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PURPOSE: To evaluate the neurophenomenology of automatic writing (AW) in a spontaneous automatic writer (NN) and four high hypnotizables (HH). METHODS: During fMRI, NN and the HH were cued to perform spontaneous (NN) or induced (HH) AW, and a comparison task of copying complex symbols, and to rate their experience of control and agency. RESULTS: Compared to copying, for all participants AW was associated with less sense of control and agency and decreased BOLD signal responses in brain regions implicated in the sense of agency (left premotor cortex and insula, right premotor cortex, and supplemental motor area), and increased BOLD signal responses in the left and right temporoparietal junctions and the occipital lobes. During AW, the HH differed from NN in widespread BOLD decreases across the brain and increases in frontal and parietal regions. CONCLUSIONS: Spontaneous and induced AW had similar effects on agency, but only partly overlapping effects on cortical activity.
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Mapeamento Encefálico , Imageamento por Ressonância Magnética , Humanos , Encéfalo/diagnóstico por imagem , Lobo ParietalRESUMO
BACKGROUND: Magnetic Resonance Imaging (MRI) 2D phase-contrast flow measurement has been regarded as the gold standard in blood flow measurements and can be performed with free breathing or breath held techniques. We hypothesized that the accuracy of flow measurements obtained with segmented phase-contrast during breath holding, and in particular higher number of k-space segments, would be non-inferior compared to navigator phase-contrast. Volumes obtained from anatomic segmentation of cine MRI and Doppler echocardiography were used for additional reference. METHODS: Forty patients, five women and 35 men, mean age 65 years (range 53-80), were randomly selected and consented to the study. All underwent EKG-gated cardiac MRI including breath hold cine, navigator based free-breathing phase-contrast MRI and breath hold phase-contrast MRI using k-space segmentation factors 3 and 5, as well as transthoracic echocardiography within 2 days. RESULTS: In navigator based free-breathing phase-contrast flow, mean stroke volume and cardiac output were 79.7 ± 17.1 ml and 5071 ± 1192 ml/min, respectively. The duration of the acquisition was 50 ± 6 s. With k-space segmentation factor 3, the corresponding values were 77.7 ml ± 17.5 ml and 4979 ± 1211 ml/min (p = 0.15 vs navigator). The duration of the breath hold was 17 ± 2 s. K-space segmentation factor 5 gave mean stroke volume 77.9 ± 16.4 ml, cardiac output 5142 ± 1197 ml/min (p = 0.33 vs navigator), and breath hold time 11 ± 1 s. Anatomical segmentation of cine gave mean stroke volume and cardiac output 91.2 ± 20.8 ml and 5963 ± 1452 ml/min, respectively. Echocardiography was reliable in 20 of the 40 patients. The mean diameter of the left ventricular outflow tract was 20.7 ± 1.5 mm, stroke volume 78.3 ml ± 15.2 ml and cardiac output 5164 ± 1249 ml/min. CONCLUSIONS: In forty consecutive patients with coronary heart disease, breath holding and segmented k-space sampling techniques for phase-contrast flow produced stroke volumes and cardiac outputs similar to those obtained with free-breathing navigator based phase-contrast MRI, using less time. The values obtained agreed fairly well with Doppler echocardiography while there was a larger difference when compared with anatomical volume determinations using SSFP (steady state free precession) cine MRI.
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Técnicas de Imagem de Sincronização Cardíaca/métodos , Doença das Coronárias/fisiopatologia , Imagem Cinética por Ressonância Magnética/métodos , Técnicas de Imagem de Sincronização Respiratória/métodos , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Ecocardiografia , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Alterations of the sense of self induced by meditation include an increased sense of boundarylessness. In this study, we investigated behavioural and functional magnetic resonance imaging correlates of trait self-boundarylessness during resting state and the performance of two experimental tasks. We found that boundarylessness correlated with greater self-endorsement of words related to fluidity and with longer response times in a math task. Boundarylessness also correlated negatively with brain activity in the posterior cingulate cortex/precuneus during mind-wandering compared to a task targeting a minimal sense of self. Interestingly, boundarylessness showed quadratic relations to several measures. Participants reporting low or high boundarylessness, as compared to those in between, showed higher functional connectivity within the default mode network during rest, less brain activity in the medial prefrontal cortex during self-referential word processing, and less self-endorsement of words related to constancy. We relate these results to our previous findings of a quadratic relation between boundarylessness and the sense of perspectival ownership of experience. Additionally, an instruction to direct attention to the centre of experience elicited brain activation similar to that of meditation onset, including increases in anterior precentral gyrus and anterior insula and decreases in default mode network areas, for both non-meditators and experienced meditators.
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The abeyance of self-consciousness (SC) during hypnosis has been discussed as a central aspect of hypnosis, yet dispositional SC has been very rarely evaluated as a correlate of hypnotizability. In this study (N = 328), the authors administered the Harvard Group Scale of Hypnotic Susceptibility (HGSHS), the Inventory Scale of Hypnotic Depth (ISHD), and the Self-Consciousness Scale-Revised (SCS-R). Women tended to score higher than men on the HGSHS, besides experiencing greater ISHD automaticity. The Discontinuity (with everyday experiences) subscale of the ISHD correlated with the Public Self-Consciousness scale of the SCS-R and with the Private Self-Consciousness subscale (using simple, quadratic, and cubic regressions). Being concerned about the perception of others related to experiencing hypnosis as discontinuous with everyday life, which also related to being more introspective and interested in subjectivity at the middle range of scores. The article concludes with suggestions on how to pursue the implications of these results, including testing for nonlinear relations.
