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Machine learning can be used to define subtypes of psychiatric conditions based on shared biological foundations of mental disorders. Here we analyzed cross-sectional brain images from 4,222 individuals with schizophrenia and 7038 healthy subjects pooled across 41 international cohorts from the ENIGMA, non-ENIGMA cohorts and public datasets. Using the Subtype and Stage Inference (SuStaIn) algorithm, we identify two distinct neurostructural subgroups by mapping the spatial and temporal 'trajectory' of gray matter change in schizophrenia. Subgroup 1 was characterized by an early cortical-predominant loss with enlarged striatum, whereas subgroup 2 displayed an early subcortical-predominant loss in the hippocampus, striatum and other subcortical regions. We confirmed the reproducibility of the two neurostructural subtypes across various sample sites, including Europe, North America and East Asia. This imaging-based taxonomy holds the potential to identify individuals with shared neurobiological attributes, thereby suggesting the viability of redefining existing disorder constructs based on biological factors.
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Algoritmos , Substância Cinzenta , Imageamento por Ressonância Magnética , Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/patologia , Masculino , Feminino , Adulto , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Aprendizado de Máquina , Pessoa de Meia-Idade , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Estudos Transversais , Europa (Continente) , Neuroimagem , Reprodutibilidade dos Testes , América do Norte , Hipocampo/diagnóstico por imagem , Hipocampo/patologiaRESUMO
Accessible Summary What is known on the subject? Functioning is one of the most affected areas in schizophrenia. Social, occupational and personal domains are affected, and these deficits are responsible for a major part of the disability associated with the disorder. There are several instruments to measure functioning, but the HoNOS provides a wide assessment of impairment in 12 areas of functioning. What does the paper add to existing knowledge? The Spanish version of the HoNOS shows good properties in terms of reliability and validity for use in schizophrenia patients. Although some authors divide the scale according to proposed underlying dimensions, in schizophrenia this division may not be appropriate. What are the implications for practice? A reliable and easy-to-use measure of impairment in different areas of functioning is useful for optimizing the treatment and rehabilitation of patients with schizophrenia. ABSTRACT: INTRODUCTION: The HoNOS scale was designed for the assessment of psychosocial impairment in various domains. While it is widely used in psychiatric settings, it has not been validated in Spanish for use in patients with schizophrenia. AIM: To examine the psychometric properties of the Spanish version of the HoNOS scale in a sample of schizophrenia patients. METHOD: A total of 194 individuals aged 18 to 65 with schizophrenia spectrum diagnoses were evaluated using the HoNOS. Illness severity and level of functioning were also assessed. RESULTS: The HoNOS showed moderate internal consistency, good inter-observer reliability and good test-retest reliability. Factor analysis revealed an internal structure consisting of four factors, with item distribution differing from the theoretical dimensions proposed for the original scale. DISCUSSION: The Spanish version of the HoNOS scale is a reliable and valid instrument for assessing psychosocial impairment in individuals diagnosed with schizophrenia spectrum disorders. However, further research is needed to determine its internal structure more accurately. IMPLICATIONS FOR PRACTICE: The HoNOS scale provides researchers and clinicians with a valid measure of impairment in twelve different domains, which can facilitate and guide the treatment of schizophrenia patients.
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BACKGROUND: The clinical course following a first episode of schizophrenia (FES) is often characterized by recurrent relapses, resulting in unfavorable clinical and functional outcomes. Inflammatory dysregulation has been implicated in relapse risk; however, the predictive value of inflammatory blood cells in clinically remitted patients after a FES has not been previously explored. METHODS: In this study, we closely monitored 111 patients in remission after a FES until relapse or a three-year follow-up endpoint. The participants were recruited from the multicenter 2EPS Project. Data on inflammatory blood cells and ratios were collected at baseline and at the time of relapse or after three years of follow-up. RESULTS: Monocyte counts (OR = 1.91; 95 % CI = 1.07-3.18; p = 0.009) and basophil counts (OR = 1.09; 95 % CI = 1.01-1.12; p = 0.005) at baseline were associated with an increased risk of relapse, while the platelet-lymphocyte ratio (OR = 0.98; 95 % CI = 0.97-0.99; p = 0.019) was identified as a protective factor. However, after adjusting for cannabis and tobacco use during the follow-up, only monocyte counts (OR = 1.73; 95 % CI = 1.03-2.29; p = 0.027) and basophil counts (OR = 1.08; 95 % CI = 1.01-1.14; p = 0.008) remained statistically significant. ROC curve analysis indicated that the optimal cut-off values for discriminating relapsers were 0.52 × 10^9/L (AUC: 0.66) for monocytes and 0.025 × 10^9/L (AUC: 0.75) for basophils. When considering baseline inflammatory levels, no significant differences were observed in the inflammatory biomarkers at the endpoint between relapsers and non-relapsers. CONCLUSION: This study provides evidence that higher monocyte and basophil counts measured at remission after a FES are associated with an increased risk of relapse during a three-year follow-up period.
