Tracking the pace of reading with finger movements

Recent experimental evidence in visual perception analysis shows that eye and finger movements strongly correlate during scene exploration, at both individual and group levels. A familiar context which exploits this synergistic behaviour is when children learn to read, with the practice of finger-pointing to text as a support for their attention focus, directional movement and voice-print match. Using a tablet to display short texts, we collected evidence on the finger-pointing behaviour of 3rd-6th Italian graders engaged in both silent and oral reading. "Finger-tracking" data, sampled by the tablet and aligned with the text, made it possible to time a child's reading paceat word and sentence level. Results are shown to replicate established benchmarks in the reading literature, such as the difference in reading pace between age-matched typical and atypical readers as a function of word frequency and length, and neighbourhood entropy and Old20. Atypical readers show increasing difficulty with longer words, with a steeper time increment for word length > 6, integrating previous evidence. In addition, neighbourhood density plays a sparse facilitative role in atypical reading, with no significant interaction with neighbourhood entropy, pointing to a non trivial developmental interplay between sublexical reading and the richness of the Italian orthographic-phonological lexicon. Despite their different dynamics, optical and tactile strategies for text exploration prove to be highly congruent: this suggests that finger-tracking can be used as an ecological proxy for eye-tracking in reading assessment.