Publications

Abstract

Cross-signing—the emergence of an interlanguage between users of different sign languages—offers a rare chance to examine the evolution of a natural communication system in real time. To provide an insight into this process, we analyse an annotated video corpus of 340 minutes of interaction between signers of different language backgrounds on their first meeting and after living with each other for several weeks. We focus on the evolution of shared color terms and examine the role of different selectional pressures, including frequency, content, coordination and interactional context. We show that attentional factors in interaction play a crucial role. This suggests that understanding meta-communication is critical for explaining the cultural evolution of linguistic systems.

Abstract

The deep structural diversity of languages suggests that our language capacities are not based on
any single template but rather on an underlying ability and motivation for infants to acquire a
culturally transmitted system. The hypothesis is that this ability has an interactional base that has
discernable precursors in other primates. In this paper I explore a specific evolutionary route for the
most puzzling aspect of this interactional base in humans, namely the development of an empathetic
intentional stance. The route involves a generalization of mother-infant interaction patterns to all
adults via a process (‘ cuteness selection’ ) analogous to, but distinct from, RA Fisher’s runaway
sexual selection. This provides a cornerstone for the carrying capacity for language.

Abstract

This is a comprehensive description of a language spoken some 450 km offshore from the mainland of Papua New Guinea. The language is remarkable for its phonological, morphological and syntactic complexity. As the sole surviving member of its language family, and with little historical contact with surrounding languages, the language provides evidence of the kind of languages spoken in this part of the world before the Austronesian expansion.

The grammar provides detailed information on the phoneme inventory, morphology, syntax and select semantic fields. Remarkable features include a 90 phoneme inventory including unique sounds, a morphology with thousands of non-compositional portmanteau elements, complex rules for negation, and extensive ergative syntax. Unusual patterns are also found in the organization of semantic fields, for example in partonymies of the body, taxonomies of the natural world, verbal semantics and kinship terms. The combination of linguistic ‘rara’ suggest that linguistic evolution under low contact can yield baroque and unusual patterns. The volume should be of special interest to linguists, typologists, sociolinguists, anthropologists and researchers in Oceania and Melanesia.

Abstract

In human communication, when the speech is disrupted, the visual channel (e.g. manual gestures) can compensate to ensure successful communication. Whether speech also compensates when the visual channel is disrupted is an open question, and one that significantly bears on the status of the gestural modality. We test whether gesture and speech are dynamically co-adapted to meet communicative needs. To this end, we parametrically reduce visibility during casual conversational interaction and measure the effects on speakers' communicative behaviour using motion tracking and manual annotation for kinematic and acoustic analyses. We found that visual signalling effort was flexibly adapted in response to a decrease in visual quality (especially motion energy, gesture rate, size, velocity and hold-time). Interestingly, speech was also affected: speech intensity increased in response to reduced visual quality (particularly in speech-gesture utterances, but independently of kinematics). Our findings highlight that multi-modal communicative behaviours are flexibly adapted at multiple scales of measurement and question the notion that gesture plays an inferior role to speech.

Abstract

Precision turn-taking may constitute a crucial part of the human endowment for communication. If so, it should be implemented similarly across language modalities, as in signed vs. spoken language. Here in the first experimental study of turn-end prediction in sign language, we find support for the idea that signed language, like spoken language, involves turn-type prediction and turn-end anticipation. In both cases, turns eliciting specific responses like questions accelerate anticipation. We also show remarkable cross-modality predictive capacity: non-signers anticipate sign turn-ends surprisingly well. Finally, we show that despite non-signers’ ability to intuitively predict signed turn-ends, early native signers do it much better by using their access to linguistic signals (here, question markers). As shown in prior work, question formation facilitates prediction, and age of sign language acquisition affects accuracy. The study thus sheds light on the kind of features that may facilitate turn-taking universally, and those that are language-specific.

Abstract

The evolution of basic color terms in language is claimed to be stimulated by technological development, involving technological control of color or exposure to artificially colored objects. Accordingly, technologically “simple” non-industrialized societies are expected to have poor lexicalization of color, i.e., only rudimentary lexica of 2, 3 or 4 basic color terms, with unnamed gaps in the color space. While it may indeed be the case that technology stimulates lexical growth of color terms, it is sometimes considered a sine qua non for color salience and lexicalization. We provide novel evidence that this overlooks the role of the natural environment, and people's engagement with the environment, in the evolution of color vocabulary. We introduce the Maniq—nomadic hunter-gatherers with no color technology, but who have a basic color lexicon of 6 or 7 terms, thus of the same order as large languages like Vietnamese and Hausa, and who routinely talk about color. We examine color language in Maniq and compare it to available data in other languages to demonstrate it has remarkably high consensual color term usage, on a par with English, and high coding efficiency. This shows colors can matter even for non-industrialized societies, suggesting technology is not necessary for color language. Instead, factors such as perceptual prominence of color in natural environments, its practical usefulness across communicative contexts, and symbolic importance can all stimulate elaboration of color language.

