Research

In our target article (Chow, W., Smith, C., Lau, E., & Phillips, C. (2015)), A “bag-of-arguments” mechanism for initial verb predictions, we investigated the predictions that comprehenders initially make about an upcoming verb as they read and provided evidence that they are sensitive to the arguments’ lexical meaning but not their structural roles. Here we synthesise findings from our work with other studies that show that verb predictions are sensitive to the arguments’ roles if more time is available for prediction. We content that prediction involves computations that may require differing amounts of time. Further, we argue that prediction can be usefully framed as a memory retrieval problem, linking prediction to independently wellunderstood memory mechanisms in language processing. We suggest that the delayed impact of argument roles on verb predictions may reflect a mismatch between the format of linguistic cues and target event memories. We clarify points of agreement and disagreement with the commentaries, and explain why memory access mechanisms can account for the time course of prediction.

This article investigates infant comprehension of filler-gap dependencies. Three experiments probe 15- and 20-month-olds’ comprehension of two filler-gap dependencies: wh-questions and relative clauses. Experiment 1 shows that both age groups appear to comprehend wh-questions. Experiment 2 shows that only the younger infants appear to comprehend relative clauses, while Experiment 3 shows that when parsing demands are reduced, older children can comprehend them as well. We argue that this discontinuous pattern follows from an offset in the development of grammatical knowledge and the deployment mechanisms for using that knowledge in real time. Fifteen-month-olds, we argue, lack the grammatical representation of filler-gap dependencies but are able to achieve correct performance in the task by using argument structure information. Twenty-month-olds do represent filler-gap dependencies but are inefficient in deploying those representations in real time.

Research on the neural organization of syntax – the core structure-building component of language – has focused on Broca’s area and the anterior temporal lobe (ATL) as the chief candidates for syntactic processing. However, these proposals have received considerable challenges. In order to better understand the neural basis of syntactic processing, we performed a functional magnetic resonance imaging experiment using a constrained sentence production task. We examined the BOLD response to sentence production for active and passive sentences, unstructured word lists, and syntactic perturbation. Perturbation involved cued restructuring of the planned syntax of a sentence mid utterance. Perturbation was designed to capture the effects of syntactic violations previously studied in sentence comprehension. Our experiment showed that Broca’s area and the ATL did not exhibit response profiles consistent with syntactic operations – we found no increase of activation in these areas for sentences > lists or for perturbation. Syntactic perturbation activated a cortical-subcortical network including robust activation of the right inferior frontal gyrus (RIFG). This network is similar to one previously shown to be involved in motor response inhibition. We hypothesize that RIFG activation in our study and in previous studies of sentence comprehension is due to an inhibition mechanism that may facilitate efficient syntactic restructuring.

A fundamental question in the study of human language acquisition centers around apportioning explanatory force between the experience of the learner and the core knowledge that allows learners to represent that experience. We provide a previously unidentified kind of data identifying children’s contribution to language acquisition. We identify one aspect of grammar that varies unpredictably across a population of speakers of what is ostensibly a single language. We further demonstrate that the grammatical knowledge of parents and their children is independent. The combination of unpredictable variation and parent–child independence suggests that the relevant structural feature is supplied by each learner independent of experience with the language. This structural feature is abstract because it controls variation in more than one construction. The particular case we examine is the position of the verb in the clause structure of Korean. Because Korean is a head-final language, evidence for the syntactic position of the verb is both rare and indirect. We show that (i) Korean speakers exhibit substantial variability regarding this aspect of the grammar, (ii) this variability is attested between speakers but not within a speaker, (iii) this variability controls interpretation in two surface constructions, and (iv) it is independent in parents and children. According to our findings, when the exposure language is compatible with multiple grammars, learners acquire a single systematic grammar. Our observation that children and their parents vary independently suggests that the choice of grammar is driven in part by a process operating internal to individual learners.

Acquiring the correct meanings of words expressing quantities (seven, most) and qualities (red, spotty) present a challenge to learners. Understanding how children succeed at this requires understanding, not only of what kinds of data are available to them, but also the biases and expectations they bring to the learning task. The results of our word-learning task with 4-year-olds indicate that a “syntactic bootstrapping” hypothesis correctly predicts a bias toward quantity-based interpretations when a novel word appears in the syntactic position of a determiner but also leaves open the explanation of a bias towards quality-based interpretations when the same word is presented in the syntactic position of an adjective. We develop four computational models that differentially encode how lexical, conceptual, and perceptual factors could generate the latter bias. Simulation results suggest it results from a combination of lexical bias and perceptual encoding.

