Perception of interrupted speech: effects of dual-rate gating on the intelligibility of words and sentences

J Acoust Soc Am. 2011 Oct;130(4):2076-87. doi: 10.1121/1.3631629.

Abstract

Perception of interrupted speech and the influence of speech materials and memory load were investigated using one or two concurrent square-wave gating functions. Sentences (Experiment 1) and random one-, three-, and five-word sequences (Experiment 2) were interrupted using either a primary gating rate alone (0.5-24 Hz) or a combined primary and faster secondary rate. The secondary rate interrupted only speech left intact after primary gating, reducing the original speech to 25%. In both experiments, intelligibility increased with primary rate, but varied with memory load and speech material (highest for sentences, lowest for five-word sequences). With dual-rate gating of sentences, intelligibility with fast secondary rates was superior to that with single rates and a 25% duty cycle, approaching that of single rates with a 50% duty cycle for some low and high rates. For dual-rate gating of words, the positive effect of fast secondary gating was smaller than for sentences, and the advantage of sentences over word-sequences was not obtained in many dual-rate conditions. These findings suggest that integration of interrupted speech fragments after gating depends on the duration of the gated speech interval and that sufficiently robust acoustic-phonetic word cues are needed to access higher-level contextual sentence information.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Acoustic Stimulation
  • Adult
  • Analysis of Variance
  • Audiometry, Speech
  • Auditory Threshold
  • Cues
  • Female
  • Humans
  • Male
  • Memory
  • Phonetics*
  • Sound Spectrography
  • Speech Acoustics*
  • Speech Intelligibility*
  • Speech Perception*
  • Time Factors
  • Young Adult