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• Vocal reactions to the offset of speech-like stimuli are longer than reactions to stimulus onsets. • Speaking latencies decrease as prosodic cues appear further away from stimulus ends. • Slower speech rates produced slower responses for stimuli lacking prosodic cues. • Turn transitions taking less than 200 ms are unlikely to involve reactions to the end of a turn. • Turn transitions taking less than 200 ms can be achieved when turn-final prosodic cues are available. Everyday conversation is characterized by a rapid alternation of turns among successive speakers. We investigate vocal reaction times to speech offsets in order to shed light on the limits of reactive behavior in conversational turn-taking. Twenty-three speakers of Dutch produced a prepared response ([ja], 'yes') as fast as possible in response to (a) the onset of a pure tone preceded by a variable amount of silence, and (b) the offset of several types of speech-like auditory stimuli varying in duration, prosodic characteristics, and speech rate. Reactions to the offset of stimuli lacking final prosodic cues were significantly longer than reactions to stimulus onsets (283 vs. 215 ms on average), and were rare below 200 ms (3%). Speaking latencies decreased as prosodic cues appeared further away from the stimulus end. Slowing down the speech rate produced an entrainment effect (i.e. slower responses) for stimuli lacking prosodic cues vs. a facilitatory effect (i.e. faster responses) when prosodic cues were present. These findings suggest that smooth turn transitions taking less than 200 ms are unlikely to involve reactions to silence at the end of a turn, but that they can be achieved when turn-final prosodic cues are available. [ABSTRACT FROM AUTHOR]

In conversation, turn transitions between speakers often occur smoothly, usually within a time window of a few hundred milliseconds. It has been argued, on the basis of a button-press experiment [De Ruiter, J. P., Mitterer, H., & Enfield, N. J. (2006). Projecting the end of a speaker's turn: A cognitive cornerstone of conversation. Language , 82 (3):515–535], that participants in conversation rely mainly on lexico-syntactic information when timing and producing their turns, and that they do not need to make use of intonational cues to achieve smooth transitions and avoid overlaps. In contrast to this view, but in line with previous observational studies, our results from a dialogue task and a button-press task involving questions and answers indicate that the identification of the end of intonational phrases is necessary for smooth turn-taking. In both tasks, participants never responded to questions (i.e., gave an answer or pressed a button to indicate a turn end) at turn-internal points of syntactic completion in the absence of an intonational phrase boundary. Moreover, in the button-press task, they often pressed the button at the same point of syntactic completion when the final word of an intonational phrase was cross-spliced at that location. Furthermore, truncated stimuli ending in a syntactic completion point but lacking an intonational phrase boundary led to significantly delayed button presses. In light of these results, we argue that earlier claims that intonation is not necessary for correct turn-end projection are misguided, and that research on turn-taking should continue to consider intonation as a source of turn-end cues along with other linguistic and communicative phenomena. [ABSTRACT FROM AUTHOR]

The study of phonetic contrasts and related phenomena, e.g. inter- and intra-speaker variability, often requires to analyse data in the form of measured time series, like f 0 contours and formant trajectories. As a consequence, the investigator has to find suitable ways to reduce the raw and abundant numerical information contained in a bundle of time series into a small but sufficient set of numerical descriptors of their shape. This approach requires one to decide in advance which dynamic traits to include in the analysis and which not. For example, a rising pitch gesture may be represented by its duration and slope, hence reducing it to a straight segment, or by a richer coding specifying also whether (and how much) the rising contour is concave or convex, the latter being irrelevant in some context but crucial in others. Decisions become even more complex when a phenomenon is described by a multidimensional time series, e.g. by the first two formants. In this paper we introduce a methodology based on Functional Data Analysis (FDA) that allows the investigator to delegate most of the decisions involved in the quantitative description of multidimensional time series to the data themselves. FDA produces a data-driven parametrisation of the main shape traits present in the data that is visually interpretable, in the same way as slopes or peak heights are. These output parameters are numbers that are amenable to ordinary statistical analysis, e.g. linear (mixed effects) models. FDA is also able to capture correlations among different dimensions of a time series, e.g. between formants F 1 and F 2 . We present FDA by means of an extended case study on diphthong – hiatus distinction in Spanish, a contrast that involves duration, formant trajectories and pitch contours. [ABSTRACT FROM AUTHOR]

