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We present an analytical framework aimed at predicting the local brain activity in uncontrolled experimental conditions based on multimodal recordings of participants' behavior, and its application to a corpus of participants having conversations with another human or a conversational humanoid robot. The framework consists in extracting high-level features from the raw behavioral recordings and applying a dynamic prediction of binarized fMRI-recorded local brain activity using these behavioral features. The objective is to identify behavioral features required for this prediction, and their relative weights, depending on the brain area under investigation and the experimental condition. In order to validate our framework, we use a corpus of uncontrolled conversations of participants with a human or a robotic agent, focusing on brain regions involved in speech processing, and more generally in social interactions. The framework not only predicts local brain activity significantly better than random, it also quantifies the weights of behavioral features required for this prediction, depending on the brain area under investigation and on the nature of the conversational partner. In the left Superior Temporal Sulcus, perceived speech is the most important behavioral feature for predicting brain activity, regardless of the agent, while several features, which differ between the human and robot interlocutors, contribute to the prediction in regions involved in social cognition, such as the TemporoParietal Junction. This framework therefore allows us to study how multiple behavioral signals from different modalities are integrated in individual brain regions during complex social interactions.

Understanding children's conversational skills is crucial for understanding their social, cognitive, and linguistic development, with important applications in health and education. To develop theories based on quantitative studies of conversational development, we need (i) data recorded in naturalistic contexts (e.g., child-caregiver dyads talking in their daily environment) where children are more likely to show much of their conversational competencies, as opposed to controlled laboratory contexts which typically involve talking to a stranger (e.g., the experimenter); (ii) data that allows for clear access to children's multimodal behavior in face-to-face conversations; and (iii) data whose acquisition method is cost-effective with the potential of being deployed at a large scale to capture individual and cultural variability. The current work is a first step to achieving this goal. We built a corpus of video chats involving children in middle childhood (6–12 years old) and their caregivers using a weakly structured word-guessing game to prompt spontaneous conversation. The manual annotations of these recordings have shown a similarity in the frequency distribution of multimodal communicative signals from both children and caregivers. As a case study, we capitalize on this rich behavioral data to study how verbal and non-verbal cues contribute to the children's conversational coordination. In particular, we looked at how children learn to engage in coordinated conversations, not only as speakers but also as listeners, by analyzing children's use of backchannel signaling (e.g., verbal “mh” or head nods) during these conversations. Contrary to results from previous in-lab studies, our use of a more spontaneous conversational setting (as well as more adequate controls) revealed that school-age children are strikingly close to adult-level mastery in many measures of backchanneling. Our work demonstrates the usefulness of recent technology in video calling for acquiring quality data that can be used for research on children's conversational development in the wild.

