First language acquisition is facilitated by several characteristics of infant-directed speech, but we know little about their relative contribution to learning different aspects of language. We investigated infant-directed speech effects on the acquisition of a linear artificial grammar in two experiments. We examined the effect of incremental presentation of strings (starting small) and prosody (comparing monotonous, arbitrary and phrase prosody). Presenting shorter strings before longer ones led to higher learning rates compared to random presentation. Prosody marking phrases had a similar effect, yet, prosody without marking syntactic units did not facilitate learning. These studies were the first to test the starting small effect with a linear artificial grammar, and also the first to investigate the combined effect of starting small and prosody. Our results suggest that starting small and prosody facilitate the extraction of regularities from artificial linguistic stimuli, indicating they may play an important role in natural language acquisition.
Complexity, Training Paradigm Design, and the Contribution of Memory Subsystems to Grammar Learning
