The Neural Systems that Respond to Emotional Stimuli with Phylogenetic and Ontogenetic Significance

Abstract

Neural and behavioral responses to emotional stimuli often are discussed within an evolutionary framework. Although some of the information that elicits an emotional response is likely to have had evolutionary significance (e.g., snakes, spiders), many other stimuli would not have been evolutionarily relevant (e.g., guns, grenades). The present study re-analyzed data from two fMRI studies (Kensinger et al., 2007; Kensinger & Schacter, 2008) to examine whether the neural systems that respond to emotional stimuli differ depending upon whether those stimuli were of phylogenetic or ontogenetic significance. The results revealed that when stimuli were ontogenetic, activity was increased in regions of the anterior cingulate and orbitofrontal cortices. By contrast, when stimuli were phylogenetic, activity was increased in a region spanning the lingual and fusiform gyri. These results suggest that there can be differences in how emotional stimuli are processed, and those differences can depend upon the stimuli’s evolutionary significance.