Spoken word processing in Rett syndrome: Evidence from event-related potentials

This study examined the feasibility of using auditory event-related potentials to evaluate spoken word processing during passive listening in girls with Rett syndrome (n = 11) and typical peers (n = 33), age 4-12 years. The typical group demonstrated the expected pattern of more negative amplitudes within 200-500 ms in response to words than nonwords at left temporal sites. In participants with Rett syndrome, word-nonword differentiation was observed at the right temporal sites. More negative left hemisphere amplitudes in response to words were associated (at trend level) with better receptive language skills and more adaptive behavior. The results indicate that girls with Rett syndrome differentiate known words from novel nonwords, but may do so using potentially atypical neural processes. Brain-behavior correlations support validity of the proposed neural markers of word processing, making passive listening paradigms a promising approach for assessing speech and language processing in participants with limited spoken language skills.