The Effect of Dialect and Accent on Digit Perception in Noise in Young Listeners With Normal Hearing

Dialect and accent factors can impact speech-in-noise testing outcomes. This study investigated these effects on the Integrated Digit-in-Noise (iDIN) test among young adults with normal hearing.

Dialects involve variations in grammar, vocabulary, and syntax, while accents influence only pronunciation, reflecting geographical or social origins. In Study 1, which examined dialect effects, 33 participants-all native speakers of Mandarin and various Wu dialects except Ningboese-underwent iDIN testing in both Ningboese and Mandarin (as a reference condition). In Study 2, which focused on accent effects, 39 participants-all native speakers of Mandarin and Ningboese, including 19 standard Ningboese and 20 accented Ningboese speakers -underwent iDIN testing in both Mandarin and standard Ningboese at fixed signal-to-noise ratio and adaptive measurements.

In Study 1, the results revealed statistically significant differences between the Mandarin and Ningboese iDIN results across all conditions except for the 2-digit sequences. In Study 2, the results showed no significant differences in 3-digit SRTs between standard and accented Ningboese speakers, but a significant difference in 5-digit SRTs.

In Mainland China or other regions with high linguistic diversity, accounting for dialect and accent exposure is crucial in evaluating speech recognition, and a 2-digit DIN may be more suitable for valid hearing screening.