Linguistic threat activates the human amygdala

Studies in animals demonstrate a crucial role for the amygdala in emotional and social behavior, especially as related to fear and aggression. Whereas lesion and functional-imaging studies in humans indicate the amygdala's pa rticipation in assessing the significance of nonverbal as well as paralingu istic cues, direct evidence for its role in the emotional processing of lin guistic cues is lacking. In this study, we use a modified Stroop task along with a high-sensitivity neuroimaging technique to target the neural substr ate engaged specifically when processing linguistic threat. Healthy volunte er subjects were instructed to name the color of words of either threat or neutral valence, presented in different color fonts, while neural activity was measured by using (H2O)-O-15 positron-emission tomography, Bilateral am ygdalar activation was significantly greater during color naming of threat words than during color naming of neutral words. Associated activations wer e also noted in sensory-evaluative and motor-planning areas of the brain. T hus, our results demonstrate the amygdala's role in the processing of dange r elicited by language. In addition, the results reinforce the amygdala's r ole in the modulation of the perception of, and response to, emotionally sa lient stimuli. The current study further suggests conservation of phylogene tically older mechanisms of emotional evaluation in the context of more rec ently evolved linguistic function.