The intelligibility of interrupted and temporally altered speech: Effects of context, age, and hearing loss

Abstract

Temporal constraints on the perception of interrupted speech were investigated by comparing the intelligibility of speech that was periodically gated (PG) and subsequently either temporally compressed (PG TC ) by concatenating remaining speech fragments or temporally expanded (PG TE ) by doubling the silent intervals between speech fragments. Experiment 1 examined the effects of PG TC and PG TE at different gating rates (0.5 -16 Hz) on the intelligibility of words and sentences for young normal-hearing adults. In experiment 2, older normal-hearing (ONH) and older hearingimpaired (OHI) adults were tested with sentences only. The results of experiment 1 indicated that sentences were more intelligible than words. In both experiments, PG TC sentences were less intelligible than either PG or PG TE sentences. Compared with PG sentences, the intelligibility of PG TE sentences was significantly reduced by the same amount for ONH and OHI groups. Temporal alterations tended to produce a U-shaped rate-intelligibility function with a dip at 2-4 Hz, indicating that temporal alterations interacted with the duration of speech fragments. The present findings demonstrate that both aging and hearing loss negatively affect the overall intelligibility of interrupted and temporally altered speech. However, a mild-to-moderate hearing loss did not exacerbate the negative effects of temporal alterations associated with aging.

Aging and Spectro-Temporal Integration of Speech

“…This lack of an age effect for interrupted speech contrasts with some reports in the literature (e.g., Gordon-Salant & Fitzgibbons, 1993 ; Shafiro et al., 2015 ) but two important stimulus characteristics must be considered when making such comparisons: (a) the rate of interruption and (b) the speech material used. In terms of the rate of interruption, rates in the region of 10 Hz can have little effect on the intelligibility of otherwise intact sentence material in both younger and older normal-hearing listeners, whereas lower interruption rates can result in marked deficits ( Saija et al., 2014 ; Shafiro, Sheft, & Risley, 2016 ). Even for rates in the 10-Hz region, however, performance depends on the speech material.…”

“…Even for rates in the 10-Hz region, however, performance depends on the speech material. The high intelligibility reported by Shafiro et al. (2016) for 8 - and 16-Hz interruptions was for the Hearing in Noise Test [HINT] sentences while that reported by Saija et al.…”

“…Even for rates in the 10-Hz region, however, performance depends on the speech material. The high intelligibility reported by Shafiro et al (2016) for 8 -and 16-Hz interruptions was for the Hearing in Noise Test [HINT] sentences while that reported by Saija et al (2014) for 10-Hz interruptions was for everyday Dutch sentences. In contrast, Gordon-Salant and Fitzgibbons (1993) used the low-predictability Revised Speech Perception in Noise [LP R-SPIN] sentences and found a significant reduction in performance for both younger and older normal-hearing listeners when the sentences were interrupted at a rate of 12.5 Hz.…”

Temporal Resolution Needed for Auditory Communication: Measurement With Mosaic Speech

“…One example is the word intelligibility (articulation) of speech in which 50-ms portions are alternately played and silenced, as reported by Miller and Licklider ( 1950 ), who discovered the illusory continuity (see also Vicario, 1960 ). Intelligibility does not change in such “gated speech” even if the temporal gaps are simply removed, shortening the total duration (Fairbanks and Kodman, 1957 ; Shafiro et al, 2016 ). The perception of locally time-reversed speech is also to be noted.…”

Glimpsing speech interrupted by speech-modulated noise

“…Speech-in-noise perception, particularly in multi-talker environments, is likely dependent on how the AM of competing sources interfere with the recognition of glimpsed speech. Furthermore, while periodic interruption methods are currently used to study a wide variety of effects on speech recognition (e.g., Nagaraj and Knapp, 2015;Wilson and Irish, 2015;Bhargava et al, 2016;Molis and Gallun, 2016;Shafiro et al, 2016;Smiljanic et al, 2016;Smith and Fogerty, 2017); this methodology needs to be verified with more naturalistic conditions where non-periodic speech interruptions are defined according to the temporal intervals of speech glimpses in realistic masking conditions, such as during speech-on-speech masking. This is a more ecologically valid case and necessary to help bridge results from the interrupted speech literature to more naturalistic speech glimpsing models.…”