In the CEED Lab, we are currently pursuing several interrelated lines of investigation to gain a better understanding of the role that cognitive processes and stress reactivity play in major depressive disorder (MDD) and social anxiety disorder (SAD). These include studies of biased processing of emotional stimuli (e.g., interpretation, memory, etc.) and mechanisms underlying such biases, stress reactivity, and emotion regulation. In pursuit of these lines of research, we employ computerized cognitive tasks as well as neuroendocrine and psychophysiological measures (e.g., cortisol, EMG, HRV).
Processing of Facial Expressions
It is well documented that both MDD and SAD are associated with interpersonal difficulties. Given the importance of accurately processing facial expressions in successful social interactions, one source of difficulties in MDD/SAD may be problems in processing the emotional facial expressions of other people. Using a series of innovative experimental paradigms, we are investigating biased processing of facial expressions, neutral faces in particular, in individuals with MDD and/or SAD.
Comorbidity between MDD and SAD
Although comorbidity is the norm rather than exception, researchers have largely ignored the issues of comorbidity until recently. As a result, not much is known about comorbidity. Yes, we know that SAD and MDD highly are comorbid and share many common characteristics. We also know that those with comorbid MDD and SAD fare less well than those with "pure" MDD or SAD in terms of treatment outcome. Unfortunately, that's about as much as we know about comorbid MDD and SAD. In the CEED Lab, we are examining how individuals with comorbid MDD and SAD are similar to and different from individuals with either forms of "pure" disorder. This line of research includes studies of working memory capacity and cortisol stress reactivity.
Cortisol Stress Reactivity and Heart Rate Variability in MDD and SAD
Most people feel anxious or sad when they experience negative life events. Interestingly, however, even people who experience high levels of stress do not necessarily develop emotional disorders. It has become evident that how individuals regulate negative affect elicited by stressful events is crucial in understanding anxiety and depression. We are investigating the effects of rumination/post-event processing on individuals' cortisol stress reactivity and recovery. Concurrently, we are also examining the effects of rumination on heart rate variability during and after a stressor.