Publications

Abstract

A foundational assumption of human communication is that speakers should say as much as necessary, but no more. Yet, people routinely produce redundant adjectives and their propensity to do so varies cross-linguistically. Here, we propose a computational theory, whereby speakers create referential expressions designed to facilitate listeners’ reference resolution, as they process words in real time. We present a computational model of our account, the Incremental Collaborative Efficiency (ICE) model, which generates referential expressions by considering listeners’ real-time incremental processing and reference identification. We apply the ICE framework to physical reference, showing that listeners construct expressions designed to minimize listeners’ expected visual search effort during online language processing. Our model captures a number of known effects in the literature, including cross-linguistic differences in speakers’ propensity to over-specify. Moreover, the ICE model predicts graded acceptability judgments with quantitative accuracy, systematically outperforming an alternative, brevity-based model. Our findings suggest that physical reference production is best understood as driven by a collaborative goal to help the listener identify the intended referent, rather than by an egocentric effort to minimize utterance length.

Abstract

When people hear words for objects with prototypical colors (e.g., ‘banana’), they look at objects of the same color (e.g., lemon), suggesting a link in comprehension between objects and their prototypical colors. However, that link does not carry over to production: The experimental record also shows that when people speak, they tend to omit prototypical colors, using color adjectives when it is informative (e.g., when referring to clothes, which have no prototypical color). These findings yield an interesting prediction, which we tested here: while prior work shows that people look at yellow objects when hearing ‘banana’, they should look away from bananas when hearing ‘yellow’. The results of an offline sentence-completion task (N = 100) and an online eye-tracking task (N = 41) confirmed that when presented with truncated color descriptions (e.g., ‘Click on the yellow…’), people anticipate clothing items rather than stereotypical fruits. A corpus analysis ruled out the possibility that this association between color and clothing arises from simple context-free co-occurrence statistics. We conclude that comprehenders make linguistic predictions based not only on what they know about the world (e.g., which objects are yellow) but also on what speakers tend to say about the world (i.e., what content would be informative).

Abstract

In the Dot task, children and adults involuntarily compute an avatar’s visual perspective, which has been interpreted by some as automatic Theory of Mind. This interpretation has been challenged by other researchers arguing that the task reveals automatic attentional orienting. Here we tested a new interpretation of previous findings: the seemingly automatic processes revealed by the Dot task result from the high Executive Control demands of this verification paradigm, which taxes short-term memory and imposes perspective-switching costs. We tested this hypothesis in three experiments conducted in India with newly sighted children (Experiment 1; N = 5; all girls), neurotypical children (Experiment 2; ages 5–10; N = 90; 38 girls) and adults (Experiment 3; N = 30; 18 women) in a highly simplified version of the Dot task. No evidence of automatic perspective-taking was observed, although all groups revealed perspective-taking costs. A newly sighted child and the youngest children in our sample also showed an egocentric bias, which disappeared by age 10, confirming that visual perspective taking develops during the school years. We conclude that the standard Dot task imposes such methodological demands on both children and adults that the alleged evidence of automatic processes (either mindreading or domain general) may simply reveal limitations in Executive Control.

Abstract

In referential communication, gaze is often interpreted as a social cue that facilitates comprehension and enables word learning. Here we investigated the degree to which head turning facilitates gaze following. We presented participants with static pictures of a man looking at a target object in a first and third block of trials (pre- and post-intervention), while they saw short videos of the same man turning towards the target in the second block of trials (intervention). In Experiment 1, newly sighted individuals (treated for congenital cataracts; N = 8) benefited from the motion cues, both when comparing their initial performance with static gaze cues to their performance with dynamic head turning, and their performance with static cues before and after the videos. In Experiment 2, neurotypical school children (ages 5–10 years; N = 90) and adults (N = 30) also revealed improved performance with motion cues, although most participants had started to follow the static gaze cues before they saw the videos. Our results confirm that head turning is an effective social cue when interpreting new words, offering new insights for a pathways approach to development.

Abstract

Previous research has pointed at communicative efficiency as a possible constraint on language structure. Here we investigated adjective position in American Sign Language (ASL), a language with relatively flexible word order, to test the incremental efficiency hypothesis, according to which both speakers and signers try to produce efficient referential expressions that are sensitive to the word order of their languages. The results of three experiments using a standard referential communication task confirmed that deaf ASL signers tend to produce absolute adjectives, such as color or material, in prenominal position, while scalar adjectives tend to be produced in prenominal position when expressed as lexical signs, but in postnominal position when expressed as classifiers. Age of ASL exposure also had an effect on referential choice, with early-exposed signers producing more classifiers than late-exposed signers, in some cases. Overall, our results suggest that linguistic, pragmatic and developmental factors affect referential choice in ASL, supporting the hypothesis that communicative efficiency is an important factor in shaping language structure and use.

