Comprehension of Ultra-fast Speech – Blind vs. "normally Hearing" Persons

This study explores how much speech can be temporally compressed and still understood by blind people who have daily practice with speech synthesis vs. sighted persons without such training. Three text modes were generated (formant synthesis, natural speech with and without pauses). These texts were presented to sighted listeners at rates between 9-14 s/s and to blind listeners between 17-22 s/s. The removal of pauses in compressed natural speech shows significant benefits at only few speaking rates. Results also show that synthesis is understood worst by sighted but best by blind listeners. The fact that some of the blind still understood speech at 22 s/s reveals the enormous flexibility of the brain in speech perception during the processing of ultra-fast speech.