NEUROIMAGING OF EMOTION 1 The Neuroimaging of Emotion

Questions about the nature of emotion have existed since psychology emerged as a scientific discipline in the late nineteenth century (Darwin, 1898; Dewey, 1895; Irons, 1897; James, 1884). For a century, scientists were unable to measure emotions at their source, and so relied on measures of behavior, reported experience, and activity of the peripheral nervous system to address fundamental questions about what emotions are and how they function in the economy of the mind. While much has been learned that is of both scientific interest and practical value, questions about the nature of emotion remained fundamentally unresolved. The relatively recent introduction of neuroimaging techniques, particularly functional magnetic resonance imaging (fMRI) and positron emission tomography (PET), provide a new perspective on the emotion in the intact human brain, and have the potential to identify which brain areas are consistently and specifically associated with particular types of emotional states. Fifteen years of neuroimaging research has investigated the neural underpinnings of emotions including responses to basic affective stimuli such as pictures or odors, the experience and regulation of the discrete emotional events that we refer to as disgust, anger, and desire, and the perception of emotion in others. These finding