Major depressive disorder (MDD) is characterized by a dysregulated fronto-limbic network. The hyperactivation of limbic regions leads to increased attention and processing of emotional information, with a bias toward negative stimuli. Pathological ruminative behavior is a common symptom of depressive disorder whereby the individual is unable to disengage from internal mental processing of emotionally salient events. In fact, lower deactivations of the neural baseline resting state may account for the increased internal self-focus. The insular cortex, with its extensive connections to fronto-limbic and association areas has recently also been implicated to be a part of this network. Given its wide-reaching connectivity, it has been putatively implicated as an integration center of autonomic, visceromotor, emotional, and interoceptive information. The following paper will review recent imaging findings of altered insular function and connectivity in depressive pathology.
Keywords: insula, fMRI, depression, interoception, awareness, stress, DMN, neuroplasticity
Citation: Sliz D and Hayley S (2012) Major depressive disorder and alterations in insular cortical activity: a review of current functional magnetic imaging research. Front. Hum. Neurosci. 6:323. doi: 10.3389/fnhum.2012.00323
Received: 09 July 2012; Accepted: 12 November 2012;
Published online: 03 December 2012.
Edited by:John J. Foxe, Albert Einstein College of Medicine, USA
Reviewed by:Christopher Marano, Johns Hopkins University School of Medicine, USA
Copyright: © 2012 Sliz and Hayley. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in other forums, provided the original authors and source are credited and subject to any copyright notices concerning any third-party graphics etc.
*Correspondence: Shawn Hayley, Department of Neuroscience, Carleton University, 327 Life Sciences Research Building, 1125 Colonel By Drive, Ottawa, ON, Canada K1S 5B6. e-mail: firstname.lastname@example.org