Cues for perception of synthetic and natural diphthongs in either noise or reverberation

Abstract

The relationship between relative intensity of transition segments and identification of diphthongs has been investigated. In the first experiment, synthesized stimuli were used. The stimuli differed in the amount of attenuation of the transition segment which ranged from 0 to 15 dB. It was expected that [diphthong in text] responses would be obtained for stimuli with attenuated transitions. The stimuli were tested in quiet, noise, and reverberation with ten normal-hearing and seven hearing-impaired subjects. For the stimulus with the most attenuated transition, the normal-hearing subjects gave no [diphthong in text] responses and the hearing-impaired subjects gave only 20% [diphthong in text] responses in quiet. However, in noise, both groups of subjects gave 70% [diphthong in text] responses and in reverberation, the normal-hearing subjects gave 95% and the hearing-impaired subjects gave 90% [diphthong in text] responses. Generally, less transition attenuation was needed for the hearing-impaired than for the normal-hearing subjects to give [diphthong in text] responses. These findings indicated that identification errors in noise and reverberation for naturally produced diphthongs might be related to the intensity of their transition segments. In the second experiment, naturally produced diphthongs [diphthongs in text] from the Nábĕlek et al. [J. Acoust. Soc. Am. 92, 1228-1246 (1992)] study were spectrally analyzed. There were 30 different tokens for each diphthong. The results of the analyses indicated significant correlations between the number of identification errors for these diphthongs made by either normal-hearing or hearing-impaired subjects and the relative intensities of the F2 transition segment. In both noise and reverberation there were fewer errors for the diphthong tokens characterized by high intensity F2 transitions.

Congruent and Incongruent Semantic Context Influence Vowel Recognition

“…Similarly, in reverberant conditions without supporting context, errors in the identification of both vowels (e.g., Nábêlek, Czyzewski, & Crowley, 1993;Nábêlek & Letowski, 1988;Nábêlek et al, 1996) and consonants (e.g., Cox, Alexander, & Gilmore, 1987;Nábêlek, Letowski, & Tucker, 1989) have been reported. However, studies have also shown that naturally spoken vowels can be highly identifiable in reverberation or noise alone (e.g., Nábêlek, 1988;Nábêlek & Dagenais, 1986;Nábêlek et al, 1996). The speech of some talkers appears to be more susceptible to reverberation degradation than that of others (Cox et al, 1987) and different speakers may produce confusion with different vowels (Nábêlek & Letowski, 1988).…”

“…Poorer vowel recognition performance in noise or reverberation has often been reported across many vowels (e.g., Nábêlek, 1988;Nábêlek & Dagenais, 1986;Nábêlek et al, 1996). However, when Nábêlek and Letowski (1988) looked at vowels separately they found that in reverberation some vowels clustered more closely together on dimensions similar to 'F1 and F2' but a few vowels increased their differences in reverberation.…”

“…Vowel intelligibility in noise varies widely between talkers and is strongly influenced by style of speech (Bradlow & Alexander, 2007;Ferguson, 2004;Ferguson & Kewley-Port, 2002;Payton, Uchanski, & Braida, 1994). Similarly, in reverberant conditions without supporting context, errors in the identification of both vowels (e.g., Nábêlek, Czyzewski, & Crowley, 1993;Nábêlek & Letowski, 1988;Nábêlek et al, 1996) and consonants (e.g., Cox, Alexander, & Gilmore, 1987;Nábêlek, Letowski, & Tucker, 1989) have been reported. However, studies have also shown that naturally spoken vowels can be highly identifiable in reverberation or noise alone (e.g., Nábêlek, 1988;Nábêlek & Dagenais, 1986;Nábêlek et al, 1996).…”

The effect of aging on identification of Mandarin consonants in normal and whisper registers

“…Furthermore, whispering lowered the intensity of consonants (Jovičić and Šarić, 2008). Several studies have demonstrated that reduced-intensity compromised speech perception (Gordon-Salant, 1986;Nábělek et al, 1996;Kennedy et al, 1998), especially in less ideal conditions. For example, Nábělek et al (1996) found that the reduction of intensity ranging between 1 and 15 dB affected the diphthong perceptions, particularly for listeners with hearing loss and in noise and reverberation conditions.…”

“…Some studies found that intensity had less direct impacts on consonant perception (Zeng and Turner, 1990;Scharenborg and Janse, 2012), but other studies showed that intensity had interactive effects with other factors in phoneme perception. For example, Nábělek et al (1996) found the transition with high intensity facilitated the perception of diphthongs in older adults, especially in less ideal conditions. Another possible reason is that the energy distribution of these two fricatives is homogeneous throughout the spectrum which makes them perceptually confusing with other aspirated plosives.…”