SOBRE O PAPEL DA LÍNGUA NO DESENVOLVIMENTO DE HABILIDADES COGNITIVAS SUPERIORES: REPRESENTAÇÃO, RECURSIVIDADE E COGNIÇÃO NUMÉRICA / ON THE ROLE OF LANGUAGE IN THE DEVELOPMENT OF HIGHER COGNITIVE FUNCTIONS: REPRESENTATION, RECURSION AND NUMERICAL COGNITION
DATA DE PUBLICAÇÃO
This thesis investigates the possible relationship between two central aspects of the human cognition, namely, the capacity of any child to acquire a natural language (in the absence of neurological or social impairments) and the development of high cognitive abilities, which appear to be specifically human. As far as the latter is concerned, numeral abilities involving calculus with exact quantities and the ability to integrate information from different cognitive domains are focused on here. Two fundamental aspects of human languages are considered in this regard: representation, in so far as languages include a lexicon, and recursion, in so far as they incorporate a computational system that operates on lexical items recursively. This study is inserted into a research program aiming at articulating a minimalist conception of language with a theory of language processing and acquisition (Corrêa, 2005-2009; Correa &Augusto, 2007). The idea that language is crucial for the integration of information from different cognitive systems (Spelke, 1992-2010) is also incorporated here. The working hypothesis guiding this investigation is that the role of language in the development of numerical abilities can be related to those two fundamental aspects: language provides the means of representing exact quantities, in so far as the lexicon includes numerals (number words) and is endowed with recursive operations that enable information stemming from different domains to be integrated in a single linguistic expression. Moreover, recursion is a property that can be shared by systems pertaining to different cognitive domains. Two sets of experiments are reported, each of them devoted to questions pertaining to representation and recursion, respectively. Five experiments were conducted with 2-6 year olds and adults. An experiment carried out only with adults explored the possibility of a cross-domain priming effect to be obtained when recursive structures (sentences with relative clauses and recursive numeral expressions) are sequentially presented. Additionally, four aphasic patients were submitted to one task of each set of experiments. The results suggest early sensitivity to the distinction between numerals and other sorts of number words (quantifiers). Numerals appear to be associated with exact quantities even before their exact meaning (from 1- 5) has been acquired. Recursion appears to be operating before the age of six. Difficulties in dealing with the processing of recursive linguistic structures usually ascribed to children appear to be due to non-linguistic factors and/or to methodological problems in the assessment of children¿s recursive abilities. Cross domain structural priming effects failed to be obtained. As a whole, the results are compatible with the hypothesis orienting this thesis, though caution is required when cross domain effects are considered.