Volume 3, Issue 2

We discuss what factors influence the acquisition of morphophonemic alternations. What mechanisms are available to the learner; what is the basis for grammatical generalizations? Using the Artificial Language Paradigm we compared the acquisition of three alternations differing in phonetic substance, locality, and amount of exposure: one alternation was substantively based and structurally local, another one was structurally local but not substantively based, and the last alternation was neither substantively based nor structurally local. Within each alternation we exposed the experimental groups to a greater or smaller number of instances. Results show a clear advantage for the substantively based alternation during acquisition. In addition, the local dependency has an advantage over the non-local one and alternations that are presented frequently have an advantage over those that are presented infrequently. We show that all three factors influence the acquisition of morphophonemic alternations, but they do so to a different degree. Phonetic substance causes the strongest boost in the acquisition process and builds on locality, which also plays a role, and amount of exposure influences the acquisition process independent of the nature of the alternation. We argue that acquisition models should take the interaction of these factors into account.

While the role of auditory saliency is well accepted as providing insight into the shaping of phonological systems, the influence of visual saliency on such systems has been neglected. This paper provides evidence for the importance of visual information in historical phonological change and synchronic variation through a series of audio-visual experiments with the /f/∼/θ/ contrast. /θ/ is typologically rare, an atypical target in sound change, acquired comparatively late, and synchronically variable in language inventories. Previous explanations for these patterns have focused on either the articulatory difficulty of an interdental tongue gesture or the perceptual similarity /θ/ shares with labiodental fricatives. We hypothesize that the bias is due to an asymmetry in audio-visual phonetic cues and cue variability within and across talkers. Support for this hypothesis comes from a speech perception study that explored the weighting of audio and visual cues for /f/ and /θ/ identification in CV, VC, and VCV syllabic environments in /i/, /a/, or /u/ vowel contexts in Audio, Visual, and Audio-Visual experimental conditions using stimuli from ten different talkers. The results indicate that /θ/ is more variable than /f/, both in Audio and Visual conditions. We propose that it is this variability which contributes to the unstable nature of /θ/ across time and offers an improved explanation for the observed synchronic and diachronic asymmetries in its patterning.

This paper addresses the claim that Dutch /l/ triggers laxing of preceding tense mid vowels (/e ø o/), and that this leads to a phonetic length contrast between tense and lax vowels, e.g., tense speel [spɪːɫ] ‘play’ vs. lax spil [spɪɫ] ‘pivot’. The production experiment reported in this paper shows that this claim is incorrect. We find instead that /l/ triggers retraction of both tense and lax mid vowels, which leads neither to complete neutralization of quality nor to complete neutralization of length.

This paper shows that several typologically unrelated languages share the tendency for voiced sibilant affricates to be infrequent or missing altogether. Phonological processes examined in the paper illustrate that (1) voiceless stops undergo affrication more readily than voiced ones, and (2) voiced affricates deaffricate more commonly than voiceless ones, thereby contributing to the asymmetry in frequency between voiced vs. voiceless affricates. Phonetic properties of the sounds may explain these patterns. Affricates in general require complex control over supralaryngeal apertures, and they appear to have long durations in many languages. Long duration and complete oral closure at the beginning of affricates contribute to a buildup of intraoral pressure which impedes phonation. An aerodynamic experiment of obstruents, including affricates, was carried out for Polish and German, languages which differ in their realization of the stop voicing contrast (viz., voicing vs. aspiration). Voiced affricates in Polish had significantly longer voicing than in German; in medial position, they also had shorter durations and lower peak pressure values. We suggest that languages having voiced affricates in their phoneme inventory may tend to limit duration and intraoral pressure buildup in these sounds to allow vocal-fold vibration to continue.

Recent evidence that pitch-movement shape can influence perceived alignment of rising (LH) pitch accents in several languages appears to challenge the well-established level-based approach to intonation embodied in the AM model, wherein it is typically assumed that the alignment and scaling of well-defined turning points (TPs) in the F 0 contour are the primary phonetic correlates of contrastive accent category. Here we present the results of two experiments, arguing that a new approach to tonal implementation succeeds in reconciling these apparent contradictions. This approach, based on the notion of a perceptual reference point called Tonal Center of Gravity (TCoG), treats information about contour shape and TP-localization not in ‘either-or’ terms, but rather as two sets of cues working in a fundamentally synergistic way toward a single perceptual end: the alignment and scaling of TCoG. Experiment 1 shows that TCoG-based models can perform better at distinguishing productions of English L+H* and L*+H pitch accents than comparable TP-only-based models; Experiment 2 shows that TCoG is more robust than TP-only-based models to ambiguities in TP localization commonly encountered in F 0 signals from natural speech. TCoG is shown to capture key insights of movement-based approaches to intonation, without abandoning the central advantages of level-based approaches like AM.

This study investigates the use of prosodic information in the segmentation of French speech by mid-level and high-level English second/foreign language (L2) learners of French and native French listeners. The results of two word-monitoring tasks, one with natural stimuli and one with resynthesized stimuli, show that as L2 learners become more proficient in French, they go from parsing accented syllables as word-initial to parsing them as word-final, but unlike native listeners, they use duration increase but not fundamental frequencyx ( F 0 ) rise as a cue to word-final boundaries. These results are attributed to: (1) the L2 learners' native language, in which F 0 rise is a reliable cue to word-initial boundaries but not word-final boundaries; (2) the co-occurrence of F 0 and duration cues in word-final syllables in French, rendering L2 learners' use of F 0 rise unnecessary for locating word-final boundaries; and (3) the optional marking of word-initial boundaries by F 0 cues in French, thus making it difficult for non-native listeners to tease the two types of F 0 rise apart. We argue that these factors prevent English listeners from attending to F 0 rise as a cue to word-final boundaries in French, irrespective of their proficiency in French.

During normal sign language use, a signer's productions will often be reduced from the citation forms of signs. This study examines a form of phonetic reduction in American Sign Language, in which signs that are located at the forehead are lowered in space. In particular, we explore the effects of signing rate and phonetic environment on the lowering of specific ASL signs and on their phonetic variation along the other two movement axes. Movement data were captured as native signers produced utterances that were controlled for phonetic environment and signing rate. We found that all signers produced lowered forms as an effect of the phonetic factors that we manipulated. In addition, several rate-induced effects occurred, which we had not predicted. Results are discussed in relation to past research on variation in sign production and in speech.

In spontaneous speech, words may be realised shorter than in formal speech (e.g., English yesterday may be pronounced like [jɛʃeɩ]). Previous research has shown that context is required to understand highly reduced pronunciation variants. We investigated the extent to which listeners can predict low predictability reduced words on the basis of the semantic/syntactic and acoustic cues in their context. In four experiments, participants were presented with either the preceding context or the preceding and following context of reduced words, and either heard these fragments of conversational speech, or read their orthographic transcriptions. Participants were asked to predict the missing reduced word on the basis of the context alone, choosing from four plausible options. Participants made use of acoustic cues in the context, although casual speech typically has a high speech rate, and acoustic cues are much more unclear than in careful speech. Moreover, they relied on semantic/syntactic cues. Whenever there was a conflict between acoustic and semantic/syntactic contextual cues, measured as the word's probability given the surrounding words, listeners relied more heavily on acoustic cues. Further, context appeared generally insufficient to predict the reduced words, underpinning the significance of the acoustic characteristics of the reduced words themselves.