Stress Response to the Functional Magnetic Resonance Imaging Environment in Healthy Adults Relates to the Degree of Limbic Reactivity during Emotion Processing

Background: Imaging techniques are increasingly being used to examine the neural correlates of stress and emotion processing; however, relations between the primary stress hormone cortisol, the functional magnetic resonance imaging (fMRI) environment, and individual differences in response to emotional challenges are not yet well studied. The present study investigated whether cortisol activity prior to, and during, an fMRI scan may be related to neural processing of emotional information. Methods: Twenty-six healthy individuals (10 female) completed a facial emotion perception test during 3-tesla fMRI. Results: Prescan cortisol was significantly correlated with enhanced amygdala, hippocampal, and subgenual cingulate reactivity for facial recognition. Cortisol change from pre- to postscanning predicted a greater activation in the precuneus for both fearful and angry faces. A negative relationship between overall face accuracy and activation in limbic regions was observed. Conclusion: Individual differences in response to the fMRI environment might lead to a greater heterogeneity of brain activation in control samples, decreasing the power to detect differences between clinical and comparison groups.