Sensorimotor Representations of Meaning in Early Language Acquisition

Abstract

<p>Evidence suggests that children's pre-linguistic conceptual knowledge significantly influences the course of language acquisition. In a series of nine experiments we investigate this influence. We begin with two experiments using adult human subjects, in which we develop an analogue of children's early sensorimotor semantic representations and demonstrate that we have captured important aspects of meaning. We then use these sensorimotor semantic representations in simulation experiments using neural network models of language acquisition. First, we provide evidence that having these sensorimotor representations improves grammatical learning. Then we demonstrate that with these rich semantic representations there are strong correlations between the time course of lexical and grammatical learning analogous to those found in children. We suggest that this supports the position that grammar emerges from the formation of a rich lexicon. Finally, we show that it is not necessary to provide these sensorimotor representations for all words. We provide evidence that, given a directly grounded foundation of children's earliest words, the model can indirectly acquire grounded, embodied semantic representations for novel ungrounded words. Our results thus provide evidence that the initial structure of children's conceptual or semantic 'space' provides an important constraining and simplifying foundation that influences the course of later language acquisition.</p>