This article describes a pilot French/English contrastive study of some peripheral expressions. A “peripheral expression” is understood as one which occurs at the beginning (“left-peripheral” (LP)) or at the end (“right-peripheral” (RP)) of an utterance which acts as its host and over which it has scope. (The nature of the formal link between the peripheral expression and its host is left open for the purposes of this article.) These peripheral slots are prime sites for the expression of speaker stance towards the idea expressed by the host unit, and for the expression of coherence relations between the idea in the host clause and the previous idea(s). They harbour a wide range of adverbial connectors, discourse particles and comment clauses. The pilot study establishes a basic framework, within a broadly functional approach, for the identification and analysis of peripherals that can serve for contrastive study of French and English. Within the framework, the study has two main goals. One is to test whether and how, for French and/or for English expressions that can occur at either periphery, position correlates with other features of the expressions in context: function, prosodic pattern, information status and syntactic status of the host (and potentially other features of the co-text); in particular, the aim is to discover, if position is not random, what the main motivations appear to be in each case. The other main goal, and the focus of this article, is contrastive: to examine the frequencies and distributions, based on the feature analysis, of comparable peripheral expressions across French and English, to identify what generalizations, if any, can be made across the two languages. Interspeaker variation is also monitored. The primary variables here are position (right vs. left) and language (French vs. English).Recent interest in the peripheries has focused on four main issues: defining the peripheries, including devising a model of syntax that adequately accounts for peripheral expressions; determining the order of expressions, where a periphery contains several; tracing the emergence of peripheral expressions through language change; and identifying potential correlations between position and function. The first two issues have been addressed in formal linguistics, where a cartographic model of the syntactic structure of the periphery has been developed (e.g. Speas & Tenny 2003; Haegeman & Hill 2013; Rizzi & Cinque 2016). Functional and cognitive linguists until recently tended to ignore the syntactic status of peripheral elements like discourse particles and connectors, which were often claimed to be “outside” of syntax (e.g. Kaltenböck et al. 2016; Brinton 2017). Some scholars identify clause-initial pragmatic-marker “slots” (e.g. Aijmer 1996). Others posit a special “discourse grammar” distinct from “sentence grammar” (e.g. Heine et al. 2013, Fernandez Vest 2015). It has also been suggested, for English, that RP particles now constitute a formal paradigm (Haselow 2013). Overall, the third and fourth issues have received greater attention. Diachronically, in European languages investigated so far, RP appears to be a relatively recent development that can be viewed as “further grammaticalization” (almost all forms occurring at RP occur also, and occurred earlier, in other positions). The potentially different synchronic functions linked to LP and RP have mainly been investigated from the pragmatic and discourse-analytic perspectives. One widely-cited hypothesis is that the LP is specialized for subjectivity (speaker stance), while the RP is specialized for intersubjectivity (speaker-hearer relations) (e.g. Degand and Fagard 2011; Beeching and Detges 2014a). Subsequent work across languages has been inconclusive, providing moderate support for this hypothesis along with some counter-evidence (Traugott 2012). Where peripheral expressions are connective, it has been suggested for English that at RP their main function is retrospective connectivity (Haselow 2012), tying the host closely to the previous idea and/or modifying the modal or illocutionary force of the previous idea, while at LP they express interpropositional relations more loosely and can scope over longer stretches of discourse. But little attention has been paid to the role of particles at either periphery in signalling prominence relations and information structure, and relatively few studies have focused on prosodic features (v. Wichmann 2001; Bertrand and Chanet 2005; Dehé and Wichmann 2010; Romero Trillo 2018). Discourse particles, especially at LP, are often assumed to have “comma intonation”, but this assumption rests on insufficient evidence and contradictory claims are found. English final particles, it is claimed, are prosodically integrated (Haselow 2016). Although work in different language varieties has started to clarify some of these issues, few constrastive-linguistic studies have so far been carried out. For this article the peripheral expressions chosen were French alors and English then. Both expressions have developed from their lexical roots into modal adverbs and then discourse particles and/or connectives. Alors and then are both temporal adverbs that have developed very similar non-temporal polysemies. And, relevantly for this study, both now occur as discourse particles of various kinds at both the left and the right peripheries. This corpus-based study first describes a pilot methodology for the contrastive analysis. Data sources are comparable selections of dialogue from spoken-language corpora. Occurrences (and their co-text) are coded for position and on the four parameters listed above (function, prosody, information structure, syntax). The data set is too small for extrapolation, but the study suggests differences in frequency, distribution and usage across the two languages for the comparable genres. It also suggests increased divergence between alors and then for the more abstract and interactional uses. The results of this pilot study can be used to refine the approach in preparation for further work on peripheral expressions"tandis qu’à la PD based on larger corpora.