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Basófilos , Monócitos , Recidiva , Esquizofrenia , Humanos , Masculino , Feminino , Adulto , Seguimentos , Esquizofrenia/sangue , Adulto Jovem , Contagem de Leucócitos , Transtornos Psicóticos/sangue , Inflamação/sangue , Adolescente , PrognósticoRESUMO
BACKGROUND: Schizophrenic symptoms are known to segregate into reality distortion, negative and disorganization syndromes, but the correlates of these syndromes with regional brain structural change are not well established. Cognitive impairment is a further clinical feature of schizophrenia, whose brain structural correlates are the subject of conflicting findings. METHODS: 165 patients with schizophrenia were rated for symptoms using the PANSS, and cognitive impairment was indexed by estimated premorbid-current IQ discrepancy. Cortical volume was measured using surface-based morphometry in the patients and in 50 healthy controls. Correlations between clinical and cognitive measures and cortical volume were examined using whole-brain FreeSurfer tools. RESULTS: No clusters of volume reduction were seen associated with reality distortion or disorganization. Negative symptom scores showed a significant inverse correlation with volume in a small cluster in the left medial orbitofrontal gyrus. Larger estimated premorbid-current IQ discrepancies were associated with clusters of reduced cortical volume in the left precentral gyrus and the left temporal lobe. The cluster of association with negative symptoms disappeared when estimated premorbid-current IQ discrepancy was controlled for. CONCLUSIONS: This study does not provide support for an association between brain structural abnormality and reality distortion or disorganization syndromes in schizophrenia. The cluster of volume reduction found in the left medial orbitofrontal cortex correlated with negative symptoms may have reflected the association between this class of symptoms and cognitive impairment. The study adds to existing findings of an association between cognitive impairment and brain structural changes in the disorder.
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Disfunção Cognitiva , Esquizofrenia , Humanos , Esquizofrenia/complicações , Esquizofrenia/diagnóstico por imagem , Encéfalo , Lobo Frontal , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Lobo Temporal , Imageamento por Ressonância MagnéticaRESUMO
Machine learning can be used to define subtypes of psychiatric conditions based on shared clinical and biological foundations, presenting a crucial step toward establishing biologically based subtypes of mental disorders. With the goal of identifying subtypes of disease progression in schizophrenia, here we analyzed cross-sectional brain structural magnetic resonance imaging (MRI) data from 4,291 individuals with schizophrenia (1,709 females, age=32.5 years±11.9) and 7,078 healthy controls (3,461 females, age=33.0 years±12.7) pooled across 41 international cohorts from the ENIGMA Schizophrenia Working Group, non-ENIGMA cohorts and public datasets. Using a machine learning approach known as Subtype and Stage Inference (SuStaIn), we implemented a brain imaging-driven classification that identifies two distinct neurostructural subgroups by mapping the spatial and temporal trajectory of gray matter (GM) loss in schizophrenia. Subgroup 1 (n=2,622) was characterized by an early cortical-predominant loss (ECL) with enlarged striatum, whereas subgroup 2 (n=1,600) displayed an early subcortical-predominant loss (ESL) in the hippocampus, amygdala, thalamus, brain stem and striatum. These reconstructed trajectories suggest that the GM volume reduction originates in the Broca's area/adjacent fronto-insular cortex for ECL and in the hippocampus/adjacent medial temporal structures for ESL. With longer disease duration, the ECL subtype exhibited a gradual worsening of negative symptoms and depression/anxiety, and less of a decline in positive symptoms. We confirmed the reproducibility of these imaging-based subtypes across various sample sites, independent of macroeconomic and ethnic factors that differed across these geographic locations, which include Europe, North America and East Asia. These findings underscore the presence of distinct pathobiological foundations underlying schizophrenia. This new imaging-based taxonomy holds the potential to identify a more homogeneous sub-population of individuals with shared neurobiological attributes, thereby suggesting the viability of redefining existing disorder constructs based on biological factors.
