Allison C. Nugent

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Bipolar disorder (BD) has been associated with abnormalities of brain structure. Specifically, in vivo volumetric MRI and/or post mortem studies of BD have reported abnormalities of gray matter (GM) volume in the medial prefrontal cortex (PFC), amygdala, hippocampal subiculum and ventral striatum. These structures share anatomical connections with each(More)
CONTEXT While numerous magnetic resonance imaging (MRI) studies have evaluated adults with bipolar disorder (BPD), few have examined MRI changes in children with BPD. OBJECTIVE To determine volume alterations in children with BPD using voxel-based morphometry, an automated MRI analysis method with reduced susceptibility to various biases. A priori regions(More)
BACKGROUND Hippocampal volumes obtained from a group of medication-free, remitted subjects with recurrent major depressive disorder (MDD) were compared against corresponding measures from healthy controls. METHODS Thirty-one subjects with recurrent MDD in full remission, and 57 healthy controls underwent high resolution magnetic resonance imaging (MRI) on(More)
Previous neuromorphometric investigations of major depressive disorder (MDD) have reported abnormalities in gray matter in several regions, although the results have been inconsistent across studies. Some discrepancies in the results across studies may reflect design limitations such as small sample sizes, whereas others may reflect biological variability(More)
Multiple techniques exist for the automated segmentation of magnetic resonance images (MRIs). The validity of these techniques can be assessed by evaluating test-retest reliability, interscanner reliability, and consistency with manual segmentation. We evaluate these measures for the FSL/FIRST subcortical segmentation tool. We retrospectively analyzed 190(More)
BACKGROUND Evidence from neuroimaging post-mortem, and genetic studies suggests that bipolar disorder (BD) is associated with abnormalities of the serotonin-transporter (5-HTT) system. Because of various limitations of these studies, however, it has remained unclear whether 5-HTT binding is abnormal in unmedicated BD-subjects. This study used PET and(More)
The Enhancing NeuroImaging Genetics through Meta-Analysis (ENIGMA) Consortium is a collaborative network of researchers working together on a range of large-scale studies that integrate data from 70 institutions worldwide. Organized into Working Groups that tackle questions in neuroscience, genetics, and medicine, ENIGMA studies have analyzed neuroimaging(More)
CONTEXT Tryptophan depletion (TD) is a model used to study the contribution of reduced serotonin transmission to the pathogenesis of major depressive disorder (MDD). Recent studies have not sufficiently addressed the relative contribution of a functional-length triallelic polymorphism in the promoter of the serotonin transporter, 5-HTTLPR, to the behavioral(More)
OBJECTIVE Hippocampal volume is reduced in posttraumatic stress disorder (PTSD). In the present study, we sought to determine whether volume loss is homogenously distributed or confined to a certain part of the structure. METHOD Twenty-two adult outpatients with PTSD (11 after prolonged prepubertal trauma and 11 after single adult trauma) and 22 matched(More)
BACKGROUND Increased activity of the habenula has been implicated in the etiology of major depressive disorder (MDD), in which reductions in habenula volume are present after death. We conducted the first magnetic resonance imaging analysis of habenula volume in MDD and bipolar disorder (BD). METHODS High-resolution images (resolution approximately .4(More)