Prediction of semantic features is modulated by global prediction reliability: Evidence from the N400 effect

Lexical predictability has been shown to be modulated by the global context, but it is unclear whether the global context has a similar modulating effect on the prediction of semantic features. Event-related potentials (ERP) should be helpful in addressing this question, as the N400 effect is sensitive to both lexical predictability and the prediction of semantic features during sentence comprehension. The present study manipulated the semantic similarity between unpredictable target words and expected words in experimental sentences. Different types of filler sentences (predictable vs. incongruous) were used to manipulate the global prediction reliability (GPR). The ERP results showed that, in the predictable filler block, the N400 was reduced when there was high semantic similarity between the unpredictable target word and expected word in the experimental sentences. However, this association was absent in the incongruous filler block, in which participants were discouraged from predicting the upcoming information. These results suggest that the prediction of semantic features of upcoming words could be modulated by the global context.