Abstract: This study investigates the reduction of vowel /e/ in the French word c’était // ‘it was’. This reduction phenomenon appeared to be highly frequent, as more than half of the occurrences of this word in a corpus of casual French contained few or no acoustic traces of a vowel between [s] and [t]. All our durational analyses clearly supported a categorical absence of vowel /e/ in a subset of c’était tokens. This interpretation was also supported by our finding that the occurrence of complete elision and [e] duration in non-elision tokens were conditioned by different factors. However, spectral measures were consistent with the possibility that a highly reduced /e/ vowel is still present in elision tokens in spite of the durational evidence for categorical elision. We discuss how these findings can be reconciled, and conclude that acoustic analysis of uncontrolled materials can provide valuable information about the mechanisms underlying reduction phenomena in casual speech. [Copyright &y& Elsevier]

Abstract: This paper addresses the validity of the segmental anchoring hypothesis for tonal landmarks (henceforth, SAH) as described in recent work by (among others) Ladd, Faulkner, D., Faulkner, H., & Schepman [1999. Constant ‘segmental’ anchoring of f0 movements under changes in speech rate. Journal of the Acoustical Society of America, 106, 1543–1554], Ladd [2003. Phonological conditioning of f0 target alignment. In: M. J. Solé, D. Recasens, & J. Romero (Eds.), Proceedings of the XVth international congress of phonetic sciences, Vol. 1, (pp. 249–252). Barcelona: Causal Productions; in press. Segmental anchoring of pitch movements: Autosegmental association or gestural coordination? Italian Journal of Linguistics, 18 (1)]. The alignment of LH* prenuclear peaks with segmental landmarks in controlled speech materials in Peninsular Spanish is analyzed as a function of syllable structure type (open, closed) of the accented syllable, segmental composition, and speaking rate. Contrary to the predictions of the SAH, alignment was affected by syllable structure and speech rate in significant and consistent ways. In: CV syllables the peak was located around the end of the accented vowel, and in CVC syllables around the beginning-mid part of the sonorant coda, but still far from the syllable boundary. With respect to the effects of rate, peaks were located earlier in the syllable as speech rate decreased. The results suggest that the accent gestures under study are synchronized with the syllable unit. In general, the longer the syllable, the longer the rise time. Thus the fundamental idea of the anchoring hypothesis can be taken as still valid. On the other hand, the tonal alignment patterns reported here can be interpreted as the outcome of distinct modes of gestural coordination in syllable-initial vs. syllable-final position: gestures at syllable onsets appear to be more tightly coordinated than gestures at the end of syllables [Browman, C. P., & Goldstein, L.M. (1986). Towards an articulatory phonology. Phonology Yearbook, 3, 219–252; Browman, C. P., & Goldstein, L. (1988). Some notes on syllable structure in articulatory phonology. Phonetica, 45, 140–155; (1992). Articulatory Phonology: An overview. Phonetica, 49, 155–180; Krakow (1999). Physiological organization of syllables: A review. Journal of Phonetics, 27, 23–54; among others]. Intergestural timing can thus provide a unifying explanation for (1) the contrasting behavior between the precise synchronization of L valleys with the onset of the syllable and the more variable timing of the end of the f0 rise, and, more specifically, for (2) the right-hand tonal pressure effects and ‘undershoot’ patterns displayed by peaks at the ends of syllables and other prosodic domains. [Copyright &y& Elsevier]

• Between the Mandarin flat-falling tonal contrast, F0 range imitation is non-linear while duration imitation is linear. • Phonological contrast mediates the imitation of 'supra-segmental' features. • Phonological mediation on imitation is dependent on cue primacy. • A Bayesian mixture model is used to examine the categorical imitation pattern. Phonetic imitation has been found to be mediated by phonological contrast. For features whose values vary around a phonological prototype, the imitation is distorted by the phonological category, i.e., the imitation is nonlinear. This phonological mediation effect was mostly found in segmental features such as VOT and formants. Supra-segmental features, on the contrary, are generally found to be easy to imitate, i.e., the imitation is linear. Nevertheless, whether the phonological effect exists in the imitation of supra-segmental features is not fully understood. This study, through an imitation experiment of Mandarin flat-falling tonal continua, examined whether a supra-segmental feature would be linearly imitated when it is the primary cue (F0 range) and the non-primary cue (duration) to the tonal contrast, respectively. Results showed that F0 range imitation was non-linear while duration imitation was linear. This reveals that the phonological effect is stronger in mediating imitation than would be predicted by the general hypothesis that supra-segmental features are easier to imitate. [ABSTRACT FROM AUTHOR]