摘要：

Evidence from both experimental animal and clinical studies indicates that emotional behavior is critically dependent on the amygdala. In this chapter we suggest that the amygdala serves as a target for converging inputs from a wide array of cortical processing areas in all the sensory modalities. This sensory convergence, which is regarded as an important antecedent to the encoding of the emotional significance of a sensory event, is facilitated by intrinsic amygdaloid connections. An examination of these connections in the monkey reveals a dense, highly organized pattern of projections coursing from the nuclei that receive the bulk of the sensory inputs to the nuclei that project outward to the hypothalamus and midbrain. In this way, sensory information reaching the amygdala can be further integrated before it is relayed to deeper regions for the generation and expression of emotions. The anatomical evidence thus strongly reinforces the view derived from neurobehavioral studies that the striking lack of emotional behavior following amygdalectomy is the consequence of a disconnection of cortically processed sensory information from affective mechanisms centered in the hypothalamus and midbrain. Some major questions that remain unanswered are whether the amygdala is important for the sensory arousal of all classes of emotion, whether the reinforcement properties of stimuli may be partially dissociable from their emotion-arousing properties, and whether the amygdala may mediate not only the sensory arousal of emotion but also a reciprocal influence of emotion upon the processing and, perhaps also, the storage of sensory events.

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