Acoustic characteristics of belching in speech

Abstract

“When such nonspeech sounds occur connected in speech they sometimes carry important social connotations (Pike, 1943: 39).” This sentiment is attested over and over again in linguistic literature that provides cases of nontraditional sounds (such as coughing, moans, cries) being co-opted into the continuous stream of speech within discourse (Ohala,1995; Ogden, 2013; Prelock and Hutchins, 2018; Pinto and Vigil, 2018). This reveals an unanswered problem: While many of these sounds have been able to be expressed by their phonetic parameters in paralinguistics (Trager, 1958; Poyatos, 1975), belching—as evident from a case study as being intentionally interjected into the speech stream with social connotations (Kidner, 2018)—has consistently eluded detailed description using acoustic parameters. Acoustic data were taken from this case study, and belching was distinguished in Praat (Boersma and Weenik, 2018) from modal speech by an increase in glottal pulses and jitter (>4.4%), an increase in shimmer (>15%), low pitch (≤300 Hz), and an irregular amplitude contour. These criteria for belch identification (while not exhaustive) allow us not just to classify belches phonetically within the corpus, but moves the process of acoustically defining otherwise difficult paralinguistic sounds forward.