Martinez-Alvarez, A. 1, 2 , Gervain, J. 3, 4 , Pons, F. 1, 5 & de Diego-Balaguer, R. 1, 2, 6
1 University of Barcelona
2 Cognition and Brain Plasticity Unit, IDIBELL
3 CNRS
4 Université Paris Descartes
5 Institute of Neurosciences, UB
6 ICREA
A core ability in infant language development involves rule extraction. Previous studies investigated the brain basis of repetition-based rules (e.g. ABB: 'mubaba', 'penana', ABA: 'bamuba', 'napena') in infancy and found increased responses to repetition sequences in temporal and left frontal regions (Gervain et al. 2008). However, the neural basis of infant non-repetition based rule learning remains unexplored. Behaviorally, such rules are first learned at 15 months. Such long-distance dependencies are commonly found in syntax and morphology (e.g. is walking, unbelievable). To examine this type of rules we presented 9-10-month-old infants with sequences containing an AXC-type structure, where A and C predict one another (e.g., 'pedibu', 'pegabu') or a random control structure where there is no such dependency (e.g., 'dibupe', 'bugape'). We increased the pitch of the first and third syllables. Infants' brain activity was measured using near-infrared spectroscopy (NIRS). Preliminary data show a tendency for the rule condition to produce a larger activation in temporal and frontal areas, more prominent over right-lateralized regions. The present results suggest that pitch might highlight dependencies that cannot otherwise be learned yet at a given age. This study may contribute to our understanding of the brain basis of rule learning processes underlying language acquisition.