This study is concerned with whether an asymmetric phonetic overlap between speaker groups contributes to the directional spread of sound change. An acoustic analysis of speakers of Southern British English showed that younger speakers’ fronted /u/ was probabilistically closer to that of older speakers’ retracted /u/ distributions than the other way around. Agent-based modeling based on the same data showed an asymmetric shift of older toward younger speakers’ fronted /u/. The general conclusion is that sound change is likely to be propagated when a phonetic bias within an individual is further magnified by a difference between speaker groups that is in the same direction.

Certain varieties in the Dutch and German language area distinguish two groups of words on the basis of different tonal melodies, a phenomenon called (Franconian) tonal accent. Despite extensive efforts, scholars are still far from reaching consensus on how this contrast may have developed. We show how both the accent genesis and distributional variation across dialects can be modeled by assuming that intrinsic durational differences between two sets of vowels formed the basis of the opposition. A key insight emerging from our scenario is that vowel-lengthening processes in open syllables must have been ongoing when apocope was completed, counter to the received view in Germanic historical phonology. Our analysis also addresses various broader issues concerning mechanisms of prosodic change, the interaction of sound changes, and the reliability of manuscript evidence.

What causes Indonesian to lenite word-final /k/, American English to lenite word-final /t/, and Spanish to lenite word-final /s/? This article shows that all three observed lenition patterns can be motivated using a single principle: languages preferentially lenite segments that provide relatively low informativity compared to the amount of informativity those segments carry in other languages. In a comparison of a diverse sample of seven languages from the LDC CALLHOME and CALLFRIEND corpora, Indonesian /k/, American English /t/, and Spanish /s/ are found to have the lowest informativity, predicting that they would be more likely to be affected by sound change processes. In a subsequent regression-based corpus study, low informativity predicted the propensity of word-final lenition of all obstruents in American English after phonetic and phonological factors were controlled for. This article therefore provides a partial solution to the famous actuation problem (Weinreich et al. 1968) with respect to the actuation of lenition processes.

How and why speakers differ in the phonetic implementation of phonological contrasts, and the relationship of this ‘structured heterogeneity’ to language change, has been a key focus over fifty years of variationist sociolinguistics. In phonetics, interest has recently grown in uncovering ‘structured variability’—how speakers can differ greatly in phonetic realization in nonrandom ways—as part of the long-standing goal of understanding variability in speech. The English stop voicing contrast, which combines extensive phonetic variability with phonological stability, provides an ideal setting for an approach to understanding structured variation in the sounds of a community's language that illuminates both synchrony and diachrony. This article examines the voicing contrast in a vernacular dialect (Glasgow Scots) in spontaneous speech, focusing on individual speaker variability within and across cues, including over time. Speakers differ greatly in the use of each of three phonetic cues to the contrast, while reliably using each one to differentiate voiced and voiceless stops. Interspeaker variability is highly structured: speakers lie along a continuum of use of each cue, as well as correlated use of two cues—voice onset time and closure voicing—along a single axis. Diachronic change occurs along this axis, toward a more aspiration-based and less voicing-based phonetic realization of the contrast, suggesting an important connection between synchronic and diachronic speaker variation.

This article investigates the development of the palatalization contrast in Slavic from diachronic, synchronic, and phonetic perspectives. The diachrony of this contrast is an important test case for theories of the actuation of sound change, since the Slavic language family shows an impressive diversity in the realization of the original contrast, with Russian, for instance, preserving the contrast, Slovak maintaining it only for some consonants, and Slovenian showing complete merger. A diachronic study of the contrast reveals a generalization about which consonant pairs are more or less likely to undergo merger, and an acoustic-phonetic study of Russian points to the aspects of synchronic phonetic variability that correlate with merger. We then use the methods of the acoustic theory of speech production and synchronic phonology to further understand the development of the sound change. The results and interpretation point to a tight interplay between phonetics and phonology in the realization of the change.

Inspired by Beddor 2009, this article explores whether and how trading relations between coarticulatory source and effect may serve as a precursor for sound change. It aims at extending the case of vowel nasalization examined by Beddor to the relationship between closure voicing (source) and co-intrinsic pitch (effect). Through four production and perception studies, we show that the inverse source-effect relation observed for vowel nasalization is not found in the voicing contrast of French, a true-voicing language. Instead, we propose that the phonologization of co-intrinsic pitch (a.k.a. tonogenesis) originates from spontaneous devoicing (a production bias), which subsequently triggers an upweighting of pitch (a perceptual adaptation strategy).