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Schizophrenia may represent a trade-off in the evolution of human-specific ontogenetic mechanisms that guide neurodevelopment. Human Accelerated Regions (HARs) are evolutionary markers functioning as neurodevelopmental transcription enhancers that have been associated with brain configuration, neural information processing, and schizophrenia risk. Here, we have investigated the influence of HARs' polygenic load on neuroanatomical measures through a case-control approach (128 patients with schizophrenia and 115 controls). To this end, we have calculated the global schizophrenia Polygenic Risk Score (Global PRSSZ) and that specific to HARs (HARs PRSSZ). We have also estimated the polygenic burden restricted to the HARs linked to transcriptional regulatory elements active in the foetal brain (FB-HARs PRSSZ) and the adult brain (AB-HARs PRSSZ). We have explored the main effects of the PRSs and the PRSs x diagnosis interactions on brain regional cortical thickness (CT) and surface area (SA). The results indicate that a higher FB-HARs PRSSZ is associated with patients' lower SA in the lateral orbitofrontal cortex, the superior temporal cortex, the pars triangularis and the paracentral lobule. While noHARs-derived PRSs show an effect on the risk, our neuroanatomical findings suggest that the human-specific transcriptional regulation during the prenatal period underlies SA variability, highlighting the role of these evolutionary markers in the schizophrenia genomic architecture.
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Esquizofrenia , Adulto , Humanos , Esquizofrenia/genética , Encéfalo/diagnóstico por imagem , Córtex Pré-Frontal , Herança Multifatorial , Regulação da Expressão GênicaRESUMO
Little is known about genetic predisposition to relapse. Previous studies have linked cognitive and psychopathological (mainly schizophrenia and bipolar disorder) polygenic risk scores (PRS) with clinical manifestations of the disease. This study aims to explore the potential role of PRS from major mental disorders and cognition on schizophrenia relapse. 114 patients recruited in the 2EPs Project were included (56 patients who had not experienced relapse after 3 years of enrollment and 58 patients who relapsed during the 3-year follow-up). PRS for schizophrenia (PRS-SZ), bipolar disorder (PRS-BD), education attainment (PRS-EA) and cognitive performance (PRS-CP) were used to assess the genetic risk of schizophrenia relapse.Patients with higher PRS-EA, showed both a lower risk (OR=0.29, 95% CI [0.11-0.73]) and a later onset of relapse (30.96± 1.74 vs. 23.12± 1.14 months, p=0.007. Our study provides evidence that the genetic burden of neurocognitive function is a potentially predictors of relapse that could be incorporated into future risk prediction models. Moreover, appropriate treatments for cognitive symptoms appear to be important for improving the long-term clinical outcome of relapse.
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BACKGROUND: A leading theory of the negative symptoms of schizophrenia is that they reflect reduced responsiveness to rewarding stimuli. This proposal has been linked to abnormal (reduced) dopamine function in the disorder, because phasic release of dopamine is known to code for reward prediction error (RPE). Nevertheless, few functional imaging studies have examined if patients with negative symptoms show reduced RPE-associated activations. METHODS: Matched groups of DSM-5 schizophrenia patients with high negative symptom scores (HNS, N = 27) or absent negative symptoms (ANS, N = 27) and healthy controls (HC, N = 30) underwent fMRI scanning while they performed a probabilistic monetary reward task designed to generate a measure of RPE. RESULTS: In the HC, whole-brain analysis revealed that RPE was positively associated with activation in the ventral striatum, the putamen, and areas of the lateral prefrontal cortex and orbitofrontal cortex, among other regions. Group comparison revealed no activation differences between the healthy controls and the ANS patients. However, compared to the ANS patients, the HNS patients showed regions of significantly reduced activation in the left ventrolateral and dorsolateral prefrontal cortex, and in the right lingual and fusiform gyrus. HNS and ANS patients showed no activation differences in ventral striatal or midbrain regions-of-interest (ROIs), but the HNS patients showed reduced activation in a left orbitofrontal cortex ROI. CONCLUSIONS: The findings do not suggest that a generalized reduction of RPE signalling underlies negative symptoms. Instead, they point to a more circumscribed dysfunction in the lateral frontal and possibly the orbitofrontal cortex.
