We examined the reproducibility of DCM in healthy subjects (young 18-48 years, n = 27; old 50-80 years, n = 15) in the context of action selection. We then examined the effects of Parkinson’s disease (50-78 years, Hoehn and Yahr stage 1-2.5, n = 16) and dopaminergic therapy. Forty-eight models were compared, for each of 90 sessions from 58 subjects. Model-evidences clustered

according to sets of structurally similar models, with high correlations over two sessions in healthy older subjects. The same model was identified as most likely in healthy controls on both sessions and in medicated patients. In this most likely network model, the selection of action was associated with enhanced coupling between prefrontal cortex and the pre-supplementary motor area. However, the parameters for Trichostatin A order intrinsic connectivity and contextual modulation in this model were poorly correlated across sessions. A different model was identified in patients with Parkinson’s disease after medication withdrawal. In “off” patients, action selection was associated with enhanced connectivity from prefrontal to lateral premotor cortex. This accords with independent evidence of a dopamine-dependent Selleck BI2536 functional disconnection of the SMA in Parkinson’s disease. Together, these results suggest that DCM model selection is robust and sensitive enough

to study clinical populations and their pharmacological treatment. For critical inferences, Cl-amidine price model selection may be sufficient. However, caution is required when comparing groups or drug effects in terms of the connectivity parameter estimates, if there are significant posterior covariances among parameters. (C) 2009 Elsevier Inc. All rights reserved.”
“Background: Late-life depression encompasses both patients with late-life onset of depression ( bigger than 60

years) and older adults with a prior and current history of depression. The aim of the study was to analyze the impact of the economic condition and family relations in childhood as risk factors for late-life depression. Subjects and methods: This was an analytical cross-sectional study comprising 120 subjects, 60 patients with unipolar depression and 60 subjects without depressive disorders, diagnosed in accordance with the 10-th International Classification of Mental and Behavioural Disorders. All participants in the study were above the age of 60 and there was no significant statistical difference in the sex proportion in both groups (p bigger than 0.05). Data for the examination were taken from a self-reported questionnaire designed for our aim. The Geriatric Depression Scale was used to measure depressive symptoms. Results: Our results have shown that severe financial difficulties are important events in childhood and are risk factors for depression in the elderly (Chi-square=12.68, df=2, p=0.0018). Our investigation has found the association of family relations with late-life depression.