Usage-based approaches to language learning hold that we learn constructions (form-function mappings, conventionalized in a speech community) from language usage by means of general cognitive mechanisms (exemplar-based, rational, associative learning). The language system emerges from the conspiracy of these associations. Although frequency of usage drives learning, not all constructions are equally learnable by all learners. Even after years of exposure, adult second language learners focus more in their language processing upon open-class words than on grammatical cues. I present a usage-based analysis of this phenomenon in terms of fundamental principles of associative learning: Low salience, low contingency, and redundancy all lead to form-function mappings being less well learned. Compounding this, adult acquirers show effects of learned attention and blocking as a result of L1-tuned automatized processing of language. I review a series of experimental studies of learned attention and blocking in second language acquisition (L2A). I describe educational interventions targeted upon these phenomena. Form-focused instruction recruits learners’ explicit, conscious processing capacities and allows them to notice novel L2 constructions. Once a construction has been represented as a form-function mapping, its use in subsequent implicit processing can update the statistical tallying of its frequency of usage and probabilities of form-function mapping, consolidating it into the system.

本シンポジウムでは言語の基盤について発達的・進化的観点からアプローチすることを試みる。従来、言語の基盤の問題は個体発生に関心を持つ研究者と、系統発生に関心を持つ研究者がそれぞれの立場から議論を行なってきた。特に、言語を思考のツールとして捉える研究者と、コミュニケーションのツールとして捉える研究者の議論は、今日まで言語の様々な領域固有領域一般の特性を明らかにしてきている。本シンポジウムでは発達言語学、進化言語学を専門とする登壇者が、認知、推論、社会性、コミュニケーションなどさまざまな観点から言語の基盤を巡るホットトピックについて論じ、これからの言語研究が切り拓くべき問題について議論する。