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Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagem , Dopamina , Recompensa , Encéfalo/diagnóstico por imagem , Lobo Frontal , Imageamento por Ressonância MagnéticaRESUMO
BACKGROUND AND HYPOTHESIS: The existing developmental bond between fingerprint generation and growth of the central nervous system points to a potential use of fingerprints as risk markers in schizophrenia. However, the high complexity of fingerprints geometrical patterns may require flexible algorithms capable of characterizing such complexity. STUDY DESIGN: Based on an initial sample of scanned fingerprints from 612 patients with a diagnosis of non-affective psychosis and 844 healthy subjects, we have built deep learning classification algorithms based on convolutional neural networks. Previously, the general architecture of the network was chosen from exploratory fittings carried out with an independent fingerprint dataset from the National Institute of Standards and Technology. The network architecture was then applied for building classification algorithms (patients vs controls) based on single fingers and multi-input models. Unbiased estimates of classification accuracy were obtained by applying a 5-fold cross-validation scheme. STUDY RESULTS: The highest level of accuracy from networks based on single fingers was achieved by the right thumb network (weighted validation accuracy = 68%), while the highest accuracy from the multi-input models was attained by the model that simultaneously used images from the left thumb, index and middle fingers (weighted validation accuracy = 70%). CONCLUSION: Although fitted models were based on data from patients with a well established diagnosis, since fingerprints remain lifelong stable after birth, our results imply that fingerprints may be applied as early predictors of psychosis. Specially, if they are used in high prevalence subpopulations such as those of individuals at high risk for psychosis.
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Aprendizado Profundo , Transtornos Psicóticos , Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagem , Redes Neurais de Computação , Algoritmos , Transtornos Psicóticos/diagnóstico por imagemRESUMO
BACKGROUND: During the COVID-19 pandemic, pregnant women are exposed to potentially harmful stressors that might affect their health. The direct consequences that SARS-CoV-2 may have on perinatal mental health are still unknown. OBJECTIVE: The present study aimed to explore the impact of the COVID-19 pandemic on psychopathological symptoms in a sample of Spanish pregnant women. METHODS: A sample of 186 pregnant women was assessed using the revised Symptoms Check List-90 during the first lockdown in Spain. RESULTS: The results showed clinical scores on the obsession and compulsion, anxiety and phobic anxiety subscales, as well as on the severity indexes. Phobic anxiety was the only variable that was inversely correlated with age and the number of previous miscarriages. A linear regression model showed that age was inversely associated with phobic anxiety scores. A younger age was associated with higher levels of phobic anxiety symptoms. CONCLUSIONS: Our results indicated that younger pregnant women and women in the first trimester of pregnancy were more vulnerable to the effects of stress and concerns about COVID-19.
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COVID-19 , Gravidez , Feminino , Humanos , COVID-19/epidemiologia , SARS-CoV-2 , Pandemias , Gestantes , Espanha/epidemiologia , Controle de Doenças Transmissíveis , Transtornos de AnsiedadeRESUMO
BACKGROUND: Although executive impairment has been reported in mania, its brain functional correlates have been relatively little studied. This study examined goal management, believed to be more closely related to executive impairment in daily life than other executive tasks, using a novel functional magnetic resonance imaging (fMRI) paradigm in patients in this illness phase. METHODS: Twenty-one currently manic patients with bipolar disorder and 30 matched healthy controls were scanned while performing the Computerized Multiple Elements Test (CMET). This requires participants to sequentially play four simple games, with transition between games being made either voluntarily (executive condition) or automatically (control condition). RESULTS: CMET performance was impaired in the manic patients compared to the healthy controls. Manic patients failed to increase activation in the lateral frontal, cingulate and inferior parietal cortex when the executive demands of the task increased, while this increase was observed in the healthy controls. Activity in these regions was associated with task performance. CONCLUSIONS: Manic patients show evidence of impaired goal management, which is associated with a pattern of reduced medial and lateral frontal and parietal activity.
