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Adaptability is a distinguishing feature of the human species: We thrive as hunter-gatherers, farmers, and urbanites. What properties of our brains make us highly adaptable? Here we review neuroscience studies of sensory loss, language acquisition, and cultural skills (reading, mathematics, programming). The evidence supports a flexible specialization account. On the one hand, adaptation is enabled by evolutionarily prepared flexible learning systems, both domain-specific social learning systems (e.g., language) and domain-general systems (frontoparietal reasoning). On the other hand, the functional flexibility of our neural wetware enables us to acquire cognitive capacities not selected for by evolution. Heightened plasticity during a protracted period of development enhances cognitive flexibility. Early in life, local cortical circuits are capable of acquiring a wide range of cognitive capacities. Exuberant cross-network connectivity makes it possible to combine old neural parts in new ways, enabling cognitive flexibility such as language acquisition across modalities (spoken, signed, braille) and cultural skills (math, programming). Together, these features of the human brain make it uniquely adaptable. 

The picture naming task is common both as a clinical task and as a method to study the neural bases of speech production in the healthy brain. However, this task is not reflective of most naturally occurring productions, which tend to happen within a context, typically in dialogue in response to someone else’s production. How the brain basis of the classic “confrontation picture naming” task compares to the planning of utterances in dialogue is not known. Here we used magnetoencephalography (MEG) to measure neural activity associated with language production using the classic picture naming task as well as a minimal variant of the task, intended as more interactive or dialogue-like. We assessed how neural activity is affected by the interactive context in children, teenagers, and adults. The general pattern was that in adults, the interactive task elicited a robust sustained increase of activity in frontal and temporal cortices bilaterally, as compared to simple picture naming. This increase was present only in the left hemisphere in teenagers and was absent in children, who, in fact, showed the reverse effect. Thus our findings suggest a robustly bilateral neural basis for the coordination of interaction and a very slow developmental timeline for this network.