The use of F0 in speech segmentation by adults with dyslexia and skilled readers

This paper examines the use of intonational cues for word segmentation in skilled French readers and adult dyslexics, and more specifically, the influence of the fundamental frequency (F0). Participants listened to phonemically identical sequences such as /selami/, c'est la mie/l'amie 'it's the crumb/friend', and had to perform a two-alternative forced choice task in Exp1 and a word repetition task in Exp2. The F0 slope and/or mean value of the first vowel /a/ of the natural consonant-initial production la mie were manipulated to test whether it influences perceived segmentation. The present study shows that not only increasing the F0 mean value but also rotating the F0 slope alone led to more vowel initial segmentation, thus biasing speech segmentation in both tasks. A similar segmentation strategy was found for both groups of participants. Our findings suggest that both skilled readers and adult dyslexics compute F0 trajectories to find the beginning of content words.