Speaking Clearly for the Hard of Hearing II

Abstract

The first paper of this series (Picheny, Durlach, & Braida, 1985) presented evidence that there are substantial intelligibility differences for hearing-impaired listeners between nonsense sentences spoken in a conversational manner and spoken with the effort to produce clear speech. In this paper, we report the results of acoustic analyses performed on the conversational and clear speech. Among these results are the following. First, speaking rate decreases substantially in clear speech. This decrease is achieved both by inserting pauses between words and by lengthening the durations of individual speech sounds. Second, there are differences between the two speaking modes in the numbers and types of phonological phenomena observed. In conversational speech, vowels are modified or reduced, and word-final stop bursts are often not released. In clear speech, vowels are modified to a lesser extent, and stop bursts, as well as essentially all word-final consonants, are released. Third, the RMS intensities for obstruent sounds, particularly stop consonants, is greater in clear speech than in conversational speech. Finally, changes in the long-term spectrum are small. Thus, speaking clearly cannot be regarded as equivalent to the application of high-frequency emphasis.

Dynamically adapted context-specific hyper-articulation: Feedback from interlocutors affects speakers’ subsequent pronunciations

“…A related question focuses on the relation between adaptive changes to production in a specific environment (such as the present experiment) and speech registers, such as clear speech, infant-, and foreigner-directed speech (e.g., Kuhl et al, 1997; Picheny et al, 1986; Uther et al, 2007). …”

“…For example, speech directed at adults differs systematically from speech directed at infants (e.g., Kuhl et al, 1997; Pate & Goldwater, 2015) or pets (e.g., Burnham, Kitamura, & Vollmer-Conna, 2002). Similarly, speech directed at typical adult native interlocutors differs from speech directed at non-native interlocutors (e.g., Uther, Knoll, & Burnham, 2007) or audiences with impaired comprehension (e.g., “clear speech”, speech directed at the hard of hearing, Picheny, Durlach, & Braida, 1986). …”

On the -oo Suffix of Campbell’s Monkeys

“…In human communication more generally, the phonetic properties of speech have been shown to vary with respect to communicational and situational demands (Picheny, Durlach, and Braida 1986). Lindblom (1990) describes principles governing these phonetic adaptations in terms of trade-offs: ''hyperarticulated'' speech is used to facilitate perception in contexts in which communication is harder or more important (e.g., slow and clear speech in a loud environment); otherwise, when perceptual demands are less severe, speech defaults to an articu-S Q U I B S A N D D I S C U S S I O N latorily easier form.…”

Tongue- and Jaw-Specific Contributions to Acoustic Vowel Contrast Changes in the Diphthong /ai/ in Response to Slow, Loud, and Clear Speech

“…Although clear speech is commonly produced with increased loudness, as well as a slower speaking rate (e.g., Ferguson & Quené, 2014;Lam et al, 2012;Picheny, Durlach, & Braida, 1986;Tjaden et al, 2013), the magnitude of change is much smaller in clear speech. In the current study, the relative change in vocal intensity in response to clear speech was similar to previously observed changes in vocal intensity during this speech modification .…”