Ten years ago, we reported that SM, a patient with rare bilateral amygdala damage, showed an intriguing impairment in her ability to recognize fear from facial expressions. Since then, the importance of the amygdala in processing information about facial emotions has been borne out by a number of lesion and functional imaging studies. Yet the mechanism by which amygdala damage compromises fear recognition has not been identified. Returning to patient SM, we now show that her impairment stems from an inability to make normal use of information from the eye region of faces when judging emotions, a defect we trace to a lack of spontaneous fixations on the eyes during free viewing of faces. Although SM fails to look normally at the eye region in all facial expressions, her selective impairment in recognizing fear is explained by the fact that the eyes are the most important feature for identifying this emotion. Notably, SM's recognition of fearful faces became entirely normal when she was instructed explicitly to look at the eyes. This finding provides a mechanism to explain the amygdala's role in fear recognition, and points to new approaches for the possible rehabilitation of patients with defective emotion perception.

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Long-term memories are influenced by the emotion experienced during learning as well as by the emotion experienced during memory retrieval. The present article reviews the literature addressing the effects of emotion on retrieval, focusing on the cognitive and neurological mechanisms that have been revealed. The reviewed research suggests that the amygdala, in combination with the hippocampus and prefrontal cortex, plays an important role in the retrieval of memories for emotional events. The neural regions necessary for online emotional processing also influence emotional memory retrieval, perhaps through the reexperience of emotion during the retrieval process. Keywords emotion; memory; retrieval; amygdala; prefrontal cortex Retrieval of Emotional MemoriesMemories of our experiences are likely characterized by representations in the form of neuronal activity. Activity among a network of neurons represents a code for the experience of, say, a birthday party. When this network is activated by some cue that triggers a reexperience of that event, we are said to have recollected the birthday party. Emotional events are often remembered with greater accuracy and vividness (though these two characteristics do not always go together) than events lacking an emotional component (Reisberg & Hertel, 2005). This enhanced memory for emotional events has been attributed to interactions between the amygdala and other neural areas such as the hippocampus and prefrontal cortex (PFC) (Cahill & McGaugh, 1996). The amygdala is active during emotional situations, and this activity influences the encoding and consolidation of the memory trace for the emotional event (see LaBar & Cabeza, 2006;Phelps, 2004, for a review). These effects on the "front end" of memory (attention, encoding, the early stages of consolidation) have been well documented, but the influence of emotion and amygdala activity on memory retrieval has been more difficult to demonstrate. This difficulty is partly due to the fact that, by definition, an emotional event exerts its influence during the initial experience of the event. Understanding the influence of emotion on retrieval mechanisms could have utility in treating disorders of emotion and memory such as depression and posttraumatic stress disorder (PTSD; Davis & Whalen, 2001;Elzinga & Bremner, 2002), in which emotion may influence all phases of memory. Given that it is at the retrieval stage that the pathological effects of negative emotion are most often observed (Elzinga & Bremner, 2002;Williams & Scott, 1988), perhaps this is also where treatment may work most effectively. Recent work on the neurobiology of retrieval, extinction learning, and potential treatments for psychopathology highlight the broad influence that emotion exerts on memory retrieval mechanisms. In this review, I examine this influence and discuss the applications of this work across many areas of psychology.Correspondence concerning this article should be addressed to Tony W. Buchanan, who is now at the Department of Psychology...

In this study, we evaluated cardiovascular, neuroendocrine, and psychological adjustment to repeated presentations of a public speaking and a mental arithmetic task. Brief versions of mental arithmetic tasks have been used widely in previous reactivity studies, and growing attention to more socially salient tasks has led to the increased use of public speaking tasks. However, psychophysiological adjustment during extended and repeated exposure to these tasks has not been delineated. In the present study, 52 healthy men worked on three 8-min presentations of public speaking and of mental arithmetic in a repeated measure design. Both tasks produced substantial cardiovascular, adrenocorticotropic hormone, and cortisol responses; public speaking produced greater changes. Repeated presentations of public speaking produced a stable pattern of cardiac activation, whereas repetitions of the mental arithmetic initially produced large cardiac responses that changed to a more vascular tonus across task periods. Both tasks increased negative moods. However, correlations between the endocrine, cardiovascular, and negative moods were significant only during the public speaking stressor. The public speaking task is a socially relevant experimental protocol for studying reactivity in the laboratory setting and elicits relatively high, stable, and homogeneous responses.

Emotion has been shown to have a modulatory effect on declarative memory. Normal aging is associated with a decline in declarative memory, but whether aging might affect the influence of emotion on memory has not been established. To investigate this, we administered a task that provides a detailed assessment of emotional memory to 80 neurologically normal adults ranging in age from 35 to 85 years. Across ages, memory performance was found to be modulated by the emotional significance of stimuli in a comparable manner (improved memory for gist, compromised memory for visual detail), despite an overall decline in memory performance with increasing age. The results raise the interesting possibility that aging has a differential effect on hippocampal versus amygdala function.