This chapter deals with the linguistic manifestations of conversation. For a long time, linguists have been interested in the levels of oral language (phonology, lexicon, syntax, discourse) separately, particularly based on prepared and non-interactive speech corpora. Research on conversational speech highlights what modern linguistic theories seek to integrate: the interdependence of these dimensions. Moreover, beyond the description of variants, this work allows us to study in a specific way the processes of language production and comprehension, including by considering them jointly, by relying on the most recent theories of interaction.In this chapter, we propose to first discuss the particularities of conversational language and their impact on the units and phenomena generally studied by linguists: phonemes, morphemes, syntagms, prosodic units, propositions, discourse units. These particularities stem from common parameters to most conversational communication situations: temporal pressure, co-presence of participants, fleeting nature of these conversational productions whose form is forgotten as soon as the message has been transmitted. Temporal pressure provides strong characteristics to conversational language linked to time management (lexical and phonetic reductions, disfluencies, etc.). The transience of productions allows the use of particular strategies (repetitions, redundancies, reformulations) which are generally avoided in other language uses. Finally, co-presence allows the use of all the modalities involved in an interaction, and on which the multiple mechanisms of alignment between participants are based. Moreover, the study of these particularities is profoundly impacted by the notions of context and shared knowledge that underlie an interaction. All these particularities due to conversational language suggest adjustments at all levels of production, but in a specific way for each of them. These adjustments are not always described at each level, but even more so, they are rarely analysed together. An important point is to put into perspective the different types of linguistic modifications linked to conversation.Moreover, understanding these general issues requires a precise description of conversation phenomena (cf. conversational analysis and interactional linguistics). These phenomena include turns of speech, listening signals and conversational feedback, or co-produced utterances.These specific phenomena of conversation must be put into perspective with the question of the interaction existing between units. We know, for example, that phonetic reductions more specifically affect sequences with a low semantic and informational load. It is therefore necessary to describe the conditions under which these interactions are possible. In particular, it is necessary to explain them by putting them in perspective with the question of comprehension.The participants in a conversation seek to achieve goals that are external to the communicative activity, but which involve the achievement of these participants’ communicative goals. In order to achieve these goals, the participants must articulate informative elements through the traditionally studied structures of language which allow the construction and articulation of representations. Conversation is a privileged place to observe these phenomena. Interactions between participants are generally built on an exchange of information. This is not a fixed mechanism as linguistics has long explained. It can be based on very superficial processing during which each participant produces and perceives bits of information. The way in which these are aggregated during a conversation is probably not always based on a compositional process, but rather consists in allowing all participants to construct a shared body of knowledge. In this chapter, we will describe the observable evidence of this mechanism, addressing in particular the question of the alignment of linguistic units that we observe during a conversation. This approach to interaction provides a theoretical framework for explaining the conversational phenomena mentioned above.This chapter will be structured as follows: 1/ conversation will be discussed as the articulation between representation and communication through language as a social action; 2/ a second part will aim at drawing up an inventory of the “traces” of the activity of conversation (communicative goal, temporal pressure, co-presence, cognitive load, social pressure) on the different linguistic units (phonemes, lexicon, syntax, prosody); 3/ we will then address the phenomena specific to conversation which are not identifiable in other types of speech (speech turns, disfluencies, conversational feedback, co-produced utterances, non-phrastic utterances, non-lexical utterances, etc.)); 4/ we will finally develop some perspectives related to all these works.

Studies of children's language use in the wild (e.g., in the context of child-caregiver social interaction) have been slowed by the time- and resource- consuming task of hand annotating utterances for communicative intents/speech acts. Existing studies have typically focused on investigating rather small samples of children, raising the question of how their findings generalize both to larger and more representative populations and to a richer set of interaction contexts. Here we propose a simple automatic model for speech act labeling in early childhood based on the INCA-A coding scheme (Ninio, Snow, Pan, & Rollins, 1994).. After validating the model against ground truth labels, we automatically annotated the entire English-language data from the CHILDES corpus. The major theoretical result was that earlier findings generalize quite well at a large scale. Further, we introduced two complementary measures for the age of acquisition of speech acts which allows us to rank different speech acts according to their order of emergence in production and comprehension.Our model will be shared with the community so that researchers can use it with their data to investigate various question related to language use both in typical and atypical populations of children.

In many areas of the world, maintaining grapevine production will require adaptation to climate change. While rigorous evaluations of adaptation strategies provide decision makers with valuable insights, those that are published often overlook major constraints, ignore local adaptive capacity, and suffer from a compartmentalization of disciplines and scales. The objective of our study was to identify current knowledge of evaluation methods and their limitations, reported in the literature. We reviewed 111 papers that evaluate adaptation strategies in the main vineyards worldwide. Evaluation approaches are analyzed through key features (e.g., climate data sources, methodology, evaluation criteria) to discuss their ability to address climate change issues, and to identify promising outcomes for climate change adaptations. We highlight the fact that combining adaptation levers in the short and long term (location, vine training, irrigation, soil, and canopy management, etc.) enables local compromises to be reached between future water availability and grapevine productivity. The main findings of the paper are three-fold: (1) the evaluation of a combination of adaptation strategies provides better solutions for adapting to climate change; (2) multi-scale studies allow local constraints and opportunities to be considered; and (3) only a small number of studies have developed multi-scale and multi-lever approaches to quantify feasibility and effectiveness of adaptation. In addition, we found that climate data sources were not systematically clearly presented, and that climate uncertainty was hardly accounted for. Moreover, only a small number of studies have assessed the economic impacts of adaptation, especially at farm scale. We conclude that the development of methodologies to evaluate adaptation strategies, considering both complementary adaptations and scales, is essential if relevant information is to be provided to the decision-makers of the wine industry.