Vowels vary systematically in F0 based on intrinsic properties of the vowel (e.g. height: VF0) and preceding obstruent (e.g. voicing: CF0). These patterns have been attested in most languages studied, raising the possibility that they stem from physiological sources. However, previous results show a range of variability in maximum effect size and duration. One explanation is that variation could be learned and increased to enhance phonological contrasts or suppressed for functional reasons (e.g. for tone languages). Alternatively, differences could be due to physiological factors such as laryngeal contrast type. We map out the distribution of intrinsic F0 effects across twenty languages, using large corpora of read speech, operationalizing CF0 as the difference between stop series that most closely approximate phonologically ‘voiced’ and ‘voiceless’ stops. We find that both VF0 and CF0 effects are present and are in the same direction in all languages examined, but languages vary greatly in effect size. While some of this variability may be due to phonological properties of the languages (e.g. tone), and some variability in CF0 may be due to the diverse phonetic realizations of ‘voicing’ across languages, much of this variability remains to be explained. We find that the CF0 effect is consistently at least as large as the VF0 effect and is more variable across languages, suggesting a possible explanation for the tendency for CF0 effects to lead to sound change much more often than VF0 effects do. While our results on variability in CF0 effects rely on the validity of ‘lumping’ together diverse phonetic realizations, those on the robustness of CF0 and VF0 and on the variability in VF0 hold regardless. These results motivate further investigation to deepen our understanding of intrinsic F0 effects, their crosslinguistic distribution, and their role as precursors to sound change.

Distinguishing cognitive influences from historical influences on human behavior has long been a disputed topic in behavioral sciences, including linguistics. The discussion is often complicated due to empirical evidence being consistent with both the cognitive and the historical approach. This article argues that phonology offers a unique test case for distinguishing historical and cognitive influences on grammar, and it proposes an experimental technique for testing the cognitive factor which controls for the historical factor. The article outlines a model called CATALYSIS for explaining how learnability influences phonological typology and presents experiments that simulate this process. Central to this discussion are unnatural phonological processes, that is, those that operate against universal phonetic tendencies and require complex historical trajectories in order to arise. By using statistical methods for estimating historical influences, mismatches in predictions between the cognitive and historical approaches to typology can be identified. By conducting artificial grammar learning experiments on processes for which the historical approach makes predictions that differ from those of the cognitive approach, the experimental technique proposed in this article controls for historical influences while testing cognitive factors. Results of online and fieldwork experiments on two languages, English and Slovenian, show that subjects prefer postnasal devoicing over postnasal fricative occlusion and devoicing in at least a subset of places of articulation, which aligns with the observed typology. The advantage of the proposed approach over existing experimental work is that it experimentally confirms a link between synchronic preferences and typology that is most likely not influenced by historical biases. Results suggest that complexity avoidance is the primary influence cognitive bias has on phonological systems in human languages. Applying this technique to further alternations should yield new information about those cognitive properties of phonological grammar that are not conflated with historical influences.

The study of sound change in progress in Philadelphia has been facilitated by the application of forced alignment and automatic vowel measurement to a large corpus of neighborhood studies, including 379 speakers with dates of birth from 1888 to 1991. Two of the sound changes active in the 1970s show a linear pattern of incrementation in succeeding decades. The fronting of back upgliding vowels/aw/and/ow/shows a reversal in the direction of change, beginning with those born after 1940. The study also finds a general withdrawal from two salient features of local phonology, tense/æh/and/oh/, led by those with higher education. Younger speakers with higher education have also reorganized the traditional Philadelphia tense/lax split of short-a to form a nasal system with tensing before all and only nasal consonants. The development of the Philadelphia vowel system can be understood in the geographic context of neighboring dialects. Features in common with North and North Midland dialects have accelerated in use while features in common with South Midland and Southern dialects have been reversed in favor of Northern patterns. The microevolution of a linguistic system can be seen here as subject to phonological generalizations but driven by social evaluation as features rise in level of salience for members of the speech community.

Velum movement signals generated from real-time magnetic resonance imaging videos of thirty-five German speakers were used to investigate the physiological conditions that might promote sound change involving the development of contrastive vowel nasality. The results suggest that, in comparison to when a nasal consonant precedes a voiced obstruent, the velum gesture associated with a nasal consonant preceding a voiceless obstruent undergoes gestural rescaling and temporal rephasing. This further suggests that the diachronic development of contrastive vowel nasality comprises two stages: the first stage involves gestural shortening and realignment, while the second stage involves a trading relationship between source and effect.

The regularity of sound change as set out by the scholars of the late nineteenth century is a fundamental principle of historical linguistics. The principle as recognized by the Neogrammarian linguists states that once a sound change has begun, it affects every word in the vocabulary that contains the sound in question. The principle has been disputed by many linguists and especially dialectologists, who argue that ‘every word has its own history’. This article demonstrates how the Neogrammarian principle operates in one prototypical change in progress, the raising of the mid front long vowel /ey/ before a consonant in Philadelphia English. Mixed-level regression analysis shows consistent phonetic constraints across the nineteenth century, with no effect of word frequency. The regularity of sound change is reflected in the common pattern of behavior of the most frequent words, those of moderate frequency, and words that occur only once in the corpus.

