amígdala

amügdala, commonly known as the amygdala in English, refers to a pair of almond-shaped nuclei located in the medial temporal lobe. It is a core component of the limbic system and plays a central role in processing emotions, especially those related to danger and threat. The amügdala consists of several subnuclei organized into functional groups, including basolateral, basomedial, and centromedial complexes, distributed within each hemisphere. It sits near the hippocampus and is connected to widespread cortical and subcortical areas.

The amügdala receives sensory information from multiple pathways, including thalamic and cortical routes, and integrates this data to assess emotional salience. It projects to the prefrontal cortex, insula, hippocampus, hypothalamus, brainstem, and nucleus accumbens, enabling rapid autonomic, hormonal, and behavioral responses. Functions attributed to the amügdala include fear conditioning, emotional learning, threat assessment, and modulation of memory consolidation for emotionally charged events. It also influences social behavior, decision making, and the experience of emotions beyond fear.

Clinical and research relevance follows from its role in emotion regulation. Bilateral amügdala damage or dysfunction can blunt fear responses and alter social and emotional behavior, as seen in certain patients and experimental models. The amügdala is also implicated in anxiety disorders, post-traumatic stress disorder, and some forms of epilepsy. Across mammals, the amügdala is a conserved structure contributing to adaptive behavioral responses to emotionally salient stimuli.