Cognitive and emotional conflicts of counter-conformity choice in purchasing books online: an event-related potentials study.

Using event-related potentials (ERPs), this study investigated the neural substrates of the conflicts in counter-conformity choices in purchasing books online. For each trial, a participant decided whether to buy a book according to the title keyword, as well as the numbers of positive and negative reviews on the book. A participant's choice was termed conformity if she/he decided to buy the book under the condition of consistently positive reviews, or not to buy the book under the condition of consistently negative reviews, whereas the case was counter-conformity if a participant did the opposite. In the time window 300-600ms after the stimulus onset, a strong negative deflection of ERP (N500) was recorded when participants made counter-conformity choices. The topographic distribution of the N500 (N400-like) is not typical of the semantic N400. The N500 might be evoked by the cognitive and emotional conflicts faced by participants in counter-conformity choices. The present findings provide evidence that the N400 can be elicited by non-semantic conflicts.