Abstract

In conversation, turn-taking is usually fluid, with next speakers taking their turn right after the end of the previous turn. Most, but not all, previous studies show that next speakers start to plan their turn early, if possible already during the incoming turn. The present study makes use of the list-completion paradigm (Barthel et al., 2016), analyzing speech onset latencies and eye-movements of participants in a task-oriented dialogue with a confederate. The measures are used to disentangle the contributions to the timing of turn-taking of early planning of content on the one hand and initiation of articulation as a reaction to the upcoming turn-end on the other hand. Participants named objects visible on their computer screen in response to utterances that did, or did not, contain lexical and prosodic cues to the end of the incoming turn. In the presence of an early lexical cue, participants showed earlier gaze shifts toward the target objects and responded faster than in its absence, whereas the presence of a late intonational cue only led to faster response times and did not affect the timing of participants' eye movements. The results show that with a combination of eye-movement and turn-transition time measures it is possible to tease apart the effects of early planning and response initiation on turn timing. They are consistent with models of turn-taking that assume that next speakers (a) start planning their response as soon as the incoming turn's message can be understood and (b) monitor the incoming turn for cues to turn-completion so as to initiate their response when turn-transition becomes relevant

Abstract

This paper reviews the prospects for the cross-fertilization of conversation-analytic (CA) and neurocognitive studies of conversation, focusing on turn-taking. Although conversation is the primary ecological niche for language use, relatively little brain research has focused on interactive language use, partly due to the challenges of using brain-imaging methods that are controlled enough to perform sound experiments, but still reflect the rich and spontaneous nature of conversation. Recently, though, brain researchers have started to investigate conversational phenomena, for example by using 'overhearer' or controlled interaction paradigms. We review neuroimaging studies related to turn-taking and sequence organization, phenomena historically described by CA. These studies for example show early action recognition and immediate planning of responses midway during an incoming turn. The review discusses studies with an eye to a fruitful interchange between CA and neuroimaging research on conversation and an indication of how these disciplines can benefit from each other.

Abstract

Understanding how and why language subsystems differ in their evolutionary dynamics is a fundamental question for historical and comparative linguistics. One key dynamic is the rate of language change. While it is commonly thought that the rapid rate of change hampers the reconstruction of deep language relationships beyond 6,000–10,000 y, there are suggestions that grammatical structures might retain more signal over time than other subsystems, such as basic vocabulary. In this study, we use a Dirichlet process mixture model to infer the rates of change in lexical and grammatical data from 81 Austronesian languages. We show that, on average, most grammatical features actually change faster than items of basic vocabulary. The grammatical data show less schismogenesis, higher rates of homoplasy, and more bursts of contact-induced change than the basic vocabulary data. However, there is a core of grammatical and lexical features that are highly stable. These findings suggest that different subsystems of language have differing dynamics and that careful, nuanced models of language change will be needed to extract deeper signal from the noise of parallel evolution, areal readaptation, and contact.

Abstract

Does blinking function as a type of feedback in conversation? To address this question, we built a corpus of Dutch conversations, identified short and long addressee blinks during extended turns, and measured their occurrence relative to the end of turn constructional units (TCUs), the location
where feedback typically occurs. Addressee blinks were indeed timed to the
end of TCUs. Also, long blinks were more likely than short blinks to occur
during mutual gaze, with nods or continuers, and their occurrence was
restricted to sequential contexts in which signaling understanding was
particularly relevant, suggesting a special signaling capacity of long blinks.

Abstract

The essential insight of speech act theory was that when we use language, we perform actions—in a more modern parlance, core language use in interaction is a form of joint action. Over the last thirty years, speech acts have been relatively neglected in linguistic pragmatics, although important work has been done especially in conversation analysis. Here we review the core issues—the identifying characteristics, the degree of universality, the problem of multiple functions, and the puzzle of speech act recognition. Special attention is drawn to the role of conversation structure, probabilistic linguistic cues, and plan or sequence inference in speech act recognition, and to the centrality of deep recursive structures in sequences of speech acts in conversation

Abstract

In every-day conversations, the gap between turns of conversational partners is most frequently between 0 and 200 ms. We were interested how speakers achieve such fast transitions. We designed an experiment in which participants listened to pre-recorded questions about images presented on a screen and were asked to answer these questions. We tested whether speakers already prepare their answers while they listen to questions and whether they can prepare for the time of articulation by anticipating when questions end. In the experiment, it was possible to guess the answer at the beginning of the questions in half of the experimental trials. We also manipulated whether it was possible to predict the length of the last word of the questions. The results suggest when listeners know the answer early they start speech production already during the questions. Speakers can also time when to speak by predicting the duration of turns. These temporal predictions can be based on the length of anticipated words and on the overall probability of turn durations.

