Consistency and variation in recognition of text and speech interrupted at variable rates

Abstract

Recent research indicates that recognition of interrupted text can predict speech intelligibility under adverse listening conditions. However, factors underlying the relationship between perceptual processing of speech and text are not fully understood. We examined contributions of underlying linguistic and perceptual structure by comparing recognition of printed and spoken sentences interrupted at different rates (0.5—64 Hz) in 14 normal-hearing adults. The interruption method approximated deletion and retention of rate-specific linguistic information across the two modalities by substituting white space for silent intervals. Results indicate a remarkably similar U-shaped pattern of cross-rate variation for both modalities, with minima at 2 Hz. Nevertheless, at high and low interruption rates text recognition exceeded speech recognition, while the reverse trend was observed at middle rates. Surprisingly, no significant correlations were obtained in recognition accuracy between text and speech conditions. These findings indicate a high degree of perceptual constancy in recognition of interrupted text and speech, which may rely on retention of rate-specific linguistic and perceptual information retained after the interruptions. On the other hand, results also indicate rate-specific variation in perceptual processing of text and speech, which may potentially affect the degree to which recognition accuracy in one modality is predictive of the other.