The relation between pointing and language development

The December 2010 issue of 'Developmental Review' features a nice meta-analysis of of studies on pointing and language development by Cristina Colonnesia, Geert Jan J.M. Stamsa, Irene Kostera, and Marc J. Noomb. Here's their abstract and their 'research highlights'

Abstract

The use of the pointing gesture is one of the first ways to communicate with the world. This gesture emerges before the second year of life and it is assumed to be the first form of intentional communication. This meta-analysis examined the concurrent and longitudinal relation between pointing and the emergence of language. Twenty-five studies were included into the meta-analysis, including 734 children. The role of several moderators was examined: pointing modality, pointing motive, age at which the pointing was measured, the assessment method of the pointing gesture and language development, the modality of language, SES, and country. The results showed both a concurrent (r = .52) and a longitudinal (r = .35) relation between pointing and language development.

The relation between pointing and language development became stronger with age, and was found for pointing with a declarative and general motive, but not for pointing with an imperative motive. It is concluded that the pointing gesture is a key joint-attention behavior involved in the acquisition of language.

Research highlights

► Pointing gesture is concurrently (r = .52) and longitudinally (r = .35) related to language development. ► The relation between pointing gesture and language becomes stronger with age, in particular during the end of the second year of life. ► Both the production (r = .33) and the comprehension (r = .38) of pointing gesture are related to language development. ► Pointing with a declarative (r = .39) and with a general motive (r = .39), rather than with an imperative motive (r = .04), are related to language.

The need for multimodality in primate communication research

Barbara King points to a very interesting article in press at Animal Behaviour. In their essay "The language void: the need for multimodality in primate communication research" Katie Slocombe, Bridget Waller and Katja Liebal analyse more than 550 studies on primate communication from 1960 to 2008 and argue that research in one modality (e.g. gesture) often differs so strongly in its methodology from research on another modality (e.g. alarm calls) that the results can hardly be reliably compared. Here's their abstract:

Theories of language evolution often draw heavily on comparative evidence of the communicative abilities of extant nonhuman primates (primates). Many theories have argued exclusively for a unimodal origin of language, usually gestural or vocal. Theories are often strengthened by research on primates that indicates the absence of certain linguistic precursors in the opposing communicative modality. However, a systematic review of the primate communication literature reveals that vocal, gestural and facial signals have attracted differing theoretical and methodological approaches, rendering cross-modal comparisons problematic. The validity of the theories based on such comparisons can therefore be questioned. We propose that these a priori biases, inherent in unimodal research, highlight the need for integrated multimodal research. By examining communicative signals in concert we can both avoid methodological discontinuities as well as better understand the phylogenetic precursors to human language as part of a multimodal system.

Barbara King's discussion of the article is also very illuminating.

John Hawks: How language eats brains, and why it matters to language evolution.

John Hawks has posted a fascinating discussion of a new paper published in the Proceedings of the National Academy of Sciences (here) by Bedny et al. that shows that in congenitally blind adults, "brain regions that are thought to have evolved for vision can take on language processing as a result of early experience." (to quote from the abstract) (see also John Lehrer's discussion, here)

These results show the brain's immense plasticity, especially in early development. Crucially, the fact that "brain regions that did not evolve for language can nevertheless participate in language processing" (Bedny et al.) poses the questions whether language-specific processing functions need to have evolved at all.

To quote from John Hawk's discussion at lenght:

"The blind subjects tell us that the ground for language processing is almost as fertile elsewhere in the cortex. Many brain areas have the genetic equipment to recruit and organize neurons into useful circuits for language processing. Language development is developmentally robust because it can rely on a rich language environment, not because of genetic standardization. The basic problems of language evolution must be explained by showing how robust language communities emerged. I don't preclude genetics, far from it -- weaker language environments may have become stronger because of evolutionary change. But that evolution must have been substantially domain-general, because language processing is not specifically canalized by genetics.

I like this scenario because it means we shouldn't be looking for lots of language-specific genetic changes in the last few hundred thousand years. The Neandertal genome suggests that there may not have been any at all"

To me, these results also seem compatible with arguments made by Morten Christiansen, Nick Chater, and others, who argue that language was shaped by the human brain and its learning and processing mechanisms, instead of there being a language-specific biological endowment. On this view, then "language evolution is a process of cultural change, in which linguistic structures are shaped through repeated cycles of learning and use by domain-general mechanisms" (Chater & Christiansen 2010).

