Does learning to read change the perception of speech? Evidence from perceptual recalibration of speech sounds in adult illiterates, semi-literates, and literates of Tamil

How do different levels of representation interact in the mind? Key evidence for answering this question comes from experimental work that investigates the influence of knowledge of written language on spoken language processing. Here we tested whether learning orthographic representations (through reading) influences pre-lexical phonological representations in spoken-word recognition using a perceptual learning paradigm. Perceptual learning is well suited to reveal differences in pre-lexical representations that might be caused by learning to read because it requires the functional use of pre-lexical representations in order to generalize a learning experience. In a large-scale behavioural study in Chennai, India, 97 native speakers of Tamil with varying reading experience (from completely illiterate to highly literate) participated. In marked contrast to their performance in other cognitive tasks, even completely illiterate participants showed a perceptual learning effect that was not moderated by reading experience. This finding suggests that pre-lexical phonological representations are not substantially changed by learning to read and thus poses important constraints for the debate about the degree of interactivity between different levels of representations during human information processing.