Learning speech-internal cues to pronoun interpretation from co-speech gesture: a training study.

This study explores whether children can learn a structural processing bias relevant to pronoun interpretation from brief training. Over three days, 42 five-year-olds were exposed to narratives exhibiting a first-mentioned tendency. Two characters were introduced, and the first-mentioned was later described engaging in a solo activity. In our primary condition of interest, the Gesture Training condition, the solo-activity sentence contained an ambiguous pronoun, but co-speech gesture clarified the referent. There were two comparison conditions. In the Gender Training condition the characters were different genders, thereby avoiding ambiguity. In the Name Training condition, the first-mentioned name was simply repeated. Ambiguous pronoun interpretation was tested pre- and post-training. Children in the Gesture condition were significantly more likely to interpret ambiguous pronouns as the first-mentioned character after training. Results from the comparison conditions were ambiguous: there was a small but non-significant effect of training, but also no significant differences between conditions.

Introducing the Infant Bookreading Database (IBDb).

Studies on the relationship between bookreading and language development typically lack data about which books are actually read to children. This paper reports on an Internet survey designed to address this data gap. The resulting dataset (the Infant Bookreading Database or IBDb) includes responses from 1,107 caregivers of children aged 0-36 months who answered questions about the English-language books they most commonly read to their children. The inclusion of demographic information enables analysis of subsets of data based on age, sex, or caregivers' education level. A comparison between our dataset and those used in previous analyses reveals that there is relatively little overlap between booklists gathered from proxies such as bestseller lists and the books caregivers reported reading to children in our survey. The IBDb is available for download for use by researchers at .

Children's use of gesture in ambiguous pronoun interpretation.

This study explores whether children can use gesture to inform their interpretation of ambiguous pronouns. Specifically, we ask whether four- to eight-year-old English-speaking children are sensitive to information contained in co-referential localizing gestures in video narrations. The data show that the older (7-8 years of age) but not younger (4-5 years) children integrate co-referential gestures into their interpretation of pronouns. This is the same age at which they show sensitivity to order-of-mention, the only other cue available in the stimuli. Interestingly, when children show sensitivity to the gestures, they are quite similar to adults, in that gestures consistent with order-of-mention increase first-mentioned responses as compared to stimuli with no gestures, but only slightly, while gestures inconsistent with order-of-mention have a larger effect on interpretation, decreasing first-mentioned responses and increasing second-mentioned responses.

Evaluating English-language morphological awareness assessments.

Many studies have shown that morphological knowledge has effects on reading comprehension separate from other aspects of language knowledge. This has implications for reading instruction and assessment: it suggests that children could have reading comprehension difficulties that are due to a lack of morphological knowledge, and thus, that explicit instruction of morphology might be helpful for them, indeed for all children. To find children who might especially benefit from specific instruction in morphology, we would need good tests of morphological knowledge. We evaluated a set of morphological awareness assessments to determine whether they conclusively tapped into morphological knowledge, and found that it was not possible to be certain that they were accurately targeting morphological knowledge.

The problem of conventionality in the development of creole morphological systems.

This paper focuses on the problem of the conventionalization of grammatical morphology during language formation, asking how a form comes to have a shared grammatical meaning in an emerging linguistic community. Results from an experiment, inspired by changes in the use of space in Nicaraguan Sign Language, are presented that demonstrate the difficulty of conventionalization for grammatical forms. We show that even in cases where meaning should be relatively easy to discern, adult listeners are not consistent, either internally or when compared to each other, in the inferences they draw. The paper ends with a discussion of the nature of the problem with respect to emerging languages more broadly, and speculates on how grammatical forms might come to have shared meanings in a newly emerging language, focussing on the role that children might play in the process.

Humans Rapidly Learn Grammatical Structure in a New Musical Scale.

Knowledge of musical rules and structures has been reliably demonstrated in humans of different ages, cultures, and levels of music training, and has been linked to our musical preferences. However, how humans acquire knowledge of and develop preferences for music remains unknown. The present study shows that humans rapidly develop knowledge and preferences when given limited exposure to a new musical system. Using a non-traditional, unfamiliar musical scale (Bohlen-Pierce scale), we created finite-state musical grammars from which we composed sets of melodies. After 25-30 min of passive exposure to the melodies, participants showed extensive learning as characterized by recognition, generalization, and sensitivity to the event frequencies in their given grammar, as well as increased preference for repeated melodies in the new musical system. Results provide evidence that a domain-general statistical learning mechanism may account for much of the human appreciation for music.

Co-speech gesture as input in verb learning.

People gesture a great deal when speaking, and research has shown that listeners can interpret the information contained in gesture. The current research examines whether learners can also use co-speech gesture to inform language learning. Specifically, we examine whether listeners can use information contained in an iconic gesture to assign meaning to a novel verb form. Two experiments demonstrate that adults and 2-, 3-, and 4-year-old children can infer the meaning of novel intransitive verbs from gestures when no other source of information is present. The findings support the idea that gesture might be a source of input available to language learners.

Investigating the cause of language regularization in adults: memory constraints or learning effects?

When language learners are exposed to inconsistent probabilistic grammatical patterns, they sometimes impose consistency on the language instead of learning the variation veridically. The authors hypothesized that this regularization results from problems with word retrieval rather than from learning per se. One prediction of this, that easing the demands of lexical retrieval leads to less regularization, was tested. Adult learners were exposed to a language containing inconsistent probabilistic patterns and were tested with either a standard production task or one of two tasks that reduced the demands of lexical retrieval. As predicted, participants tested with the modified tasks more closely matched the probability of the inconsistent items than did those tested with the standard task.

