Spontaneous supra-modal encoding of number in the infant brain
Giulia Gennari1, Stanislas Dehaene2, Chanel Valera3
1Cognitive Neuroimaging Unit U992, Institut National de la Santé et de la Recherche Médicale, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Direction de la Recherche Fondamentale/Institut Joliot, Centre National de la Recherche Scientifique ERL9003, NeuroSpin Center, Université Paris-Saclay, 91191 Gif-sur-Yvette, France; Neuroscience Institute, New York University Grossman School of Medicine, New York, NY 10016, USA.
Abstract:
The core knowledge hypothesis postulates that infants automatically analyze their environment along abstract dimensions, including numbers. According to this view, approximate numbers should be encoded quickly, pre-attentively, and in a supra-modal manner by the infant brain. Here, we directly tested this idea by submitting the neural responses of sleeping 3-month-old infants, measured with high-density electroencephalography (EEG), to decoders designed to disentangle numerical and non-numerical information. The results show the emergence, in approximately 400 ms, of a decodable number representation, independent of physical parameters, that separates auditory sequences of 4 vs. 12 tones and generalizes to visual arrays of 4 vs. 12 objects. Thus, the infant brain contains a number code that transcends sensory modality, sequential or simultaneous presentation, and arousal state.
