Sophie Schwartz¹, Le Wang², Barbara Shinn-Cunningham³
¹Boston University, ²Boston University, ³Boston University
Whether a spoken phrase is interpreted as a question or a statement is often cued solely by a transient tonal rise or fall in its terminating word. The goal of this study was to investigate an early auditory response to pitch contours that typically distinguish questions from declarative statements in our everyday speech. In experiment 1, subjects passively listened to an oddball stream of declarative and interrogative sentences. The standard sentence (81% of trials) and the deviant sentence (19% of trials) only differed in the pitch of the last word, naturally falling for the statement and rising for the question. The same passive oddball paradigm was used in experiment 2 and 3, but real speech was replaced by pitch-matched four-tone sequences composed of pure or harmonic complex tones. Based on preliminary results, neither interrogative deviants nor declarative deviants elicited an MMN (mismatch negativity) response in the speech condition. However, interrogative deviants did produce an MMN response in the pure tone and complex tone conditions. These results are consistent with prior work demonstrating an MMN response to deviations in pure tone streams designed to mimic question-statement pitch contours (Leitman et al. 2009). The present findings demonstrate the utility of passive EEG paradigm for assessing preattentive auditory processing of pitch contour. Such results may prove useful for assessing atypical perception of prosodic contours in those with receptive language impairments.
Keywords: ERP, MMN, Speech, Prosody