Scalar implicature is not a default process: An ERP study of the scalar implicature processing under the effect of focus factor

Abstract

This study explored the processing mechanism of scalar implicatures under different focus conditions by the picture-sentence verification paradigm. Through the guidance of different types of incorrect sentences, scalar terms were controlled to adjust whether they were at the focus position and divided the focused and non-focused conditions. The behavioural results showed that when the content of the picture was “all squares have…”, more participants under the focused condition could judge that the underinformative sentence “some squares have…” was not appropriate. Moreover, according to whether participants could stably determine that the underinformative sentences were inappropriate, they were divided into pragmatic and semantic responders. The ERP results showed that pragmatic responders evoked a P200 effect, an N400 effect and a sustained negativity effect according to the scalar terms, and a P200 effect and a sustained positivity effect according to the sentence-final words. In contrast, semantic responders did not elicit any ERP effect. These results indicate that the generation of scalar implicatures is not completely determined by the scalar terms and that the focus factor plays an important role in the scalar implicatures inference.