Bio

Professional Education


  • Doctor of Philosophy, University of Michigan Ann Arbor (2009)

Stanford Advisors


Research & Scholarship

Current Research and Scholarly Interests


Corticosteroid impacts on neural correlates of emotion. My research focuses on harnessing what we learn from neuroimaging studies in psychiatric populations and from studying healthy people to improve and develop novel/add-on therapeutic techniques for the treatment of depression.

Publications

Journal Articles


  • The long-term impact of early adversity on late-life psychiatric disorders. Current psychiatry reports Gershon, A., Sudheimer, K., Tirouvanziam, R., Williams, L. M., O'Hara, R. 2013; 15 (4): 352-?

    Abstract

    Early adversity is a strong and enduring predictor of psychiatric disorders including mood disorders, anxiety disorders, substance abuse or dependence, and posttraumatic stress disorder. However, the mechanisms of this effect are not well understood. The purpose of this review is to summarize and integrate the current research knowledge pertaining to the long-term effects of early adversity on psychiatric disorders, particularly in late life. We explore definitional considerations including key dimensions of the experience such as type, severity, and timing of adversity relative to development. We then review the potential biological and environmental mediators and moderators of the relationships between early adversity and psychiatric disorders. We conclude with clinical implications, methodological challenges and suggestions for future research.

    View details for DOI 10.1007/s11920-013-0352-9

    View details for PubMedID 23443532

  • Exogenous Glucocorticoids Decrease Subgenual Cingulate Activity Evoked by Sadness NEUROPSYCHOPHARMACOLOGY Sudheimer, K. D., Abelson, J. L., Taylor, S. F., Martis, B., Welsh, R. C., Warner, C., Samet, M., Manduzzi, A., Liberzon, I. 2013; 38 (5): 826-845

    Abstract

    The glucocorticoid hormone cortisol is known to have wide-ranging effects on a variety of physiological systems, including the morphology and physiology of the amygdala and hippocampus. Disruptions of cortisol regulation and signaling are also linked with psychiatric disorders involving emotional disturbances. Although there is much evidence to suggest a relationship between cortisol signaling and the brain physiology underlying emotion, few studies have attempted to test for direct effects of cortisol on the neurophysiology of emotion. We administered exogenous synthetic cortisol (hydrocortisone, HCT) using two different dosing regimens (25 mg/day over 4 days, 100 mg single dose), in a double-blind placebo-controlled functional magnetic resonance imaging (fMRI) study. During fMRI scanning, healthy subjects viewed images designed to induce happy, sad, and neutral emotional states. Subjective emotional reactions were collected for each experimental stimulus after fMRI scanning. Mood ratings were also collected throughout the 4 days of the study. Both dose regimens of HCT resulted in decreased subgenual cingulate activation during sadness conditions. The 25 mg/day regimen also resulted in higher arousal ratings of sad stimuli. No effects of HCT were observed on any mood ratings. Few reliable effects of HCT were observed on brain activity patterns or subjective emotional responses to stimuli that were not sad. The inhibitory effects of cortisol on sadness-induced subgenual cingulate activity may have critical relevance to the pathophysiology of major depression, as both subgenual hyperactivity and decreased sensitivity to cortisol signaling have been documented in patients with depression.

    View details for DOI 10.1038/npp.2012.249

    View details for Web of Science ID 000316161300012

    View details for PubMedID 23303057

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