Distributional and Acoustic Characteristics of Filler Particles in German with Consideration of Forensic-Phonetic Aspects

Abstract

In this study, we investigate the use of the filler particles (FPs) uh, um, hm, as well as glottal FPs and tongue clicks of 100 male native German speakers in a corpus of spontaneous speech. For this purpose, the frequency distribution, FP duration, duration of pauses surrounding FPs, voice quality of FPs, and their vowel quality are investigated in two conditions, namely, normal speech and Lombard speech. Speaker-specific patterns are investigated on the basis of twelve sample speakers. Our results show that tongue clicks and glottal FPs are as common as typically described FPs, and should be a part of disfluency research. Moreover, the frequency of uh, um, and hm decreases in the Lombard condition while the opposite is found for tongue clicks. Furthermore, along with the usual F1 increase, a considerable reduction in vowel space is found in the Lombard condition for the vowels in uh and um. A high degree of within- and between-speaker variation is found on the individual speaker level.