Unknown word detection based on event-related brain desynchronization responses

Abstract

The appearance of unknown words often disturbs communication. Most work on unknown words in spoken dialog systems deals with words that are uttered by the user, but which are not covered by the system's vocabulary. In this paper, we focus on detecting unknown words from the user side, in the case where the system utterance is unknown to the user. In particular, we develop a classifier based on Electroencephalography (EEG) signal from the user's brain waves, including the use of absolute power and Event-Related Desynchronization (ERD) features. The results show that we could detect the characteristics of brain waves at the time of unknown word perception significantly better than the chance rate.