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Transtorno Bipolar , Humanos , Mania , Objetivos , Encéfalo , Mapeamento Encefálico , Imageamento por Ressonância MagnéticaRESUMO
BACKGROUND: The brain functional correlates of delusions have been relatively little studied. However, a virtual reality paradigm simulating travel on the London Underground has been found to evoke referential ideation in both healthy subjects and patients with schizophrenia, making brain activations in response to such experiences potentially identifiable. METHOD: Ninety patients with schizophrenia/schizoaffective disorder and 28 healthy controls underwent functional magnetic resonance imaging while they viewed virtual reality versions of full and empty Barcelona Metro carriages. RESULTS: Compared to the empty condition, viewing the full carriage was associated with activations in the visual cortex, the cuneus and precuneus/posterior cingulate cortex, the inferior parietal cortex, the angular gyrus and parts of the middle and superior temporal cortex including the temporoparietal junction bilaterally. There were no significant differences in activation between groups. Nor were there activations associated with referentiality or presence of delusions generally in the patient group. However, patients with persecutory delusions showed a cluster of reduced activation compared to those without delusions in a region in the right temporal/occipital cortex. CONCLUSIONS: Performance of the metro task is associated with a widespread pattern of activations, which does not distinguish schizophrenic patients and controls, or show an association with referentiality or delusions in general. However, the finding of a cluster of reduced activation close to the right temporoparietal junction in patients with persecutory delusions specifically is of potential interest, as this region is believed to play a role in social cognition.
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Transtornos Psicóticos , Esquizofrenia , Humanos , Delusões/diagnóstico , Esquizofrenia/complicações , Imageamento por Ressonância Magnética/métodos , EncéfaloRESUMO
The experience of auditory verbal hallucinations (AVH, "hearing voices") in schizophrenia has been found to be associated with reduced auditory cortex activation during perception of real auditory stimuli like tones and speech. We re-examined this finding using 46 patients with schizophrenia (23 with frequent AVH and 23 hallucination-free), who underwent fMRI scanning while they heard words, sentences and reversed speech. Twenty-five matched healthy controls were also examined. Perception of words, sentences and reversed speech all elicited activation of the bilateral superior temporal cortex, the inferior and lateral prefrontal cortex, the inferior parietal cortex and the supplementary motor area in the patients and the healthy controls. During the sentence and reversed speech conditions, the schizophrenia patients as a group showed reduced activation in the left primary auditory cortex (Heschl's gyrus) relative to the healthy controls. No differences were found between the patients with and without hallucinations in any condition. This study therefore fails to support previous findings that experience of AVH attenuates speech-perception-related brain activations in the auditory cortex. At the same time, it suggests that schizophrenia patients, regardless of presence of AVH, show reduced activation in the primary auditory cortex during speech perception, a finding which could reflect an early information processing deficit in the disorder.
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Córtex Auditivo , Esquizofrenia , Percepção da Fala , Humanos , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/complicações , Percepção da Fala/fisiologia , Alucinações/diagnóstico por imagem , Alucinações/complicações , Encéfalo/diagnóstico por imagem , Lobo Temporal , Imageamento por Ressonância Magnética , Córtex Auditivo/diagnóstico por imagem , Percepção AuditivaRESUMO
INTRODUCTION: Functional impairment in schizophrenia is one of the main features of the disorder and implies a great impact on the patient's quality of life. The Brief Functioning Assessment Scale (FAST), originally validated in bipolar disorder, has also been validated for its application in other mental disorders. However, we only found one study on the reliability and validity of the Brazilian version in schizophrenia. The purpose of this study was to analyze the psychometric properties of the Spanish version of the FAST in patients diagnosed with schizophrenia. MATERIAL AND METHODS: A total of 226 patients with a diagnosis of schizophrenia were evaluated by mean the FAST, the GAF and the self-care requirements scale (ERA). Scale properties were analyzed in terms of internal consistency, inter-observer agreement and test-retest reliability. Convergent validity with the GAF and ERA scales was also analyzed, as well as construct validity by means of a Confirmatory Factor Analysis (CFA). RESULTS: For the total scale, the results showed high internal consistency (Cronbach's Alpha of, 87), as well as good inter-observer (ICC=,86) and test-retest (ICC=,77) agreement. Concurrent validity with the GAF scale was discrete (r=-,32; P<,001) and with the ERA scale was moderate (r=,50; P<,001). CFA showed an internal structure that matched the six factors proposed by the original scale, with a good level of item saturation for each factor. CONCLUSIONS: The FAST scale showed good psychometric properties in terms of reliability and validity in its Spanish version for its application in patients with schizophrenia. It can be considered as a good tool to assess different areas of functional impairment in clinical practice and research.
