Rodent studies suggest the existence of a subcortical pathway that rapidly processes threat-related information, but direct evidence for such a pathway in primates has been lacking. Here, people with epilepsy who had been implanted with intracranial electrodes in the amygdala and, in some cases, in the visual cortex were shown pictures of faces. Fearful faces elicited activity in the amygdala, which is implicated in threat processing, more quickly than in the visual cortex, indicating that a rapid threat-processing pathway exists in humans.