Perceived Communicative Context and Emotional Content Amplify Visual Word Processing in the Fusiform Gyrus

摘要

The personal significance of a language statement depends on its communicative context. However, this is rarely taken into account in neuroscience studies. Here, we investigate how the implied source of single word statements alters their cortical processing. Participants' brain event-related potentials were recorded in response to identical word streams consisting of positive, negative, and neutral trait adjectives stated to either represent personal trait feedback from a human or to be randomly generated by a computer. Results showed a strong impact of perceived sender. Regardless of content, the notion of receiving feedback from a human enhanced all components, starting with the P2 and encompassing early posterior negativity (EPN), P3, and the late positive potential (LPP). Moreover, negative feedback by the "human sender" elicited a larger EPN, whereas positive feedback generally induced a larger LPP. Source estimations revealed differences between "senders" in visual areas, particularly the bilateral fusiform gyri. Likewise, emotional content enhanced activity in these areas. These results specify how even implied sender identity changes the processing of single words in seemingly realistic communicative settings, amplifying their processing in the visual brain. This suggests that the concept of motivated attention extends from stimulus significance to simultaneous appraisal of contextual relevance. Finally, consistent with distinct stages of emotional processing, at least in contexts perceived as social, humans are initially alerted to negative content, but later process what is perceived as positive feedback more intensely.