Comparison of event-related potentials between conceptually similar Chinese words and pictures

The purpose of this study was to examine the effects of conceptual similarity between target and nontarget stimuli on P300 component during a multistimulus oddball paradigm. P300 is an endogenous component of event related potentials, which can reflect the information processing of brain. It is elicited in two-stimulus oddball task in this report. The stimuli were pictures of three objects and their corresponding Chinese words and English words. Participants were required to keep a mental count of number of target presentations. In experiment 1, the target was the picture "bag", the Chinese word was considered to be the related nontarget, others were nontarget, the target elicited a large p300, the related nontarget stimulus and nontarget failed to elicit a p300. In experiment 2, the target was the Chinese word of bag, the picture was considered to the related nontarget, others were nontarget. Both the word target and the nontarget picture elicited large p300s, though the p300 to the related nontarget was smaller in amplitude. In this work, the experiments elucidate that imagery and verbal information are processed by distinct but interconnected systems.