/métodos
9.
J Cell Physiol ; 233(1): 530-548, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28300292

RESUMO

Although histone acetylation is one of the most widely studied epigenetic modifications, there is still a lack of information regarding how the acetylome is regulated during brain development and pathophysiological processes. We demonstrate that the embryonic brain (E15) is characterized by an increase in H3K9 acetylation as well as decreases in the levels of HDAC1 and HDAC3. Moreover, experimental induction of H3K9 hyperacetylation led to the overexpression of NCAM in the embryonic cortex and depletion of Sox2 in the subventricular ependyma, which mimicked the differentiation processes. Inducing differentiation in HDAC1-deficient mouse ESCs resulted in early H3K9 deacetylation, Sox2 downregulation, and enhanced astrogliogenesis, whereas neuro-differentiation was almost suppressed. Neuro-differentiation of (wt) ESCs was characterized by H3K9 hyperacetylation that was associated with HDAC1 and HDAC3 depletion. Conversely, the hippocampi of schizophrenia-like animals showed H3K9 deacetylation that was regulated by an increase in both HDAC1 and HDAC3. The hippocampi of schizophrenia-like brains that were treated with the cannabinoid receptor-1 inverse antagonist AM251 expressed H3K9ac at the level observed in normal brains. Together, the results indicate that co-regulation of H3K9ac by HDAC1 and HDAC3 is important to both embryonic brain development and neuro-differentiation as well as the pathophysiology of a schizophrenia-like phenotype.


Assuntos
Encéfalo/enzimologia , Histona Desacetilase 1/metabolismo , Histona Desacetilases/metabolismo , Histonas/metabolismo , Neurogênese , Neurônios/enzimologia , Esquizofrenia/enzimologia , Acetilação , Animais , Antipsicóticos/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/embriologia , Encéfalo/patologia , Antagonistas de Receptores de Canabinoides/farmacologia , Modelos Animais de Doenças , Epigênese Genética , Regulação da Expressão Gênica no Desenvolvimento , Idade Gestacional , Histona Desacetilase 1/antagonistas & inibidores , Histona Desacetilase 1/genética , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/genética , Acetato de Metilazoximetanol , Camundongos Endogâmicos C57BL , Moléculas de Adesão de Célula Nervosa/genética , Moléculas de Adesão de Célula Nervosa/metabolismo , Neurogênese/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/patologia , Processamento de Proteína Pós-Traducional , Ratos Sprague-Dawley , Receptor CB1 de Canabinoide/antagonistas & inibidores , Receptor CB1 de Canabinoide/metabolismo , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Esquizofrenia/induzido quimicamente , Esquizofrenia/tratamento farmacológico , Esquizofrenia/genética , Transdução de Sinais , Fatores de Tempo
10.
Neuroimage ; 155: 10-24, 2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28428048

RESUMO

One of the biggest problems in automated diagnosis of psychiatric disorders from medical images is the lack of sufficiently large samples for training. Sample size is especially important in the case of highly heterogeneous disorders such as schizophrenia, where machine learning models built on relatively low numbers of subjects may suffer from poor generalizability. Via multicenter studies and consortium initiatives researchers have tried to solve this problem by combining data sets from multiple sites. The necessary sharing of (raw) data is, however, often hindered by legal and ethical issues. Moreover, in the case of very large samples, the computational complexity might become too large. The solution to this problem could be distributed learning. In this paper we investigated the possibility to create a meta-model by combining support vector machines (SVM) classifiers trained on the local datasets, without the need for sharing medical images or any other personal data. Validation was done in a 4-center setup comprising of 480 first-episode schizophrenia patients and healthy controls in total. We built SVM models to separate patients from controls based on three different kinds of imaging features derived from structural MRI scans, and compared models built on the joint multicenter data to the meta-models. The results showed that the combined meta-model had high similarity to the model built on all data pooled together and comparable classification performance on all three imaging features. Both similarity and performance was superior to that of the local models. We conclude that combining models is thus a viable alternative that facilitates data sharing and creating bigger and more informative models.