UPDATE [21/03/11]: John Hawks has written another highly interesting post that is also relevant to this topic and the question of the evolution of language and cognition more generally: The development of sharing and cooperation from infancy to school-age and (here).

The Linguistics of Birdsong - Review in Trends in Cognitive Sciences

In the current issue of Trends in Cognitive Sciences there is an interesting (and free!) review of the linguistics of birdsong and its similarities and differences to human language:

Unlike our primate cousins, many species of bird share with humans a capacity for vocal learning, a crucial factor in speech acquisition. There are striking behavioural, neural and genetic similarities between auditory-vocal learning in birds and human infants. Recently, the linguistic parallels between birdsong and spoken language have begun to be investigated. Although both birdsong and human language are hierarchically organized according to particular syntactic constraints, birdsong structure is best characterized as ‘phonological syntax’, resembling aspects of human sound structure. Crucially, birdsong lacks semantics and words. Formal language and linguistic analysis remains essential for the proper characterization of birdsong as a model system for human speech and language, and for the study of the brain and cognition evolution.

Robert C. Berwick, Kazuo Okanoya, Gabriel J.L. Beckers and Johan J. Bolhuis (2011) "Songs to syntax: the linguistics of birdsong." In: Trends in Cognitive Sciences." Volume 15, Issue 3, March 2011, Pages 113-121

Update: Edmund Blair Bolles of Babel's Dawn has also just published a very short article about human speech, birdsong and convergent evolution in the journal Bioscience (here)

Four Stone Hearth 112, Chimpanzees, Hosts, and Goats

The latest edition of the Four Stone Hearth #112 is out over at Anthropology in Practice and contains a number of very interesting links.

For example, they link to a very interesting post by Barbara J. King in which she discusses work by David Leavens, Timothy P. Racine, and William D. Hopkins about pointing behaviour in chimpanzees. These authors question claims made by people like Michael Tomasello and others that only humans point declaratively to provide information and share attention (something which I blogged about previously, e.g. here; see also this post and a very interesting post about a new article by Hopkins and colleagues at Babel's Dawn)

Also, Four Stone Hearth is in dire need of hosts so please check out its announcement page if you might be interested in hosting it.

Hat tip: Daniel Lende

P.S. on a lighter note Anthropologists Trace Human Origins Back To One Large Goat

Patricia Kuhl: The linguistic genius of babies | Video on TED.com

Patricia Kuhl: The linguistic genius of babies | Video on TED.com

"At TEDxRainier, Patricia Kuhl shares astonishing findings about how babies learn one language over another -- by listening to the humans around them and "taking statistics" on the sounds they need to know. Clever lab experiments (and brain scans) show how 6-month-old babies use sophisticated reasoning to understand their world."

Can children learn abstract syntactic principles by using general cognitive capacities?

One of the most hotly debated issues in the study of language acquisition is whether the abstract syntactic principles of a language can be learned by children

1. by using domain-general capacities (such as pattern finding, analogy, statistical learning, categorization and generalization, etc.)

or whether they need

2. innately specified knowledge of language that enables them to form the right abstract syntactic categories that cannot be infered from the surface level of linguistic utterances (Chomsky's Poverty of Stimulus Argument)

In a new paper in the journal Cognition, Perfors et al. (2011) argue that domain-general capacities are sufficient for children to be able to learn abstract syntactic principles inherent in the linguistic input.

Here's the abstract:

Children acquiring language infer the correct form of syntactic constructions for which they appear to have little or no direct evidence, avoiding simple but incorrect generalizations that would be consistent with the data they receive. These generalizations must be guided by some inductive bias – some abstract knowledge – that leads them to prefer the correct hypotheses even in the absence of directly supporting evidence. What form do these inductive constraints take? It is often argued or assumed that they reflect innately specified knowledge of language. A classic example of such an argument moves from the phenomenon of auxiliary fronting in English interrogatives to the conclusion that children must innately know that syntactic rules are defined over hierarchical phrase structures rather than linear sequences of words (e.g., [Chomsky, 1965], [Chomsky, 1971],[Chomsky, 1980] and [Crain and Nakayama, 1987]). Here we use a Bayesian framework for grammar induction to address a version of this argument and show that, given typical child-directed speech and certain innate domain-general capacities, an ideal learner could recognize the hierarchical phrase structure of language without having this knowledge innately specified as part of the language faculty. We discuss the implications of this analysis for accounts of human language acquisition.