Goldilocks Forgetting in Cross-Situational Learning

Given that there is referential uncertainty (noise) when learning words, to what extent can forgetting filter some of that noise out, and be an aid to learning? Using a Cross Situational Learning model we find a U-shaped function of errors indicative of a "Goldilocks" zone of forgetting: an optimum store-loss ratio that is neither too aggressive nor too weak, but just the right amount to produce better learning outcomes. Forgetting acts as a high-pass filter that actively deletes (part of) the referential ambiguity noise, retains intended referents, and effectively amplifies the signal. The model achieves this performance without incorporating any specific cognitive biases of the type proposed in the constraints and principles account, and without any prescribed developmental changes in the underlying learning mechanism. Instead we interpret the model performance as more of a by-product of exposure to input, where the associative strengths in the lexicon grow as a function of linguistic experience in combination with memory limitations. The result adds a mechanistic explanation for the experimental evidence on spaced learning and, more generally, advocates integrating domain-general aspects of cognition, such as memory, into the language acquisition process

What can developmental disorders tell us about the neurocomputational constraints that shape development? the case of Williams syndrome

The uneven cognitive phenotype in the adult outcome of Williams syndrome has led some researchers to make strong claims about the modularity of the brain and the purported genetically determined, innate specification of cognitive modules. Such arguments have particularly been marshaled with respect to language. We challenge this direct generalization from adult phenotypic outcomes to genetic specification and consider instead how genetic disorders provide clues to the constraints on plasticity that shape the outcome of development. We specifically examine behavioral studies, brain imaging, and computational modeling of language in Williams syndrome but contend that our theoretical arguments apply equally to other cognitive domains and other developmental disorders. While acknowledging that selective deficits in normal adult patients might justify claims about cognitive modularity, we question whether similar, seemingly selective deficits found in genetic disorders can be used to argue that such cognitive modules are prespecified in infant brains. Cognitive modules are, in our view, the outcome of development, not its starting point. We note that most work on genetic disorders ignores one vital factor, the actual process of ontogenetic development, and argue that it is vital to view genetic disorders as proceeding under different neurocomputational constraints, not as demonstrations of static modularity

The Composite Nature of Interlanguage as a Developing System

This paper explores the nature of interlanguage (IL) as a developing system with a focus on the abstract lexical structure underlying IL construction. The developing system of IL is assumed to be ‘composite’ in that in second language acquisition (SLA) several linguistic systems are in contact, each of which may contribute different amounts to the developing system. The lexical structure is assumed to be ‘abstract’ in that the mental lexicon contains abstract elements called ‘lemmas’, which contain information about individual lexemes, and lemmas in the bilingual mental lexicon are language-specific and are in contact in IL production. Based on the research findings, it concludes that language transfer in IL production should be understood as lemma transfer of the learner's first language (L1) lexical structure at three abstract levels: lexical-conceptual structure, predicate-argument structure, and morphological realization patterns, and IL construction is driven by an incompletely acquired abstract lexical structure of a target language (TL) item

Beyond naming patterns in children with WFDs: definitions for nouns and verbs

Children who experience difficulties in naming are described as having word finding difficulties (WFDs). In the present study 31 children with WFDs were identified through a wider survey of educational provision for those with language and communication difficulties. The children were included if they were between 6;4-7;10 years, had normal non-verbal intelligence, no major articulation difficulties and had WFDs as diagnosed by standard scores below 75 on Test of Word Finding Difficulties (TWF, German, 1989). Three control groups were identified who were matched on: chronological age (N = 31), naming age (N = 31) and level of receptive grammar (N = 31). Children?s accuracy of naming and latency to name were assessed for pictures of objects and actions. Children were asked to define the object and action terms at a later point. Children with WFDs were significantly less accurate in naming than their age matched peers but equivalent to that of the language matched peers. The group of children with WFDs were the slowest to accurately name all sets of items. All groups of children were less accurate in the provision of definitions for action terms than object terms. Overall the children with WFDs provided fewer accurate definitions than their chronological age matched peers. The nature of the children?s definitions indicated that they also differed from their language-matched peers. Particular difficulties were noted in the provision of semantic categorisation information. A range of standardised language assessments did not account for these difficulties. The findings are discussed in relation to the idea that WFDs are caused by impoverished semantic representations

