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Alzheimer's disease (AD) and antecedent factors associated with AD were explored using amyloid imaging and unbiased measures of longitudinal atrophy in combination with reanalysis of previous metabolic and functional studies. In total, data from 764 participants were compared across five in vivo imaging methods. Convergence of effects was seen in posterior(More)
BACKGROUND The amygdala has a central role in processing emotions, particularly fear. During functional magnetic resonance imaging (fMRI) amygdala activation has been demonstrated outside of conscious awareness using masked emotional faces. METHODS We applied the masked faces paradigm to patients with major depression (n = 11) and matched control subjects(More)
To better understand intrinsic brain connections in major depression, we used a neuroimaging technique that measures resting state functional connectivity using functional MRI (fMRI). Three different brain networks--the cognitive control network, default mode network, and affective network--were investigated. Compared with controls, in depressed subjects(More)
The recently discovered default mode network (DMN) is a group of areas in the human brain characterized, collectively, by functions of a self-referential nature. In normal individuals, activity in the DMN is reduced during nonself-referential goal-directed tasks, in keeping with the folk-psychological notion of losing one's self in one's work. Imaging and(More)
BACKGROUND Important functional connections within the default mode network (DMN) are disrupted in Alzheimer's disease (AD), likely from amyloid-beta (Abeta) plaque-associated neuronal toxicity. Here, we sought to determine if pathological effects of Abeta amyloid plaques could be seen, even in the absence of a task, by examining functional connectivity in(More)
This study takes advantage of continuing advances in the precision of magnetic resonance imaging (MRI) to quantify hippocampal volumes in a series of human subjects with a history of depression compared with controls. We sought to test the hypothesis that both age and duration of past depression would be inversely and independently correlated with(More)
PURPOSE To test automated three-dimensional magnetic resonance (MR) imaging morphometry of the human hippocampus, to determine the potential gain in precision compared with conventional manual morphometry. MATERIAL AND METHODS A canonical three-dimensional MR image atlas was used as a deformable template and automatically matched to three-dimensional MR(More)
Hippocampal volumes of subjects with a history of major depressive episodes but currently in remission and with no known medical comorbidity were compared to matched normal controls by using volumetric magnetic resonance images. Subjects with a history of major depression had significantly smaller left and right hippocampal volumes with no differences in(More)
BACKGROUND Beta-amyloid (Abeta) plaques are the hallmark of Alzheimer disease (AD). A PET imaging tracer that binds to Abeta plaques in vivo, N-methyl-[(11)C]2-(4'-methylaminophenyl)-6-hydroxybenzothiazole (or [(11)C]PIB for "Pittsburgh Compound-B"), has significantly higher binding in subjects diagnosed with dementia of the Alzheimer type (DAT) compared to(More)
We recently reported that fluoxetine or paroxetine, two selective serotonin reuptake inhibitors (SSRIs), when administered to rats, increase the brain content of the neurosteroid 3alpha-hydroxy-5alpha-pregnane-20-one (3alpha5alpha-ALLO) without altering the brain content of other neurosteroids. ALLO (3alpha5alpha and 3alpha5beta isomers) binds with high(More)