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Esquizofrenia , Humanos , Esquizofrenia/diagnóstico , Reprodutibilidade dos Testes , Qualidade de Vida , Psicometria/métodos , Análise FatorialRESUMO
Una de las principales líneas de investigación en desarrollo sobre los primeros episodios psicóticos se centra en el estudio de biomarcadores con el objetivo de dar respuesta a cuestiones como la gran heterogeneidad clínica o el riesgo de recaídas. Sin embargo, los estudios de neuroimagen muestran resultados contradictorios y los estudios longitudinales son escasos. Por ello se ha realizado un seguimiento de entre 8 y 10 años a una cohorte de 30 pacientes con un primer episodio psicótico y un grupo equivalente de controles sanos, tanto a nivel de neuroimagen estructural como funcional durante la realización de una tarea de memoria de trabajo, la N-Back. En la evaluación inicial los PEP mostraron una reducción del volumen global y un fallo en desactivación en zonas frontales durante la realización de la N-Back, que fue más significativo en pacientes con un posterior diagnóstico de esquizofrenia. En la evaluación de seguimiento los resultados muestran un fallo en desactivación en el grupo de pacientes que se extiende a regiones parietales posteriores. Estas regiones forman la llamada red neuronal por defecto, una serie de regiones que se activan en reposo, pero que se desactivan durante la realización de tareas con una alta demanda cognitiva. Estos resultados apuntan a una disfunción progresiva de la red neural por defecto en primeros episodios, subyacentes a la progresión del trastorno, y proporcionan una mejor comprensión de la evolución de los factores fisiopatológicos que afectan a los PEP (AU)
A major developing area on first psychotic episodes (FEP) research focuses on the study of biomarkers with the aim of answering questions such as the great clinical heterogeneity or the risk of relapse. However, neuroimaging studies show contradictory results and longitudinal studies are scarce. Therefore, a cohort of 30 patients with a first psychotic episode and an equivalent group of healthy controls were followed up for 8 to 10 years, both at the structural and functional neuroimaging level during the performance of a working memory task, the N-Back. At baseline, the FEP group showed a reduced global volume and a failure to deactivate frontal areas during the N-Back task. This failure was more pronounced in patients with a later diagnosis of schizophrenia. At the follow-up assessment the results show a failure of deactivation in the patient group that extends to posterior parietal regions. These regions form the so-called default mode network, a series of regions that are activated at rest, but deactivated during the performance of cognitively demanding tasks. These results point to a progressive dysfunction of the default mode network in first episodes psychosis underlying the progression of the disorder and provide a better understanding of the evolution of pathophysiological factors affecting FEP (AU)
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Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Transtornos Psicóticos/diagnóstico por imagem , Neuroimagem Funcional , Neuropsicologia , Imageamento por Ressonância Magnética , Estudos de Casos e Controles , SeguimentosRESUMO
BACKGROUND: The negative symptoms of schizophrenia have been proposed to reflect prefrontal cortex dysfunction. However, this proposal has not been consistently supported in functional imaging studies, which have also used executive tasks that may not capture key aspects of negative symptoms such as lack of volition. METHOD: Twenty-four DSM-5 schizophrenic patients with high negative symptoms (HNS), 25 with absent negative symptoms (ANS) and 30 healthy controls underwent fMRI during performance of the Computerized Multiple Elements Test (CMET), a task designed to measure poor organization of goal directed behaviour or 'goal neglect'. Negative symptoms were rated using the PANSS and the Clinical Assessment Interview for Negative Symptoms (CAINS). RESULTS: On whole brain analysis, the ANS patients showed no significant clusters of reduced activation compared to the healthy controls. In contrast, the HNS patients showed hypoactivation compared to the healthy controls in the left anterior frontal cortex, the right dorsolateral prefrontal cortex (DLPFC), the anterior insula bilaterally and the bilateral inferior parietal cortex. When compared to the ANS patients, the HNS patients showed reduced activation in the left anterior frontal cortex, the left DLPFC and the left inferior parietal cortex. After controlling for disorganization scores, differences remained in clusters in the left anterior frontal cortex and the bilateral inferior parietal cortex. CONCLUSIONS: This study provides evidence that reduced prefrontal activation, perhaps especially in the left anterior frontal cortex, is a brain functional correlate of negative symptoms in schizophrenia. The simultaneous finding of reduced inferior parietal cortex activation was unexpected, but could reflect this region's involvement in cognitive control, particularly the 'regulative' component of this.
