We predicted that infants with smaller vocabularies would show greater flexibility in learning novel phonotactic patterns that conflict with native language sound patterns and that infants with larger vocabularies would show greater language-specific specialization. To test this prediction, we performed a hierarchical regression analysis predicting infants’ listening time difference scores to violation test items minus consistent test items. The correlations between looking time difference scores and vocabulary size and cognitive scores are illustrated in Figs. 1 and 2.