Directional adposition use in English, Swedish and Finnish

Directional adpositions such as to the left of describe where a Figure is in relation to a Ground. English and Swedish directional adpositions refer to the location of a Figure in relation to a Ground, whether both are static or in motion. In contrast, the Finnish directional adpositions edellä (in front of) and jäljessä (behind) solely describe the location of a moving Figure in relation to a moving Ground (Nikanne, 2003). When using directional adpositions, a frame of reference must be assumed for interpreting the meaning of directional adpositions. For example, the meaning of to the left of in English can be based on a relative (speaker or listener based) reference frame or an intrinsic (object based) reference frame (Levinson, 1996). When a Figure and a Ground are both in motion, it is possible for a Figure to be described as being behind or in front of the Ground, even if neither have intrinsic features. As shown by Walker (in preparation), there are good reasons to assume that in the latter case a motion based reference frame is involved. This means that if Finnish speakers would use edellä (in front of) and jäljessä (behind) more frequently in situations where both the Figure and Ground are in motion, a difference in reference frame use between Finnish on one hand and English and Swedish on the other could be expected. We asked native English, Swedish and Finnish speakers’ to select adpositions from a language specific list to describe the location of a Figure relative to a Ground when both were shown to be moving on a computer screen. We were interested in any differences between Finnish, English and Swedish speakers. All languages showed a predominant use of directional spatial adpositions referring to the lexical concepts TO THE LEFT OF, TO THE RIGHT OF, ABOVE and BELOW. There were no differences between the languages in directional adpositions use or reference frame use, including reference frame use based on motion. We conclude that despite differences in the grammars of the languages involved, and potential differences in reference frame system use, the three languages investigated encode Figure location in relation to Ground location in a similar way when both are in motion. Levinson, S. C. (1996). Frames of reference and Molyneux’s question: Crosslingiuistic evidence. In P. Bloom, M.A. Peterson, L. Nadel & M.F. Garrett (Eds.) Language and Space (pp.109-170). Massachusetts: MIT Press. Nikanne, U. (2003). How Finnish postpositions see the axis system. In E. van der Zee & J. Slack (Eds.), Representing direction in language and space. Oxford, UK: Oxford University Press. Walker, C. (in preparation). Motion encoding in language, the use of spatial locatives in a motion context. Unpublished doctoral dissertation, University of Lincoln, Lincoln. United Kingdo

Usage-based and emergentist approaches to language acquisition

It was long considered to be impossible to learn grammar based on linguistic experience alone. In the past decade, however, advances in usage-based linguistic theory, computational linguistics, and developmental psychology changed the view on this matter. So-called usage-based and emergentist approaches to language acquisition state that language can be learned from language use itself, by means of social skills like joint attention, and by means of powerful generalization mechanisms. This paper first summarizes the assumptions regarding the nature of linguistic representations and processing. Usage-based theories are nonmodular and nonreductionist, i.e., they emphasize the form-function relationships, and deal with all of language, not just selected levels of representations. Furthermore, storage and processing is considered to be analytic as well as holistic, such that there is a continuum between children's unanalyzed chunks and abstract units found in adult language. In the second part, the empirical evidence is reviewed. Children's linguistic competence is shown to be limited initially, and it is demonstrated how children can generalize knowledge based on direct and indirect positive evidence. It is argued that with these general learning mechanisms, the usage-based paradigm can be extended to multilingual language situations and to language acquisition under special circumstances

Interficies entre los componentes del lenguaje: “Bootstrapping” (cambio funcional) en “períodos sensibles” después de alcanzar una “masa crítica” en el uso

Conceiving the architecture of language components as modules requires not only specifying how they interact in terms of units and rules, but also how they change in the learning process. This paper specifically proposes that the progressive interactive bootstrap between language components (in a sensitive period and after a critical mass is attained) is the key factor of the expert learning and use of language. Partial evidence for this consideration are the non-linear learning curves in sequences over time that the different components exhibit. To this end, we present some evidence of changes in the lexicon, grammatical categories and inflection. Finally, we postulate that explicitly well documented learning relationships among components (in time and content) should be a central goal in the future language acquisition research.Considerar como módulos a los componentes del lenguaje requiere especificar,no solo como interactúan entre ellos, según sus reglas y unidades,sino también como van cambiando en los procesos de aprendizaje. Este artículopropone que el factor clave para un aprendizaje y un uso experto del lenguajees el bootstrapping entre dichos componentes (en un periodo sensible y despuésde alcanzar un nivel determinado de masa crítica). Los datos (todavía parciales)para fundamentar esta propuesta son las curvas no lineales de aprendizajeque se observan en las secuencias temporales de dichos componentes, y susposibles relaciones. Finalmente, se postula que un objetivo central en el futuro de la investigación en la adquisición del lenguaje debe consistir en documentar(según tiempo y contenido) el aprendizaje teniendo en cuenta las relacionesentre los componentes