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Hipnose , Estado de Consciência , Feminino , Humanos , Hipnose/métodos , Hipnóticos e Sedativos , Masculino , Inventário de Personalidade , SugestãoRESUMO
AIM: To study patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) and describe different echocardiographic parameters and their change over time during almost 10 years follow-up period. METHODS: Fifteen patients (9 male, 6 female), aged 22-58 years (mean 40) with a diagnosis of ARVC, were followed up for a period of 6-10 years (mean 8.7). Twelve-lead and a signal- averaged ECG was recorded. Tricuspid and mitral annular motion and tissue Doppler imaging were registered by echocardiography. Wall motion score index (WMSI) was calculated for the left and right ventricles. RESULTS: We registered significant reduction in systolic tissue velocity on right ventricle free wall between the first and last investigations: 7-17 cm/s (mean 11.8) to 4-15 (mean 9.1), p=0.005. WMSI increased by at least 0.2 in 10/14 patients for the right and in 8/15 patients for the left ventricle. A decrease in velocity time integral for the left ventricular outflow was observed (16-30 to 13-21, p=0.009). CONCLUSION: ARVC is a progressive disease with individual variation. Left ventricular involvement may occur early in the disease. Tissue Doppler imaging is a useful tool to follow-up right ventricular abnormalities.
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Displasia Arritmogênica Ventricular Direita/diagnóstico por imagem , Ecocardiografia Doppler em Cores , Ecocardiografia Doppler de Pulso , Adulto , Displasia Arritmogênica Ventricular Direita/fisiopatologia , Progressão da Doença , Eletrocardiografia , Feminino , Seguimentos , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/diagnóstico por imagem , Fatores de Tempo , Valva Tricúspide/diagnóstico por imagem , Função Ventricular Esquerda , Função Ventricular DireitaRESUMO
BACKGROUND: Left ventricular size and function are important prognostic factors in heart disease. Their measurement is the most frequent reason for sending patients to the echo lab. These measurements have important implications for therapy but are sensitive to the skill of the operator. Earlier automated echo-based methods have not become widely used. The aim of our study was to evaluate an automatic echocardiographic method (with manual correction if needed) for determining left ventricular ejection fraction (LVEF) based on an active appearance model of the left ventricle (syngo AutoEF, Siemens Medical Solutions). Comparisons were made with manual planimetry (manual Simpson), visual assessment and automatically determined LVEF from quantitative myocardial gated single photon emission computed tomography (SPECT). METHODS: 60 consecutive patients referred for myocardial perfusion imaging (MPI) were included in the study. Two-dimensional echocardiography was performed within one hour of MPI at rest. Image quality did not constitute an exclusion criterion. Analysis was performed by five experienced observers and by two novices. RESULTS: LVEF (%), end-diastolic and end-systolic volume/BSA (ml/m2) were for uncorrected AutoEF 54 +/- 10, 51 +/- 16, 24 +/- 13, for corrected AutoEF 53 +/- 10, 53 +/- 18, 26 +/- 14, for manual Simpson 51 +/- 11, 56 +/- 20, 28 +/- 15, and for MPI 52 +/- 12, 67 +/- 26, 35 +/- 23. The required time for analysis was significantly different for all four echocardiographic methods and was for uncorrected AutoEF 79 +/- 5 s, for corrected AutoEF 159 +/- 46 s, for manual Simpson 177 +/- 66 s, and for visual assessment 33 +/- 14 s. Compared with the expert manual Simpson, limits of agreement for novice corrected AutoEF was lower than for novice manual Simpson (0.8 +/- 10.5 vs. -3.2 +/- 11.4 LVEF percentage points). Calculated for experts and with LVEF (%) categorized into < 30, 30-44, 45-54 and > or = 55, kappa measure of agreement was moderate (0.44-0.53) for all method comparisons (uncorrected AutoEF not evaluated). CONCLUSION: Corrected AutoEF reduces the variation in measurements compared with manual planimetry, without increasing the time required. The method seems especially suited for unexperienced readers.
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Doença da Artéria Coronariana/diagnóstico por imagem , Ecocardiografia/métodos , Endocárdio/diagnóstico por imagem , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Volume Sistólico , Disfunção Ventricular Esquerda/diagnóstico por imagem , Algoritmos , Inteligência Artificial , Doença da Artéria Coronariana/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Disfunção Ventricular Esquerda/etiologiaRESUMO
BACKGROUND: Left ventricular involvement in arrhythmogenic right ventricular cardiomyopathy (ARVC) is a common finding in autopsy studies. In clinical studies using myocardial scintigraphy, MRI and echocardiography, contradictory results have been reported. In this study, we therefore investigated a group of 15 patients with ARVC using thallium-201 (Tl) single-photon emission tomography (SPECT) and echocardiography including assessment of mitral annular motion with M-mode and pulsed tissue Doppler. METHODS: Exercise and rest Tl-201 SPECT were performed in 15 patients with ARVC. The time from diagnosis of the disease varied from less than 1-16 years. All patients fulfilled the established diagnostic criteria for ARVC. An echocardiographic examination, including assessment of left and right ventricular motion and measurements of the mitral annulus motion with M-mode and pulsed tissue Doppler was performed in the patients and in 25 normal subjects. RESULTS: Tl-201 uptake defects in the left ventricular myocardium were present in all except one patient (93%). The uptake defects were predominantly located to the anteroseptal and basal posterior segments. Wall motion abnormalities were seen in the same segments, and in addition to this, in the septal area. In line with this, the total amplitude and the peak systolic velocity of mitral annular motion at the septal point were significantly decreased in the patients compared with the control group. CONCLUSIONS: Our data show that left ventricular involvement is common in ARVC. Tl-201 SPECT and echocardiographic abnormalities were seen not only in patients with long-lasting symptoms but also in asymptomatic patients and in those with short duration of symptoms.