We propose that the pattern of performance in the phonotactics task reflects specialization in language processing that is akin to developmental processes that occur in perceptual narrowing for faces and phonemes. For example, in speech perception, across the first year of life, infants transition from discriminating native and non-native phoneme contrasts to discriminating primarily those that are present in their own native languages. The idea is that with experience, cognitive and perceptual systems are shaped by the input to promote the rapid processing that is necessary to interpret information in faces and voices. Some openness or flexibility in information processing is lost, but the benefit is the formation of a system that is adapted to process just the types of information that are prevalent in the environment.