Reduced right ventrolateral prefrontal cortex activity while inhibiting positive affect is associated with improvement in hedonic capacity after 8 weeks of antidepressant treatment in major depressive disorder
Sharee N Light, Aaron S Heller, Tom Johnstone, Gregory G Kolden, Michael J Peterson, Ned H Kalin, Richard J Davidson, Sharee N Light, Aaron S Heller, Tom Johnstone, Gregory G Kolden, Michael J Peterson, Ned H Kalin, Richard J Davidson
Abstract
Background: Anhedonia, a reduced ability to experience pleasure, is a chief symptom of major depressive disorder and is related to reduced frontostriatal connectivity when attempting to upregulate positive emotion. The present study examined another facet of positive emotion regulation associated with anhedonia-namely, the downregulation of positive affect-and its relation to prefrontal cortex (PFC) activity.
Methods: Neuroimaging data were collected from 27 individuals meeting criteria for major depressive disorder as they attempted to suppress positive emotion during a positive emotion regulation task. Their PFC activation pattern was compared with the PFC activation pattern exhibited by 19 healthy control subjects during the same task. Anhedonia scores were collected at three time points: at baseline (time 1), 8 weeks after time 1 (i.e., time 2), and 6 months after time 1 (i.e., time 3). Prefrontal cortex activity at time 1 was used to predict change in anhedonia over time. Analyses were conducted utilizing hierarchical linear modeling software.
Results: Depressed individuals who could not inhibit positive emotion-evinced by reduced right ventrolateral prefrontal cortex activity during attempts to dampen their experience of positive emotion in response to positive visual stimuli-exhibited a steeper anhedonia reduction slope between baseline and 8 weeks of treatment with antidepressant medication (p < .05). Control subjects showed a similar trend between baseline and time 3.
Conclusions: To reduce anhedonia, it may be necessary to teach individuals how to counteract the functioning of an overactive pleasure-dampening prefrontal inhibitory system.
Trial registration: ClinicalTrials.gov NCT00909155.
Conflict of interest statement
Financial Disclosures: Sharee N. Light, Aaron S. Heller, Tom Johnstone, Michael J. Peterson, Gregory G. Kolden and Richard J. Davidson reported no biomedical financial interests or potential conflicts of interest. Dr. Ned H. Kalin is a consultant related to the development of psychotropic agents (or serves on the Scientific Advisory Board) for the following companies: Astra Zeneca, Bristol-Myers-Squibb, CeNeRx Biopharma, Corcept, Cyberonics, Forest Laboratories, General Electric Corp., Jazz Pharmaceuticals, Eli Lilly, Neuronetics, Sanofi Syntholabs, and Wyeth Pharmaceuticals. Wyeth Pharmaceuticals funded this study. Dr. Ned H. Kalin has stock options in Corcept and CeNeRx and is principal owner of Promoter Neurosciences.
Copyright © 2011 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
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Source: PubMed