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Esquizofrenia , Psicologia do Esquizofrênico , Objetivos , Humanos , Imageamento por Ressonância Magnética/métodos , Córtex Pré-Frontal/diagnóstico por imagemRESUMO
Introducción: El deterioro funcional es una de las principales características del curso de la esquizofrenia e implica un gran impacto en la calidad de vida del paciente. La Escala de funcionamiento breve (FAST), validada originalmente en trastorno bipolar, también ha sido validada para su aplicación en otros trastornos mentales, aunque solo encontramos un estudio sobre la fiabilidad y validez de la versión brasileña en esquizofrenia. El propósito de este estudio fue analizar las propiedades psicométricas de la versión española de la FAST en pacientes diagnosticados de esquizofrenia.Material y métodos: Un total de 226 pacientes con diagnóstico de esquizofrenia fueron evaluados, cumplimentando la FAST, la GAF y la Escala de requisitos de autocuidado (ERA). Se analizaron las propiedades de la escala en términos de consistencia interna, concordancia interobservador y fiabilidad test-retest. Se analizó también la validez convergente con las escalas GAF y ERA, y la validez de constructo mediante un análisis factorial confirmatorio.Resultados:Para el total del cuestionario los resultados mostraron una elevada consistencia interna (Cronbach's Alpha de 0,87), así como una buena concordancia interobservador (CCI=0,86) y test-retest (CCI=0,77). La validez concurrente con la escala GAF fue discreta (r=0,32; p<0,001) y con la escala ERA moderada (r=0,50; p<0,001). El análisis factorial confirmatorio mostró una estructura interna que se ajustaba a los 6 factores de la escala original, con un buen nivel de saturación de los ítems para cada factor.Conclusiones: La escala FAST mostró buenas propiedades psicométricas en términos de fiabilidad y validez en su versión española para su aplicación en pacientes con esquizofrenia. Se puede considerar una buena herramienta para evaluar diferentes áreas del deterioro funcional en la práctica clínica y en investigación. (AU)
Introduction: Functional impairment in schizophrenia is one of the main features of the disorder and implies a great impact on the patient's quality of life. The brief functioning assessment scale (FAST), originally validated in bipolar disorder, has also been validated for its application in other mental disorders. However, we only found one study on the reliability and validity of the Brazilian version in schizophrenia. The purpose of this study was to analyze the psychometric properties of the Spanish version of the FAST in patients diagnosed with schizophrenia.Material and methods: A total of 226 patients with a diagnosis of schizophrenia were evaluated by mean the FAST, the GAF and the self-care requirements scale (ERA). Scale properties were analyzed in terms of internal consistency, inter-observer agreement and testretest reliability. Convergent validity with the GAF and ERA scales was also analyzed, as well as construct validity by means of a Confirmatory Factor Analysis (CFA).Results: For the total scale, the results showed high internal consistency (Cronbach's Alpha of .87), as well as good inter-observer (ICC=.86) and testretest (ICC=.77) agreement. Concurrent validity with the GAF scale was discrete (r=−.32; P<.001) and with the ERA scale was moderate (r=.50; P<.001). CFA showed an internal structure that matched the six factors proposed by the original scale, with a good level of item saturation for each factor.Conclusions: The FAST scale showed good psychometric properties in terms of reliability and validity in its Spanish version for its application in patients with schizophrenia. It can be considered as a good tool to assess different areas of functional impairment in clinical practice and research. (AU)
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Humanos , Adulto , Pessoa de Meia-Idade , Transtorno Bipolar , Esquizofrenia/diagnóstico , Pesos e Medidas , EspanhaRESUMO
