The learnability of Auditory Center-embedded Recursion

A growing body of research investigates how humans learn complex hierarchical structures with center-embedded recursion (Bahlmann, Schubotz, & Friderici, 2008; Poletiek & Lai, 2012). Increasing evidence indicates that properties of the learning input have an impact on learning this type of recursion. For instance, recent studies found that staged input, fewer unique exemplars and unequal repetition facilitate learning (e.g. Lai, Krahmer, & Sprenger, 2014; Lai & Poletiek, 2011, 2013). Most of these studies investigated learning center-embedded recursion through visual input, whereas few studies examined the processing of auditory input. In the current study, we test: 1) whether participants are able to learn center-embedded recursive structure from exclusively auditory input; 2) whether the facilitative cues (ordering and frequency distribution) are attuned to the auditory modality. Our results successfully demonstrate the learning of auditory sequences with center-embedded recursion, and replicated the effect with visual input in the previous study (Lai et al., 2014).