There is a strong need for long term observations of land surface fluxes such as actual evapotranspiration (ETa). Eddy covariance (EC) method is widely used to provide ETa measurements, and several gap-filling methods have been proposed to complete inherent missing data. However, implementing gap-filling methods is questionable for EC time series collected within hilly agricultural areas at the watershed extent. Indeed, changes in wind direction induce changes in airflow inclination and footprint, and therefore possibly induce changes in the relationships on which rely gap-filling methods. This study aimed to obtain continuous ETa time series by adapting gap-filling methods to the particular conditions abovementioned. The experiment took place within an agricultural watershed in north-eastern Tunisia. A 9.6-m-high EC flux tower has been operating close to the watershed center since 2010. The sensible and latent heat fluxes data collected from 2010 to 2013 were quality controlled, and the REddyProc software was used to fill gaps at the hourly timescale. Adapting REddyProc method consisted of splitting the dataset according to wind direction, which improved the flux data at the hourly timescale, but not at the daily and monthly timescales. Finally, complete time series permitted to analyze seasonal and inter-annual variability of ETa.

There is a strong need for long term observations of land surface fluxes, especially the latent heat flux (λE), or actual evapotranspiration (ETa), a key component of both the surface energy balance and the hydrological cycle. The eddy covariance (EC) method is widely used to provide measurements of land surface fluxes. However, missing data are inherent to EC measurements and several gap-filling methods have been proposed. Nevertheless, observing ETa by EC and testing gap-filling methods in hilly watersheds received little attention. This study aimed at obtaining continuous ETa time series from EC measurements collected within a small hilly watershed, which implied adapting gap-filling techniques to these particular conditions. The experiment took place within the agricultural watershed Kamech (Northeast Tunisia) which belongs to the OMERE environmental observatory. A 9.6-m-high EC flux tower was installed in the center of the 2.45 km2 area watershed. Sensible and latent heat fluxes data collected from 2010 to 2013 were quality controlled. The software REddyProc was used to gap-fill the fluxes at hourly timescale. To account for the combined effects of wind direction and topography, REddyProc was applied after separating the two dominant wind directions, which notably improved the estimated fluxes. Aggregating the hourly λE estimates at daily and monthly timescales allowed analyzing the temporal variability of ETa over the seasons and between years.

Little attention has been devoted to interleaved discourse structures despite the challenges they offer to discourse coherence studies. Interleaved structures occur frequently if several dimensions of discourse coherence (semantic, intentional, textual, etc.) are considered simultaneously on relatively large texts. Two-step enumerative structures, a kind of interleaved structure, are enumerative structures in which the items are further developed in an enumerative fashion. We propose in this paper a treatment of the semantic and textual dimensions of such structures. We also propose some generalizations for the treatment of interleaved structures.

Backgrounding relations play a crucial role in discourse and occur frequently in both written and oral corpora. These relations come in two flavors: either the background is introduced after or before the foreground (respectively Backgroundbackwardand Backgroundforward). In Segmented Discourse Representation Theory or SDRT (Asher, Lascarides, 2003), backgrounding relations were among the first to be considered (Lascarides, Asher, 1993). However, while (Vieu, Prévot, 2004) have recently done a careful study of Backgroundbackwardon the whole much less attention has been dedicated to Backgroundforwardsituations. Our approach for Backgroundforwardbuilds on the SDRT analysis of locative adverbials in IP-adjunct position proposed in (Vieu et al., 2005). Such locative adverbials, which have the ability to locate not only the sentence but a whole segment, introduce a complex discourse structure. In a nutshell, this structure contains a new discourse topic (framing topic), which is elaborated by the constituent representing the sentence or the discourse segment falling intuitively under the scope of the adverbial. We propose in this paper to use this mechanism to treat in a uniform way a wide range of phenomena that raise difficulties for a coherent and general treatment of Backgroundforwardconfigurations.