Sequence learning attenuates cortical responses in both frontal and perceptual cortices in early infancy
Prior work using a variety of imaging modalities has found that the frontal lobe is involved in higher-order sequential and statistical learning in young infants. Separate lines of work have found evidence of modulation of posterior sensory cortices during and after learning tasks. How do these processes relate together? Here, we build from a well-regarded EEG task that found evidence that the frontal lobe of young infants tracked higher-order sequential information (Basirat et al., 2014) and ask whether posterior perceptual cortices respond differentially to predictable vs. unpredictable sequences as well. First, replicating and extending past work, we found evidence of frontal lobe involvement in this task. Second, consistent with our hypotheses, we found that there is a corresponding attenuation of neural responses in the posterior perceptual cortices (temporal and occipital) to predictable compared to unpredictable audiovisual sequences. This study provides convergent evidence that the frontal lobe is crucial for higher-level learning in young infants but that it likely works as part of a large, distributed network of regions to modulate infant neural responses as a result of learning. Overall, this work challenges the view that the infant brain is not dynamic and disconnected, lacking in long-range neural connections. Instead, this paper reveals patterns of a highly dynamic and interconnected infant brain that change rapidly as a result of new, learnable experiences.