Assuntos
Conjuntos de Dados como Assunto , Estudos Multicêntricos como Assunto , Neuroimagem/métodos , Esquizofrenia/diagnóstico por imagem , Máquina de Vetores de Suporte , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Reconhecimento Automatizado de Padrão/métodos
11.
Mov Disord ; 32(5): 757-768, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28186664

RESUMO

BACKGROUND: Although dystonia is traditionally conceptualized as a basal ganglia disorder, increasing interest has been directed at a different neural network node, the cerebellum, which may play a significant role in the pathophysiology of dystonia. Abnormal sensorimotor processing and disturbed motor schemes, possibly attributable to cerebellar changes, remain unclear. METHODS: We sought to characterize the extent of cerebellar dysfunction within the motor network using functional MRI activation analysis, connectivity analysis, and voxel-based morphometry in cervical dystonia patients (n = 25, 15 women, mean age 45.8 years) and healthy volunteers (n = 25, 15 women, mean age 44.7 years) in a visuospatial task requiring predictive motor timing. RESULTS: Cervical dystonia patients showed decreased activation in the posterior cerebellar lobules as well as in the premotor areas, the associative parietal cortex, and visual regions. Patients also had decreased cerebellar connectivity with bilateral basal ganglia structures and the dorsolateral prefrontal cortex. CONCLUSIONS: This promotes the view that dystonia results from miscommunication between the basal ganglia and cerebellar loops, thus providing new insights into the brain regions essential for the development of cervical dystonia. © 2017 International Parkinson and Movement Disorder Society.


Assuntos
Gânglios da Base/fisiopatologia , Cerebelo/fisiopatologia , Córtex Motor/fisiopatologia , Processamento Espacial , Torcicolo/fisiopatologia , Adulto , Gânglios da Base/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Cerebelo/diagnóstico por imagem , Feminino , Neuroimagem Funcional , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Motor/diagnóstico por imagem , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Análise e Desempenho de Tarefas , Torcicolo/diagnóstico por imagem , Adulto Jovem
12.
BMC Psychiatry ; 17(1): 104, 2017 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-28327118

RESUMO

BACKGROUND: In the postpartum period, certain groups of women are at a higher risk for developing depressive episodes. Several studies have described risk factors for developing postpartum depression (PPD). However, these studies have used limited numbers of participants, and therefore the estimated prevalence of PPD varies greatly. METHODS: The objective of this study is to identify the main risk factors for developing PPD by using data collected via the Czech version of the European Longitudinal Study of Pregnancy and Childhood (ELSPAC). This database provides a representative sample (n = 7589) observed prospectively and a large amount of data on depressive symptoms and on biological, socioeconomic, and environmental factors. The Edinburgh Postnatal Depression Scale (EPDS) was used to screen for incidence of PPD. The affective pathology was examined at three time points: before delivery, 6 weeks after delivery, and 6 months after delivery. RESULTS: The prevalence of depressive symptoms before delivery was 12.8%, 6 weeks after delivery 11.8%, and 6 months after delivery 10.1%. The prevalence rates are based on women who completed questionnaires at all three time-points (N = 3233). At all three time points, the main risk factors for developing PPD identified as significant by both univariate and multivariate analysis were personal history of depressive episodes and mothers experiencing psychosocial stressors. Other risk factors occurring in both types of analysis were: family history of depression from expectant mother's paternal side (prenatal), mothers living without partners (6 weeks postpartum) and feelings of unhappiness about being pregnant (6 months postpartum). Several protective factors were also observed: male child gender (prenatal), primiparous mothers (6 months postpartum), and secondary education (prenatal, only by multivariate analysis). Significant risk factors found solely by univariate analysis were family history of depression in both parents of the expectant mother (prenatal and 6 weeks postpartum), family history of depression from subject's maternal side (6 months postpartum), unintentional pregnancy (prenatal and 6 weeks postpartum), feelings of unhappiness about being pregnant (prenatal and 6 weeks postpartum), primary education (prenatal and 6 weeks postpartum), mothers who opted not to breastfeed (6 months postpartum) and mothers living without partners (prenatal and 6 months postpartum). Family savings were identified as protective factor (prenatal and 6 months postpartum). CONCLUSIONS: We identified significant predictors of PPD. These predictors can be easily detected in clinical practice, and systematic screening can lead to identifying potentially at risk mothers. Since the risk is linked with experience of psychosocial stressors it seems that they might benefit from increased psychosocial support to prevent affective pathology.


