Perceptual categorization of breath noises in speech pauses

Authors: Raphael Werner, Jürgen Trouvain, Beeke Muhlack, Bernd Möbius

Abstract:

This paper reports on two experiments that investigated how well listeners can discriminate between different types of breath noises. We used stimuli extracted from natural conversations and asked participants to assign them to one of six breath types (exhalations: oral, nasal; inhalations: oral, nasal, oral followed by nasal, nasal followed by oral). We further examined if phonetic knowledge, 2 seconds of speech context around the breath noises, and the breath type of the stimulus had an influence on the categorization. The results from Experiment 1 suggested an overall correct assessment rate of 74 %, a tendency for context to help with categorizing, and similar performance by phoneticians and lay people. Nasal inhalations were correctly categorized at very high rates, whereas oral exhalations seemed the most difficult. Experiment 2 further tested these findings and found an overall rate of 66 %. Nasal inhalations again stood out with very high rates, whereas nasal exhalations were lowest here. Although we matched the stimuli for context conditions, we found no significant effect for this factor. While there was a slight tendency for speech context to be beneficial, we found interactions of this factor with some breath types, such that for nasal inhalations and nasal followed by oral inhalations it was more helpful not to have the context.