Intimate partner violence against women (IPVAW) is a serious and overwhelming public concern. Neuroimaging techniques have provided insights into the brain mechanisms underlying IPVAW perpetration. The purpose of this study is to examine the resting-state functional connectivity (rsFC) involving the process of social decision-making of male perpetrators. Twenty-six male perpetrators convicted for an IPVAW crime were compared to 29 men convicted for crimes other than IPVAW (other offenders) and 29 men with no criminal records (non-offenders) using a seed-based approach. Seeds were located in areas involved in reflective (prefrontal), impulsive (amygdala and striatum) and interoceptive (insula) processing. Then, as an exploratory analysis, the connectivity networks on male perpetrators were correlated with measures of executive functions and socioemotional self-report measures. Male perpetrators in comparison to other offenders and non-offenders, presented higher rsFC between prefrontal, limbic, brainstem, temporal and basal ganglia areas. Also male perpetrators showed higher rsFC between insula, default mode network and basal ganglia, while lower rsFC was found between prefrontal and motor areas and between amygdala, occipital and parietal areas. Exploratory correlations suggest that the specific rsFC in male perpetrators might be more related to socioemotional processes than to executive functions. These results showed that male perpetrators present a specific rsFC in brain systems that are essential for an adaptive social decision-making.
Assuntos
Mapeamento Encefálico , Violência por Parceiro Íntimo , Tonsila do Cerebelo , Gânglios da Base , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética , MasculinoRESUMO
Regularization may be used as an alternative to dimensionality reduction when the number of variables in a model is much larger than the number of available observations. In a recent study from our group regularized regression was employed to quantify brain functional connectivity in a sample of healthy controls using a brain parcellation and resting state fMRI images. Here regularization is applied to evaluate resting state connectivity abnormalities at the voxel level in a sample of patients with schizophrenia. Specifically, ridge regression is implemented with different degrees of regularization. Results are compared to those delivered by the weighted global brain connectivity method (GBC), which is based on averaged bivariate correlations and from the non-redundant connectivity method (NRC), a dimensionality reduction approach that applies supervised principal component regressions. Ridge regression is able to detect a larger set of abnormally connected regions than both GBC and NRC methods, including schizophrenia related connectivity reductions in fronto-medial, somatosensory and occipital structures. Due to its multivariate nature, the proposed method is much more sensitive to group abnormalities than the GBC, but it also outperforms the NRC, which is multivariate too. Voxel based regularized regression is a simple and sensitive alternative for quantifying brain functional connectivity.
RESUMO
Auditory verbal hallucinations (AVH) are a key symptom of schizophrenia (SZ) defined by anomalous perception of speech. Anomalies of processing external speech stimuli have also been reported in people with AVH, but it is unexplored which specific dimensions of language are processed differently. Using a speech perception task (passive listening), we here targeted the processing of deixis, a key dimension of language governing the contextual anchoring of speech in interpersonal context. We designed naturalistic speech stimuli that were either non-personal and fact-reporting ('low-deixis' condition), or else involved rich deictic devices such as the grammatical first and second persons, direct questions, and vocatives ('high-deixis'). We asked whether neural correlates of deixis obtained with fMRI would distinguish patients with and without frequent hallucinations (AVH + vs AVH-) from controls and each other. Results showed that high-deixis relative to low-deixis was associated with clusters of increased activation in the bilateral middle temporal gyri extending into the temporal poles and the inferior parietal cortex, in all groups. The AVH + and AVH- groups did not differ. When unifying them, the SZ group as a whole showed altered activity in the precuneus, midline regions and inferior parietal cortex. These results fail to confirm deictic processing anomalies specific to patients with AVH, but reveal such anomalies across SZ. Hypoactivation of this network may relate to a cognitive mechanism for attributing and anchoring thought and referential speech content in context.