Assuntos
Parto Obstétrico/psicologia , Depressão Pós-Parto/epidemiologia , Depressão Pós-Parto/psicologia , Fatores Socioeconômicos , Adulto , Estudos Transversais , República Tcheca , Depressão Pós-Parto/diagnóstico , Feminino , Inquéritos Epidemiológicos , Humanos , Estudos Longitudinais , Gravidez , Estudos Prospectivos , Fatores de Proteção , Fatores de Risco
13.
Neural Plast ; 2016: 2073454, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27019753

RESUMO

Time perception is an essential part of our everyday lives, in both the prospective and the retrospective domains. However, our knowledge of temporal processing is mainly limited to the networks responsible for comparing or maintaining specific intervals or frequencies. In the presented fMRI study, we sought to characterize the neural nodes engaged specifically in predictive temporal analysis, the estimation of the future position of an object with varying movement parameters, and the contingent neuroanatomical signature of differences in behavioral performance between genders. The established dominant cerebellar engagement offers novel evidence in favor of a pivotal role of this structure in predictive short-term timing, overshadowing the basal ganglia reported together with the frontal cortex as dominant in retrospective temporal processing in the subsecond spectrum. Furthermore, we discovered lower performance in this task and massively increased cerebellar activity in women compared to men, indicative of strategy differences between the genders. This promotes the view that predictive temporal computing utilizes comparable structures in the retrospective timing processes, but with a definite dominance of the cerebellum.


Assuntos
Encéfalo/fisiologia , Percepção de Movimento/fisiologia , Percepção do Tempo/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Vias Neurais/fisiologia
14.
Cerebellum ; 14(2): 142-50, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25205331

RESUMO

The proceedings of the workshop synthesize the experimental, preclinical, and clinical data suggesting that the cerebellum, basal ganglia (BG), and their connections play an important role in pathophysiology of various movement disorders (like Parkinson's disease and atypical parkinsonian syndromes) or neurodevelopmental disorders (like autism). The contributions from individual distinguished speakers cover the neuroanatomical research of complex networks, neuroimaging data showing that the cerebellum and BG are connected to a wide range of other central nervous system structures involved in movement control. Especially, the cerebellum plays a more complex role in how the brain functions than previously thought.


Assuntos
Gânglios da Base/fisiologia , Cerebelo/fisiologia , Córtex Cerebral/fisiologia , Animais , Transtorno Autístico/fisiopatologia , Gânglios da Base/anatomia & histologia , Gânglios da Base/patologia , Gânglios da Base/fisiopatologia , Cerebelo/anatomia & histologia , Cerebelo/patologia , Cerebelo/fisiopatologia , Córtex Cerebral/anatomia & histologia , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , República Tcheca , Humanos , Atividade Motora/fisiologia , Vias Neurais/anatomia & histologia , Vias Neurais/patologia , Vias Neurais/fisiologia , Vias Neurais/fisiopatologia
15.
Cerebellum ; 13(4): 415-24, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24550129

RESUMO

Deficits in the execution of a sequence of movements are common in schizophrenia. Previous studies reported reduced functional activity in the motor cortex and cerebellum in schizophrenic patients with deficits in movement sequencing. The corticospinal tract (CST) and superior cerebellar peduncle (SCP) are fiber tracts that are involved in movement sequencing. However, the integrity of these tracts has not been evaluated in schizophrenic patients with respect to the performance of movement sequencing yet. Diffusion tensor magnetic resonance images (DT-MRI) were acquired from 24 patients with schizophrenia and 23 matched control subjects. Tractography was applied to reconstruct the CST and SCP and DT-MRI-specific parameters such as fractional anisotropy (FA) and radial diffusivity (RD) were reported. The patient group was further subdivided based on the score of sequencing of complex motor acts subscale of the Neurological Evaluation Scale into those with deficits in sequencing motor acts, the SQ(abn) group (n = 7), and those with normal performance, the SQ(norm) group (n = 17). Schizophrenia patients of the SQ(norm) subgroup had significantly reduced FA and increased RD values in the right CST in comparison to the control group; the SQ(abn) subgroup did not differ from the controls. However, the SQ(abn) subgroup showed impaired integrity of the left SCP, whereas the SQ(norm) subgroup did not. Abnormalities in the right CST in the SQ(norm) and in the left SCP in SQ(abn) groups suggest that the patients with SQ(abn) represent subgroups with distinct deficits. Moreover, these results demonstrate the involvement of the SCP in the pathogenesis of movement sequencing in schizophrenia.


