Introduction

Our current understanding of the representation of emotion in the human brain has been largely driven by research on nonhuman animals demonstrating that some brain regions seem to be specialized for emotion processing. One of the earliest findings of an “emotional” brain region was a study by Kluver and Bucy (1937) in which monkeys with large medial temporal lobe lesions displayed a range of odd emotional responses, such as approaching objects that are normally feared (e.g., snakes), orally exploring nonedible objects, and changes in sexual behavior, a constellation of social/emotional deficits termed “psychic blindness.” The original Kluver-Bucy lesion included a number of medial temporal lobe structures; however, Weiskrantz (1956) later isolated the amygdala as the critical structure whose lesion led to psychic blindness. Since that time, the amygdala has been considered a primary component of the neural circuits of emotion (Davidson & Irwin, 1999; LeDoux, 1996). Although there are several other brain structures that have been identified as important for normal emotional and social processing and responses (Papez, 1937; Damasio, 1999), early research in the cognitive neuroscience of emotion—often motivated by animal models—has emphasized the importance of the amygdala.

In this chapter, we review what has been learned about the human amygdala using functional imaging. We start with an assessment of functional imaging methods. We then proceed with a review of current research on the role of the human amygdala in emotional learning and memory, attention and perception, and social cognition.