Abstract

This study explores the connection between language and social cognition by empirically testing different typological analyses of various demonstrative systems. Linguistic typology classifies demonstrative systems as distance-oriented or person-oriented, depending on whether they indicate the location of a referent relative only to the speaker, or to both the speaker and the listener. From the perspective of social cognition, speakers of languages with person-oriented systems must monitor their listener’s spatial location in order to accurately use their demonstratives, while speakers of languages with distance-oriented systems can use demonstratives from their own, egocentric perspective. Resolving an ongoing controversy around the nature of the Spanish demonstrative system, the results of Experiment 1 confirmed that this demonstrative system is person oriented, while the English system is distance oriented. Experiment 2 revealed that not all three-way demonstrative systems are person oriented, with Japanese speakers showing sensitivity to the listener’s spatial location, while Turkish speakers did not show such an effect in their demonstrative choice. In Experiment 3, Catalan-Spanish bilinguals showed sensitivity to listener position in their choice of the Spanish distal form, but not in their choice of the medial form. These results were interpreted as a transfer effect from Catalan, which revealed analogous results to English. Experiment 4 investigated the use of demonstratives to redirect a listener’s attention to the intended referent, which is a universal function of demonstratives that also hinges on social cognition. Japanese and Spanish speakers chose between their proximal and distal demonstratives flexibly, depending on whether the listener was looking closer or further from the referent, whereas Turkish speakers chose their medial form for attention correction. In conclusion, the results of this study support the view that investigating how speakers of different languages jointly use language and social cognition in communication has the potential to unravel the deep connection between these two fundamentally human capacities.

Abstract

We investigated the effect of optionality on the acquisition of new/given markers, with a special focus on grammaticalization as a stage of optional use of the emerging form. To this end, we conducted a narrative-elicitation task with 5-year-old children and adults across four typologically-distinct languages with different new/given markers: English, Hindi, Mandinka and Spanish. Our starting assumption was that the Hindi numeral ‘ek’ (one) is developing into an indefinite article, which should delay children’s acquisition because of its optional use to introduce discourse referents. Supporting the Optionality Hypothesis, Experiment 1 revealed that obligatory markers are acquired earlier than optional markers. Experiment 2 focused on Hindi and showed that 10-year-old children’s use of ‘ek’ to introduce discourse characters was higher than 5-year-olds’ and comparable to adults’, replicating this pattern of results in two different cities in Northern India. Lastly, a follow-up study showed that Mandinka-speaking children and adults made use of all available discourse markers when tested on a familiar story, rather than with pictorial prompts, highlighting the importance of using culturally-appropriate methods of narrative elicitation in cross-linguistic research. We conclude by discussing the implications of article grammaticalization for common ground management in a speech community.

Abstract

While most research on scalar implicature has focused on the lexical scale “some” vs “all,” here we investigated an understudied scale formed by two syntactic constructions: categorizations (e.g., “Wilma is a nurse”) and comparisons (“Wilma is like a nurse”). An experimental study by Rubio-Fernandez et al. (2017) showed high rates of logical responses to superordinate comparisons, even though they are underinformative when interpreted pragmatically (e.g., “A robin is like a bird” implies that a robin is not a bird). Based on recent studies on enrichment priming, we predicted that including “some” and “all” statements (which typically elicit high rates of pragmatic responses) in sentence verification and sentence evaluation tasks would introduce an informativity bias, increasing pragmatic responses to superordinate comparisons. The results of three Web-based experiments supported our predictions, showing that different scalar expressions not only give rise to different rates of scalar implicatures, but can also affect the degree to which an experimental task elicits pragmatic reasoning.

Abstract

Demonstratives—simple referential devices like this and that—are linguistic universals, but their meaning varies cross-linguistically. In languages like English and Italian, demonstratives are thought to encode the referent’s distance from the producer (e.g., that one means “the one far away from me”),
while in others, like Portuguese and Spanish, they encode relative distance from both producer and receiver (e.g., aquel means “the one far away from both of us”). Here we propose that demonstratives are also sensitive to the receiver’s focus of attention, hence requiring a deeper form of social cognition
than previously thought. We provide initial empirical and computational evidence for this idea, suggesting that producers use
demonstratives to redirect the receiver’s attention towards the intended referent, rather than only to indicate its physical distance.