The curse of knowledge: first language knowledge impairs adult learners' use of novel statistics for word segmentation.

We investigated whether adult learners' knowledge of phonotactic restrictions on word forms from their first language impacts their ability to use statistical information to segment words in a novel language. Adults were exposed to a speech stream where English phonotactics and phoneme co-occurrence information conflicted. A control where these did not conflict was also run. Participants chose between words defined by novel statistics and words that are phonotactically possible in English, but had much lower phoneme contingencies. Control participants selected words defined by statistics while experimental participants did not. This result held up with increases in exposure and when segmentation was aided by telling participants a word prior to exposure. It was not the case that participants simply preferred English-sounding words, however, when the stimuli contained very short pauses, participants were able to learn the novel words despite the fact that they violated English phonotactics. Results suggest that prior linguistic knowledge can interfere with learners' abilities to segment words from running speech using purely statistical cues at initial exposure.

Why segmentation matters: Experience-driven segmentation errors impair "morpheme" learning.

We ask whether an adult learner's knowledge of their native language impedes statistical learning in a new language beyond just word segmentation (as previously shown). In particular, we examine the impact of native-language word-form phonotactics on learners' ability to segment words into their component morphemes and learn phonologically triggered variation of morphemes. We find that learning is impaired when words and component morphemes are structured to conflict with a learner's native-language phonotactic system, but not when native-language phonotactics do not conflict with morpheme boundaries in the artificial language. A learner's native-language knowledge can therefore have a cascading impact affecting word segmentation and the morphological variation that relies upon proper segmentation. These results show that getting word segmentation right early in learning is deeply important for learning other aspects of language, even those (morphology) that are known to pose a great difficulty for adult language learners.

When it hurts (and helps) to try: the role of effort in language learning.

Compared to children, adults are bad at learning language. This is counterintuitive; adults outperform children on most measures of cognition, especially those that involve effort (which continue to mature into early adulthood). The present study asks whether these mature effortful abilities interfere with language learning in adults and further, whether interference occurs equally for aspects of language that adults are good (word-segmentation) versus bad (grammar) at learning. Learners were exposed to an artificial language comprised of statistically defined words that belong to phonologically defined categories (grammar). Exposure occurred under passive or effortful conditions. Passive learners were told to listen while effortful learners were instructed to try to 1) learn the words, 2) learn the categories, or 3) learn the category-order. Effortful learners showed an advantage for learning words while passive learners showed an advantage for learning the categories. Effort can therefore hurt the learning of categories.

Learning language with the wrong neural scaffolding: the cost of neural commitment to sounds.

Does tuning to one's native language explain the "sensitive period" for language learning? We explore the idea that tuning to (or becoming more selective for) the properties of one's native-language could result in being less open (or plastic) for tuning to the properties of a new language. To explore how this might lead to the sensitive period for grammar learning, we ask if tuning to an earlier-learned aspect of language (sound structure) has an impact on the neural representation of a later-learned aspect (grammar). English-speaking adults learned one of two miniature artificial languages (MALs) over 4 days in the lab. Compared to English, both languages had novel grammar, but only one was comprised of novel sounds. After learning a language, participants were scanned while judging the grammaticality of sentences. Judgments were performed for the newly learned language and English. Learners of the similar-sounds language recruited regions that overlapped more with English. Learners of the distinct-sounds language, however, recruited the Superior Temporal Gyrus (STG) to a greater extent, which was coactive with the Inferior Frontal Gyrus (IFG). Across learners, recruitment of IFG (but not STG) predicted both learning success in tests conducted prior to the scan and grammatical judgment ability during the scan. Data suggest that adults' difficulty learning language, especially grammar, could be due, at least in part, to the neural commitments they have made to the lower level linguistic components of their native language.

The effect of sonority on word segmentation: evidence for the use of a phonological universal.

It has been well documented how language-specific cues may be used for word segmentation. Here, we investigate what role a language-independent phonological universal, the sonority sequencing principle (SSP), may also play. Participants were presented with an unsegmented speech stream with non-English word onsets that juxtaposed adherence to the SSP with transitional probabilities. Participants favored using the SSP in assessing word-hood, suggesting that the SSP represents a potentially powerful cue for word segmentation. To ensure the SSP influenced the segmentation process (i.e., during learning), we presented two additional groups of participants with either (a) no exposure to the stimuli prior to testing or (b) the same stimuli with pauses marking word breaks. The SSP did not influence test performance in either case, suggesting that the SSP is important for word segmentation during the learning process itself. Moreover, the fact that SSP-independent segmentation of the stimulus occurred (in the latter control condition) suggests that universals are best understood as biases rather than immutable constraints on learning.

More than words: Adults learn probabilities over categories and relationships between them.

This study examines whether human learners can acquire statistics over abstract categories and their relationships to each other. Adult learners were exposed to miniature artificial languages containing variation in the ordering of the Subject, Object, and Verb constituents. Different orders (e.g. SOV, VSO) occurred in the input with different frequencies, but the occurrence of one order versus another was not predictable. Importantly, the language was constructed such that participants could only match the overall input probabilities if they were tracking statistics over abstract categories, not over individual words. At test, participants reproduced the probabilities present in the input with a high degree of accuracy. Closer examination revealed that learner's were matching the probabilities associated with individual verbs rather than the category as a whole. However, individual nouns had no impact on word orders produced. Thus, participants learned the probabilities of a particular ordering of the abstract grammatical categories Subject and Object associated with each verb. Results suggest that statistical learning mechanisms are capable of tracking relationships between abstract linguistic categories in addition to individual items.