Acoustic cues to lexical segmentation: A study of resynthesized speech

Abstract

It has been posited that the role of prosody in lexical segmentation is elevated when the speech signal is degraded or unreliable. Using predictions from Cutler and Norris' [J. Exp. Psychol. Hum. Percept. Perform. 14, 113-121 (1988)] metrical segmentation strategy hypothesis as a framework, this investigation examined how individual suprasegmental and segmental cues to syllabic stress contribute differentially to the recognition of strong and weak syllables for the purpose of lexical segmentation. Syllabic contrastivity was reduced in resynthesized phrases by systematically (i) flattening the fundamental frequency (F0) contours, (ii) equalizing vowel durations, (iii) weakening strong vowels, (iv) combining the two suprasegmental cues, i.e., F0 and duration, and (v) combining the manipulation of all cues. Results indicated that, despite similar decrements in overall intelligibility, F0 flattening and the weakening of strong vowels had a greater impact on lexical segmentation than did equalizing vowel duration. Both combined-cue conditions resulted in greater decrements in intelligibility, but with no additional negative impact on lexical segmentation. The results support the notion of F0 variation and vowel quality as primary conduits for stress-based segmentation and suggest that the effectiveness of stress-based segmentation with degraded speech must be investigated relative to the suprasegmental and segmental impoverishments occasioned by each particular degradation.

Neural Entrainment to the Rhythmic Structure of Music

“…Another open question is whether the ability to track rhythmic structure despite conflicting information relates to language skills. Durational cues can be a useful cue for word segregation (Mattys, 2004;Cutler & Butterfield, 1992;Smith, Cutler, Butterfield, & Nimmo-Smith, 1989;Nakatani & Schaffer, 1977), especially when speech is presented in noise (Spitzer, Liss, & Mattys, 2007). Thus, the ability to ignore distractor stimuli (background talkers) when tracking rhythm from a particular sound source (a target talker) may be useful for both music and speech processing.…”

The Use of Prosodic Cues in Learning New Words in an Unfamiliar Language

“…Finally, the fi nal lengthening cue was combined with F0 rise to assess whether a combination of potential prosodic cues to phrase-fi nal position can help lexical segmentation in a cumulative way-that is, whether listeners benefi t more when they are exposed to lengthening and F0 rise cues together, as opposed to when they are exposed to one cue at a time. Some previous work has suggested that listeners might be able to use available segmentation cues in a cumulative way (Spitzer, Liss, & Mattys, 2007 ). If this were the case, both Korean and Dutch listeners' learning performance may improve with the use of combined cues as opposed to just one prosodic cue.…”

Clear Speech Variants: An Acoustic Study in Parkinson's Disease

“…Among nonhabitual conditions, both measures of F0 tended to be maximized in the hearing impaired condition, followed by the overenunciate condition and then the clear condition. Sentence-level F0 range has further been proposed to be of perceptual importance, whereby narrower ranges have been associated with a decrease in intelligibility (Binns & Culling, 2007;Bunton, Kent, Kent, & Rosenbek, 2000;Laures & Bunton, 2003;Laures & Weismer, 1999;Miller, Schlauch, & Watson, 2010;Mori, Kobayashi, Kasuya, Kobayashi, & Hirose, 2005;Spitzer, Liss, & Mattys, 2007;Watson & Schlauch, 2008). Thus, further investigating the acoustic-perceptual relationship between F0 and intelligibility is of importance in identifying the clear speech variants that best maximize intelligibility.…”