Is conceptual processing in music automatic? An electrophysiological approach

Recent evidence suggests that music perception, much alike language perception, involves the cognitive processing of concepts, that is abstract general ideas. In a previous study (Daltrozzo and Schön, Conceptual processing in music as revealed by N400 effects on words and musical targets. Journal of Cognitive Neuroscience, In Press), we reported the effect of the presentation of a musical excerpt (the context) on the perception of a word, while participants judged the conceptual relatedness between the two stimuli. Event-Related Potentials (ERPs) showed a N400 effect: a larger N400 to words judged unrelated to their context compared to related words. In the present experiment, we decided to test the influence of the relatedness task on the N400 effect by using a more implicit task: lexical decision. We recorded behavioral and ERP data while participants were presented 50 related and 50 unrelated pairs (excerpt context/word target). An N400 effect was again observed. However, the N400 effect found with a lexical decision was more than two times smaller than with a relatedness judgment task and was significant in a later latency range: 500 to 650 ms instead of 300 to 550 ms with a relatedness judgment. These differences are interpreted as reflecting the task-induced modulation of explicit (strategic) mechanisms involved in the N400 effect.