Assuntos
Cerebelo/patologia , Transtornos dos Movimentos/patologia , Ponte/patologia , Esquizofrenia/patologia , Substância Branca/patologia , Adulto , Análise de Variância , Anisotropia , Estudos de Casos e Controles , Imagem de Tensor de Difusão , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Movimento/fisiologia , Transtornos dos Movimentos/etiologia , Vias Neurais/patologia , Exame Neurológico , Esquizofrenia/complicações , Adulto Jovem
16.
Hum Brain Mapp ; 34(3): 726-37, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23520601

RESUMO

OBJECTIVES: Abnormal task-related activation and connectivity is present in schizophrenia. The aim of this study was the analysis of functional networks in schizophrenia patients in remission after the first episode. EXPERIMENTAL DESIGN: Twenty-nine male patients in remission after the first episode of schizophrenia and 22 healthy controls underwent examination by functional magnetic resonance during verbal fluency tasks (VFT). The functional connectivity of brain networks was analyzed using independent component analysis. RESULTS: The patients showed lower activation of the salience network during VFT. They also showed lower deactivation of the default mode network (DMN) during VFT processing. Spectral analysis of the component time courses showed decreased power in slow frequencies of signal fluctuations in the salience and DMNs and increased power in higher frequencies in the left frontoparietal cortex reflecting higher fluctuations of the network activity. Moreover, there was decreased similarity of component time courses in schizophrenia­the patients had smaller negative correlation between VFT activated and deactivated networks, and smaller positive correlations between DMN subcomponents. CONCLUSIONS: There is still an abnormal functional connectivity of several brain networks in remission after the first episode of schizophrenia. The effect of different treatment modalities on brain connectivity, together with temporal dynamics of this functional abnormality should be the objective of further studies to assess its potential as a marker of disease stabilization.


Assuntos
Mapeamento Encefálico , Encéfalo/patologia , Vias Neurais/patologia , Esquizofrenia/patologia , Adulto , Encéfalo/irrigação sanguínea , Lateralidade Funcional , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Oxigênio/sangue , Análise de Componente Principal , Escalas de Graduação Psiquiátrica , Adulto Jovem
17.
Neural Plast ; 2013: 908741, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24198973

RESUMO

Traditionally, the pathophysiology of cervical dystonia has been regarded mainly in relation to neurochemical abnormities in the basal ganglia. Recently, however, substantial evidence has emerged for cerebellar involvement. While the absence of neurological "cerebellar signs" in most dystonia patients may be considered at least provoking, there are more subtle indications of cerebellar dysfunction in complex, demanding tasks. Specifically, given the role of the cerebellum in the neural representation of time, in the millisecond range, dysfunction to this structure is considered to be of greater importance than dysfunction of the basal ganglia. In the current study, we investigated the performance of cervical dystonia patients on a computer task known to engage the cerebellum, namely, the interception of a moving target with changing parameters (speed, acceleration, and angle) with a simple response (pushing a button). The cervical dystonia patients achieved significantly worse results than a sample of healthy controls. Our results suggest that the cervical dystonia patients are impaired at integrating incoming visual information with motor responses during the prediction of upcoming actions, an impairment we interpret as evidence of cerebellar dysfunction.


Assuntos
Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Percepção do Tempo/fisiologia , Torcicolo/congênito , Adulto , Idoso , Gânglios da Base/fisiopatologia , Cerebelo/fisiopatologia , Distonia/congênito , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Motor/fisiopatologia , Tempo de Reação/fisiologia , Torcicolo/fisiopatologia
18.
Heliyon ; 9(10): e21173, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37916075

RESUMO

The aim of this pilot study was to find whether the dysregulation of neuroendocrine biomarker signaling pathways in the first episode of non-affective psychosis is a predictive factor of treatment outcome. Patients with the first episode of non-affective psychosis (N = 29) were examined at admission, at discharge, and at follow-up (N = 23). The biomarkers included serum aldosterone, cortisol, free thyroxine, thyroid stimulating hormone, and prolactin. We revealed lower baseline aldosterone and higher baseline cortisol concentrations in patients with very good outcome compared to those with good outcome after one year. We failed to reveal any significant association between treatment outcome and neurohumoral biomarkers in the whole sample at 1-year follow-up. However, baseline aldosterone concentrations negatively correlated with total PANSS scores at the discharge. Lower baseline aldosterone and higher baseline cortisol concentrations have the potential to predict a more favorable outcome for patients with the first episode of psychosis.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38037120