What structural properties do language and music share? Although early speculation identified a wide variety of possibilities, the literature has largely focused on the parallels between musical structure and syntactic structure. Here, we argue that parallels between musical structure and prosodic structure deserve more attention. We review the evidence for a link between musical and prosodic structure and find it to be strong. In fact, certain elements of prosodic structure may provide a parsimonious comparison with musical structure without sacrificing empirical findings related to the parallels between language and music. We then develop several predictions related to such a hypothesis.

Language processing research is changing in two ways that should make it more relevant to the study of grammatical learning. First, grammatical phenomena are re-entering the psycholinguistic fray, and we have learned a lot in recent yearsabout the real-time deployment of grammatical knowledge. Second, psycholinguistics is reaching more diverse populations, leading to much research on language processing in child and adult learners. We discuss three ways that language processing can be used to understand language acquisition. Level 1 approaches (“Processing in learners”) explore well-known phenomena from the adult psycholinguistic literature and document how they play out in learner populations (child learners, adult learners, bilinguals). Level 2 approaches (“Learning effects as processing effects”) use insights from adult psycholinguistics to understand the language proficiency of learners. We argue that a rich body of findings that have been attributed to the grammatical development of anaphora should instead be attributed to limitations in the learner’s language processing system. Level 3 approaches (“Explaining learning via processing”) use language processing to understand what it takes to successfully master the grammar of a language, and why different learner groups are more or less successful. We examine whether language processing may explain why some grammatical phenomena are mastered late in children but not in adult learners. We discuss the idea that children’s language learning prowess is directly caused by their processing limitations (‘less is more’: Newport, 1990). We conclude that the idea is unlikely to be correct in its original form, but that a variant of the idea has some promise (‘less is eventually more’). We lay out key research questions that need to be addressed in order to resolve the issues addressed in the paper.

Lara Ehrenhofer and Colin Phillips respond to commentary on their discussion of how development in the capacity to parse speech online relates to grammar acquisition in young children.

Sentences such as “The ship was sunk to collect the insurance” exhibit an unusual form of anaphora, implicit control, where neither anaphor nor antecedent is audible. The non-finite reason clause has an understood subject, PRO, that is anaphoric; here it may be understood as naming the agent of the event of the host clause. Yet since the host is a short passive, this agent is realized by no audible dependent. The putative antecedent to PRO is therefore implicit, which it normally cannot be. What sorts of representations subserve the comprehension of this dependency? Here we present four self-paced reading time studies directed at this question. Previous work showed no processing cost for implicit vs. explicit control, and took this to support the view that PRO is linked syntactically to a silent argument in the passive. We challenge this conclusion by reporting that we also find no processing cost for remote implicit control, as in: “The ship was sunk. The reason was to collect the insurance.” Here the dependency crosses two independent sentences, and so cannot, we argue, be mediated by syntax. Our Experiments 1–4 examined the processing of both implicit (short passive) and explicit (active or long passive) control in both local and remote configurations. Experiments 3 and 4 added either “3 days ago” or “just in order” to the local conditions, to control for the distance between the passive and infinitival verbs, and for the predictability of the reason clause, respectively. We replicate the finding that implicit control does not imposean additional processing cost . But critically we show that remote control does not impose a processing cost either. Reading times at the reason clause were never slower when control was remote. In fact they were always faster. Thus, efficient processing of local implicit control cannot show that implicit control is mediated by syntax; nor, in turn, that there is a silent but grammatically active argument in passives.

This paper investigates the geometry of phi-features, with a special emphasis on number and gender in Spanish. We address two sets of questions: (i) are number and gender bundled together or do they constitute separate categories, and (ii) does the internal feature composition of number and gender follow a single- or a multi-valued system? Given the lack of consensus on these issues based on primary data, we approach these questions experimentally, using the phenomenon of agreement attraction: a situation in which ungrammatical sequences are perceived as grammatical when one of the NPs is erroneously identified as determining agreement. Our results offer novel support in favor of an agreement model in which number and gender are in separate projections and are valued independently. In addition, our results indicate that number but not gender in Spanish is multi-valued.