The effects of dialect variation on speech intelligibility in a multitalker background

Abstract

ABSTRACTSpeech intelligibility in a multitalker background can be affected by the language of both the talker and the interfering speech. This study investigated whether this interaction is modulated by dialect variations of the same language. American English listeners were presented with target sentences in either their own General American English (GAE) or a different accent (Southern American English [SAE]) masked by either GAE or SAE two-talker babble at three sound to noise ratios (SNRs): +3, 0, and –3 dB. All speech materials were produced by male talkers. Across all conditions, SAE target was more intelligible than GAE. Intelligibility of either target decreased as the level of the interfering babble noise increased. Target accent interacted with masking accent: at +3 dB SNR, GAE (and not SAE) was the more effective masker. The target-masker interaction was different as listening conditions deteriorated: at 0 and –3 dB SNR, masking accent did not affect GAE target, but when the target was SAE, the SAE masker (and not GAE) was more effective. Thus, at increased noise levels, listeners benefited from the mismatch between the target and masking accents only when the target was in a nonnative accent. These results demonstrate that dialect variation can influence listeners’ performance in a multitalker environment. The apparent asymmetry in intelligibility of accents may be in part related to dialect-specific prosodic and phonetic features.