Hand and Mind: What Gestures Reveal about Thought. David McNeill. Chicago and London: University of Chicago Press, 1992. 416 pp.

Hand and Mind: What Gestures Reveal about Thought

Infants’ speech perception skills show a dual change towards the end of the first year of life. Not only does non-native speech perception decline, as often shown, but native language speech perception skills show improvement, reflecting a facilitative effect of experience with native language. The mechanism underlying change at this point in development, and the relationship between the change in native and non-native speech perception, is of theoretical interest. As shown in new data presented here, at the cusp of this developmental change, infants’ native and non-native phonetic perception skills predict later language ability, but in opposite directions. Better native language skill at 7.5 months of age predicts faster language advancement, whereas better non-native language skill predicts slower advancement. We suggest that native language phonetic performance is indicative of neural commitment to the native language, while non-native phonetic performance reveals uncommitted neural circuitry. This paper has three goals: (i) to review existing models of phonetic perception development, (ii) to present new event-related potential data showing that native and nonnative phonetic perception at 7.5 months of age predicts language growth over the next 2 years, and (iii) to describe a revised version of our previous model, the native language magnet model, expanded (NLM-e). NLM-e incorporates five new principles. Specific testable predictions for future research programmes are described.

/pdf/phonetic-learning-as-a-pathway-to-language-new-data-and-15t1lsqh9h.pdf

Phonetic learning as a pathway to language: new data and native language magnet theory expanded (NLM-e)

The authors examine the effects of poverty-related adversity on child development, drawing upon psychobiological principles of experiential canalization and the biological embedding of experience. They integrate findings from research on stress physiology, neurocognitive function, and self-regulation to consider adaptive processes in response to adversity as an aspect of children’s development. Recent research on early caregiving is paired with research in prevention science to provide a reorientation of thinking about the ways in which psychosocial and economic adversity are related to continuity in human development.

/pdf/child-development-in-the-context-of-adversity-experiential-5dt6znxfts.pdf

Child development in the context of adversity: experiential canalization of brain and behavior.

http://ilabs.washington.edu/sites/default/files/2010%20Kuhl.pdf

Brain mechanisms in early language acquisition.

I advance the hypothesis that the earliest phases of language acquisition ‐ the developmental transition from an initial universal state of language processing to one that is language-specific ‐ requires social interaction. Relating human language learning to a broader set of neurobiological cases of communicative development, I argue that the social brain ‘gates’ the computational mechanisms involved in human language learning.

https://courses.washington.edu/ccab/Kuhl%20-%20Is%20speech%20learning%20'gated'%20by%20social%20brain.pdf

Is speech learning ‘gated’ by the social brain?

Infants rapidly learn the sound categories of their native language, even though they do not receive explicit or focused training. Recent research suggests that this learning is due to infants' sensitivity to the distribution of speech sounds and that infant-directed speech contains the distributional information needed to form native-language vowel categories. An algorithm, based on Expectation–Maximization, is presented here for learning the categories from a sequence of vowel tokens without (i) receiving any category information with each vowel token, (ii) knowing in advance the number of categories to learn, or (iii) having access to the entire data ensemble. When exposed to vowel tokens drawn from either English or Japanese infant-directed speech, the algorithm successfully discovered the language-specific vowel categories (/i, i, e, e/ for English, /i, iː, e, eː/ for Japanese). A nonparametric version of the algorithm, closely related to neural network models based on topographic representation and competitive Hebbian learning, also was able to discover the vowel categories, albeit somewhat less reliably. These results reinforce the proposal that native-language speech categories are acquired through distributional learning and that such learning may be instantiated in a biologically plausible manner. 