RESUMO

BACKGROUND: Interpersonal difficulties of patients with borderline personality disorder (BPD) are closely related to rejection sensitivity. The aim of the present study was to gain further insight into the experience and cerebral processing of social interactions in patients with BPD by using fMRI during experimentally induced experiences of social exclusion, inclusion, and overinclusion. METHODS: The study involved 30 participants diagnosed with BPD (29 female and 1 male; age: M = 24.22, SD = 5.22) and 30 healthy controls (29 female and 1 male; age: M = 24.66, SD = 5.28) with no current or lifetime psychiatric diagnoses. In the fMRI session, all participants were asked to complete a Cyberball task that consisted of an alternating sequence of inclusion, exclusion, and overinclusion conditions. RESULTS: Compared to healthy controls, participants with BPD reported higher levels of inner tension and more unpleasant emotions across all experimental conditions. At the neural level, the participants with BPD showed lower recruitment of the left hippocampus in response to social exclusion (relative to the inclusion condition) than the healthy controls did. Lower recruitment of the left hippocampus in this contrast was associated with childhood maltreatment in patients with BPD. However, this difference was no longer significant when we added the covariate of hippocampal volume to the analysis. During social overinclusion (relative to the inclusion condition), we observed no significant differences in a group comparison of neural activation. CONCLUSIONS: The results of our study suggest that patients with BPD experience more discomfort than do healthy controls during social interactions. Compared to healthy participants, patients with BPD reported more inner tension and unpleasant emotions, irrespective of the extent to which others included them in social interactions. At a neural level, the participants with BPD showed a lower recruitment of the left hippocampus in response to social exclusion than the healthy controls did. The reduced activation of this neural structure could be related to a history of childhood maltreatment and smaller hippocampal volume in patients with BPD.

20.
Crit Care Med ; 40(2): 484-90, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22001583

RESUMO

OBJECTIVE: To describe the epidemiology and time spectrum of delirium using Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria and to validate a tool for delirium assessment in patients in the acute poststroke period. DESIGN: A prospective observational cohort study. SETTING: The stroke unit of a university hospital. PATIENTS: A consecutive series of 129 patients with stroke (with infarction or intracerebral hemorrhage, 57 women and 72 men; mean age, 72.5 yrs; age range, 35-93 yrs) admitted to the stroke unit of a university hospital were evaluated for delirium incidence. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Criterion validity and overall accuracy of the Czech version of the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) were determined using serial daily delirium assessments with CAM-ICU by a junior physician compared with delirium diagnosis by delirium experts using the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria that began the first day after stroke onset and continued for at least 7 days. Cox regression models using time-dependent covariate analysis adjusting for age, gender, prestroke dementia, National Institutes of Stroke Health Care at admission, first-day Sequential Organ Failure Assessment, and asphasia were used to understand the relationships between delirium and clinical outcomes. An episode of delirium based on reference Diagnostic and Statistical Manual assessment was detected in 55 patients with stroke (42.6%). In 37 of these (67.3%), delirium began within the first day and in all of them within 5 days of stroke onset. A total of 1003 paired CAM-ICU/Diagnostic and Statistical Manual of Mental Disorders daily assessments were completed. Compared with the reference standard for diagnosing delirium, the CAM-ICU demonstrated a sensitivity of 76% (95% confidence interval [CI] 55% to 91%), a specificity of 98% (95% CI 93% to 100%), an overall accuracy of 94% (95% CI 88% to 97%), and high interrater reliability (κ = 0.94; 95% CI 0.83-1.0). The likelihood ratio of the CAM-ICU in the diagnosis of delirium was 47 (95% CI 27-83). Delirium was an independent predictor of increased length of hospital stay (hazard ratio 1.63; 95% CI 1.11-2.38; p = .013). CONCLUSIONS: Poststroke delirium may frequently be detected provided that the testing algorithm is appropriate to the time profile of poststroke delirium. Early (first day after stroke onset) and serial screening for delirium is recommended. CAM-ICU is a valid instrument for the diagnosis of delirium and should be considered an aid in delirium screening and assessment in future epidemiologic and interventional studies in patients with stroke.


Assuntos
Delírio/diagnóstico , Delírio/epidemiologia , Unidades de Terapia Intensiva , Testes Neuropsicológicos , Acidente Vascular Cerebral/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Confusão/classificação , Cuidados Críticos/métodos , Delírio/terapia , Progressão da Doença , Feminino , Seguimentos , Hospitais Universitários , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Reprodutibilidade dos Testes , Medição de Risco , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/terapia , Taxa de Sobrevida
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