Semantic processing and emotional evaluation in the traffic sign understanding process: Evidence from an event-related potential study

Traffic signs are used on highways and in urban transportation facilities. As a critical element of driving safety, traffic signs are generally evaluated using questionnaires and by measuring reaction time. This study investigated the cognitive processing of traffic signs by measuring event-related potential (ERP) and explored semantic and emotional processing. A stimulus 1-stimulus 2 paradigm was adopted. Traffic sign-word pairs were organized into semantically congruent and semantically incongruent groups. Larger N400 amplitude and theta activity were simultaneously elicited by semantically incongruent traffic sign-word pairs, which indicated the semantic distance between traffic signs and words. A greater late positive potential was elicited by semantically congruent traffic sign-word pairs, which reflected participants' positive emotional arousal. Additionally, this study measured ERP to assess semantic distance and emotional arousal in the traffic sign understanding process.