language acquisition
speech perception
expectation maximization
online learning

/pdf/unsupervised-learning-of-vowel-categories-from-infant-qg9mw491x2.pdf

Unsupervised learning of vowel categories from infant-directed speech

The conventional view is that perceptual/cognitive development is an incremental process of acquisition. Several striking findings have revealed, however, that the sensitivity to non-native languages, faces, vocalizations, and music that is present early in life declines as infants acquire experience with native perceptual inputs. In the language domain, the decline in sensitivity is reflected in a process of perceptual narrowing that is thought to play a critical role during the acquisition of a native-language phonological system. Here, we provide evidence that such a decline also occurs in infant response to multisensory speech. We found that infant intersensory response to a non-native phonetic contrast narrows between 6 and 11 months of age, suggesting that the perceptual system becomes increasingly more tuned to key native-language audiovisual correspondences. Our findings lend support to the notion that perceptual narrowing is a domain-general as well as a pan-sensory developmental process.

https://www.pnas.org/content/pnas/106/26/10598.full.pdf

Narrowing of intersensory speech perception in infancy

http://www.colinphillips.net/wp-content/uploads/2015/09/werker2007.pdf

Infant-directed speech supports phonetic category learning in English and Japanese☆

Infants growing up in bilingual environments succeed at learning two languages. What adaptive processes enable them to master the more complex nature of bilingual input? One possibility is that bilingual infants take greater advantage of the redundancy of the audiovisual speech that they usually experience during social interactions. Thus, we investigated whether bilingual infants' need to keep languages apart increases their attention to the mouth as a source of redundant and reliable speech cues. We measured selective attention to talking faces in 4-, 8-, and 12-month-old Catalan and Spanish monolingual and bilingual infants. Monolinguals looked more at the eyes than the mouth at 4 months and more at the mouth than the eyes at 8 months in response to both native and nonnative speech, but they looked more at the mouth than the eyes at 12 months only in response to nonnative speech. In contrast, bilinguals looked equally at the eyes and mouth at 4 months, more at the mouth than the eyes at 8 months, and more at the mouth than the eyes at 12 months, and these patterns of responses were found for both native and nonnative speech at all ages. Thus, to support their dual-language acquisition processes, bilingual infants exploit the greater perceptual salience of redundant audiovisual speech cues at an earlier age and for a longer time than monolingual infants.

Bilingualism Modulates Infants’ Selective Attention to the Mouth of a Talking Face

Contrasting results have been reported regarding the phonetic acquisition of bilinguals. A lack of discrimination has been observed for certain native contrasts in 8-month-old Catalan-Spanish bilingual infants (Bosch & Sebastian-Galles, 2003a), though not in French-English bilingual infants (Burns, Yoshida, Hill & Werker, 2007; Sundara, Polka & Molnar, 2008). At present, the data for Catalan-Spanish bilinguals constitute an exception in the early language acquisition literature. This study contributes new findings that show that Catalan-Spanish bilingual infants do not lose the capacity to discriminate native contrasts. We used an adaptation of the anticipatory eye movement paradigm (AEM; McMurray & Aslin, 2004) to explore this question. In two experiments we tested the ability of infants from Catalan and Spanish monolingual families and from Catalan-Spanish bilingual families to discriminate a Spanish-Catalan common and a Catalan-specific vowel contrast. Results from both experiments revealed that Catalan-Spanish bilingual infants showed the same discrimination abilities as those shown by their monolingual peers, even in a phonetic contrast that had not been discriminated in previous studies. Our results demonstrate that discrimination can be observed in 8-month-old bilingual infants when tested with a measure not based on recovery of attention. The high ratio of cognates in Spanish and Catalan may underlie the reason why bilinguals failed to discriminate the native vowels when tested with the familiarization-preference procedure but succeeded with the AEM paradigm.

Ferran Pons

Papers

Unsupervised learning of vowel categories from infant-directed speech

Narrowing of intersensory speech perception in infancy

Infant-directed speech supports phonetic category learning in English and Japanese☆

Bilingualism Modulates Infants’ Selective Attention to the Mouth of a Talking Face

The acquisition of phonetic categories in bilingual infants: new data from an anticipatory eye movement paradigm