Much progress has been made in the last 200 years with regard to understanding the origins and mechanisms of sound change. It is hypothesized that many sound changes originate in biomechanical constraints on speech production or in the misperception of sounds. These production and perception pressures explain a wide range of sound changes across the world's languages, yet we also know that sound change is not inevitable. For example, similar phonological structures have undergone change in many languages yet remained stable in others. In this study, we examine how typologically unusual contrasts are maintained in the face of intense pressures, in order to uncover the potential biomechanical, perceptual, and sociolinguistic factors that facilitate the maintenance of typologically unusual contrasts. We focus on secondary articulation contrasts in Scottish Gaelic rhotics, triangulating auditory, acoustic, and articulatory data in order to better understand the maintenance of contrast in the face of multidimensional typological challenges. Here, individual-level articulatory strategies are combined with contextual prosodic information in order to maintain acoustic and auditory distinctiveness across three rhotic phonemes. We highlight the need to more comprehensively consider typologically unusual and minority languages in order to test the limits of generalizations about crosslinguistic phonetic typology.

This article follows a change in pronunciation of word-medial intervocalic /t/ in New Zealand English, as it unfolds over 120 years. Data are analyzed in the context of questions about the role of experience-based lexical representations and their potential impact on the time course of sound change in progress. Three major results are reported. First, frequent words lead the change. Second, the distributions of individual words affect their participation in the change: words favored by younger speakers are produced with newer variants. Finally, the topic of conversation affects which variant is favored: older topics elicit older variants. Together, these findings provide evidence that phonetic distributions of word-level representations are implicated in the course of sound change.

An automated sound correspondence-recognition program developed by the authors is applied to a data set consisting of standardized word lists for over half of the world's languages. Online appendices present the results in a compendium of 692 recurrent sound correspondences that contains information about the frequency of occurrence of each correspondence. Applications of the compendium to historical linguistics are proposed. For example, the catalog of correspondences and frequencies facilitates objective assessment of the commonness or rarity of shared phonological innovations cited as evidence for language-family subgrouping. In another analysis, correspondence frequency is used to measure the degree of similarity between different sounds, yielding models for classifying consonants and vowels that substantially agree with articulatory properties. Correspondence-based similarities are also compared with measurements of sound similarity involving factors such as perceptual confusions, speech errors, and cooccurrence patterns in synchronic phonological rules. Sound similarity discerned from both the perception and production of speech is found to correlate to about the same extent with correspondence-based similarities.

This article proposes that patterns of phonological contrast should be added to the list of factors that influence sound change. It adopts a hierarchically determined model of contrast that allows for a constrained degree of crosslinguistic variation in contrastive feature specifications. The predictions of this model are tested against a database comprising the set of vowel changes in the Al-gonquian languages. The model reveals striking commonalities in the underlying sources of these changes and straightforwardly predicts the previously unrecognized patterning of the languages into two groups: (i) those in which */ε/tends to merge with */i/and palatalization is triggered by */i/, and (ii) those in which */ε/tends to merge with */a/and palatalization is triggered by */ε/. In addition to providing a new argument for the relevance of contrast to phonology, the model also gives us a way to import traditional philological findings into a framework that brings them to bear on theoretical questions.

This article is an analysis of the claim that a universal ban on certain (‘anti-markedness’) grammars is necessary in order to explain their nonoccurrence in the languages of the world. Such a claim is based on the following assumptions: that phonological typology shows a highly asymmetric distribution, and that such a distribution cannot possibly arise ‘naturally’—that is, without a universal grammar-based restriction of the learner’s hypothesis space. Attempting to test this claim reveals a number of open issues in linguistic theory. In the first place, there exist critical aspects of synchronic theory that are not specified explicitly enough to implement computationally. Second, there remain many aspects of linguistic competence, language acquisition, sound change, and even typology that are still unknown. It is not currently possible, therefore, to reach a definitive conclusion about the necessity, or lack thereof, of an innate substantive grammar module. This article thus serves two main functions: acting both as a pointer to the areas of phonological theory that require further development, especially at the overlap between traditionally separate subdomains, and as a template for the type of argumentation required to defend or attack claims about phonological universals.

Understanding the relation between speech production and perception is foundational to phonetic theory, and is similarly central to theories of the phonetics of sound change. For sound changes that are arguably perceptually motivated, it is particularly important to establish that an individual listener's selective attention—for example, to the redundant information afforded by coarticulation—is reflected in that individual's own productions. This study reports the results of a pair of experiments designed to test the hypothesis that individuals who produce more consistent and extensive coarticulation will attend to that information especially closely in perception. The production experiment used nasal airflow to measure the time course of participants' coarticulatory vowel nasalization; the perception experiment used an eye-tracking paradigm to measure the time course of those same participants' attention to coarticulated nasality. Results showed that a speaker's coarticulatory patterns predicted, to some degree, that individual's perception, thereby supporting the hypothesis: participants who produced earlier onset of coarticulatory nasalization were, as listeners, more efficient users of nasality as that information unfolded over time. Thus, an individual's perception of coarticulated speech is made public through their productions.