Abstract

This paper outlines a first attempt to model the special constraints that arise in language processing in conversation, and to explore the implications such functional considerations may have on language typology and language change. In particular, we focus on processing pressures imposed by conversational turn-taking and their consequences for the cultural evolution of the structural properties of language. We present an agent-based model of cultural evolution where agents take turns at talk in conversation. When the start of planning for the next turn is constrained by the position of the verb, the stable distribution of dominant word orders across languages evolves to match the actual distribution reasonably well. We suggest that the interface of cognition and interaction should be a more central part of the story of language evolution.

Abstract

In conversation, interlocutors rarely leave long gaps between turns, suggesting that next speak- ers begin to plan their turns while listening to the previous speaker. The present experiment used analyses of speech onset latencies and eye-movements in a task-oriented dialogue paradigm to investigate when speakers start planning their response. Adult German participants heard a confederate describe sets of objects in utterances that either ended in a noun (e.g. Ich habe eine Tür und ein Fahrrad (‘I have a door and a bicycle’)) or a verb form (Ich habe eine Tür und ein Fahrrad besorgt (‘I have gotten a door and a bicycle’)), while the presence or absence of the final verb either was or was not predictable from the preceding sentence structure. In response, participants had to name any unnamed objects they could see in their own display in utterances such as Ich habe ein Ei (‘I have an egg’). The main question was when participants started to plan their response. The results are consistent with the view that speakers begin to plan their turn as soon as sufficient information is available to do so, irrespective of further incoming words.

Abstract

The core use of language is in face-to-face conversation. This is characterized by rapid turn-taking. This turn-taking poses a number central puzzles for the psychology of language.

Consider, for example, that in large corpora the gap between turns is on the order of 100 to 300 ms, but the latencies involved in language production require minimally between 600ms (for a single word) or 1500 ms (for as simple sentence). This implies that participants in conversation are predicting the ends of the incoming turn and preparing in advance. But how is this done? What aspects of this prediction are done when? What happens when the prediction is wrong? What stops participants coming in too early? If the system is running on prediction, why is there consistently a mode of 100 to 300 ms in response time?

The timing puzzle raises further puzzles: it seems that comprehension must run parallel with the preparation for production, but it has been presumed that there are strict cognitive limitations on more than one central process running at a time. How is this bottleneck overcome? Far from being 'easy' as some psychologists have suggested, conversation may be one of the most demanding cognitive tasks in our everyday lives. Further questions naturally arise: how do children learn to master this demanding task, and what is the developmental trajectory in this domain?

Research shows that aspects of turn-taking such as its timing are remarkably stable across languages and cultures, but the word order of languages varies enormously. How then does prediction of the incoming turn work when the verb (often the informational nugget in a clause) is at the end? Conversely, how can production work fast enough in languages that have the verb at the beginning, thereby requiring early planning of the whole clause? What happens when one changes modality, as in sign languages -- with the loss of channel constraints is turn-taking much freer? And what about face-to-face communication amongst hearing individuals -- do gestures, gaze, and other body behaviors facilitate turn-taking? One can also ask the phylogenetic question: how did such a system evolve? There seem to be parallels (analogies) in duetting bird species, and in a variety of monkey species, but there is little evidence of anything like this among the great apes.

All this constitutes a neglected set of problems at the heart of the psychology of language and of the language sciences. This research topic welcomes contributions from right across the board, for example from psycholinguists, developmental psychologists, students of dialogue and conversation analysis, linguists interested in the use of language, phoneticians, corpus analysts and comparative ethologists or psychologists. We welcome contributions of all sorts, for example original research papers, opinion pieces, and reviews of work in subfields that may not be fully understood in other subfields.

Abstract

This commentary raises two issues: (1) Language processing is hastened not only by internal pressures but also externally by turntaking in language use; (2) the theory requires nested levels of processing, but linguistic levels do not fully nest; further, it would seem to require multiple memory buffers, otherwise there’s no obvious treatment for discontinuous structures, or for verbatim recall.

Abstract

Most language usage is interactive, involving rapid turn-taking. The turn-taking system has a number of striking properties: turns are short and responses are remarkably rapid, but turns are of varying length and often of very complex construction such that the underlying cognitive processing is highly compressed. Although neglected in cognitive science, the system has deep implications for language processing and acquisition that are only now becoming clear. Appearing earlier in ontogeny than linguistic competence, it is also found across all the major primate clades. This suggests a possible phylogenetic continuity, which may provide key insights into language evolution.