Gray matter abnormalities in Major Depressive Disorder: a meta-analysis of voxel based morphometry studies.

Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Victoria, Australia.
Journal of affective disorders (Impact Factor: 3.76). 04/2011; 138(1-2):9-18. DOI: 10.1016/j.jad.2011.03.049
Source: PubMed

ABSTRACT Voxel-based morphometry (VBM) has been widely used to quantify structural brain changes associated with Major Depressive Disorder (MDD). While some consistent findings have been reported, individual studies have also varied with respect to the key brain regions affected by the illness, and how these abnormalities are related to patients' clinical characteristics. Here, we aimed to identify those brain regions that most consistently showed gray matter anomalies in MDD, and their clinical correlates, using meta-analytic techniques.
A systematic search of VBM studies was applied in MDD. Signed differential mapping, a new coordinate based neuroimaging meta-analysis technique, was applied to data collated from a total of 23 studies comparing regional gray matter volumes of 986 MDD patients and 937 healthy controls.
Gray matter was significantly reduced in a confined cluster located in the rostral anterior cingulate cortex (ACC). There were also gray matter reductions in dorsolateral and dorsomedial prefrontal cortex and decrease in the latter region was evident in patients with multiple-episodes. Amygdala and parahippocampal gray matter volumes were significantly reduced in studies including patients with comorbid anxiety disorders, as well as in first-episode/drug free samples.
Gray matter reduction in rostral ACC was the most consistent finding in VBM studies of MDD. The evidence for reductions in other regions within fronto-subcortical and limbic regions was less consistent. The associations between these gray matter anomalies and clinical characteristics, particularly measures relating to illness duration, suggest that chronic MDD has a robust and deleterious, albeit spatially focal, effect on brain structure.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, we review studies that have investigated brain morphology in chronic tinnitus in order to better understand the underlying pathophysiology of the disorder. Current consensus is that tinnitus is a disorder involving a distributed network of peripheral and central pathways in the nervous system. However, the precise mechanism remains elusive and it is unclear which structures are involved. Given that brain structure and function are highly related, identification of anatomical differences may shed light upon the mechanism of tinnitus generation and maintenance. We discuss anatomical changes in the auditory cortex, the limbic system, and prefrontal cortex, among others. Specifically, we discuss the gating mechanism of tinnitus and evaluate the evidence in support of the model from studies of brain anatomy. Although individual studies claim significant effects related to tinnitus, outcomes are divergent and even contradictory across studies. Moreover, results are often confounded by the presence of hearing loss. We conclude that, at present, the overall evidence for structural abnormalities specifically related to tinnitus is poor. As this area of research is expanding, we identify some key considerations for research design and propose strategies for future research.
    Neuroscience & Biobehavioral Reviews 05/2014; · 10.28 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A growing number of studies have used neuroimaging to further our understanding of how brain structure and function are altered in major depression. More recently, these techniques have begun to show promise for the diagnosis and treatment of depression, both as aids to conventional methods and as methods in their own right. In this review, we describe recent neuroimaging findings in the field that might aid diagnosis and improve treatment accuracy. Overall, major depression is associated with numerous structural and functional differences in neural systems involved in emotion processing and mood regulation. Furthermore, several studies have shown that the structure and function of these systems is changed by pharmacological and psychological treatments of the condition and that these changes in candidate brain regions might predict clinical response. More recently, "machine learning" methods have used neuroimaging data to categorize individual patients according to their diagnostic status and predict treatment response. Despite being mostly limited to group-level comparisons at present, with the introduction of new methods and more naturalistic studies, neuroimaging has the potential to become part of the clinical armamentarium and may improve diagnostic accuracy and inform treatment choice at the patient level.
    Neuropsychiatric Disease and Treatment 01/2014; 10:1509-22. · 2.00 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Most mental disorders involve disruptions of normal social behavior. Social neuroscience is an interdisciplinary field devoted to understanding the biological systems underlying social processes and behavior, and the influence of the social environment on biological processes, health and well-being. Research in this field has grown dramatically in recent years. Active areas of research include brain imaging studies in normal children and adults, animal models of social behavior, studies of stroke patients, imaging studies of psychiatric patients, and research on social determinants of peripheral neural, neuroendocrine and immunological processes. Although research in these areas is proceeding along largely independent trajectories, there is increasing evidence for connections across these trajectories. We focus here on the progress and potential of social neuroscience in psychiatry, including illustrative evidence for a rapid growth of neuroimaging and genetic studies of mental disorders. We also argue that neuroimaging and genetic research focused on specific component processes underlying social living is needed.
    World psychiatry: official journal of the World Psychiatric Association (WPA) 06/2014; 13(2):131-9. · 8.97 Impact Factor


Available from
Jun 2, 2014