A, v, and AV discrimination of vowel duration (original) (raw)
Related papers
Visual discrimination of vowel duration
Scandinavian Journal of Psychology, 2009
Discrimination of vowel duration was explored with regard to discrimination threshold, error bias, and effects of modality and consonant context. A total of 122 normal-hearing participants were presented with disyllabic-like items such as /lal-lal/ or /mam-mam/ in which the lengths of the vowels were systematically varied and were asked to judge whether the first or second vowel was longer. Presentation was either visual, auditory, or audiovisual. Vowel duration differences varied in 24 steps: 12 with a longer first /a/ and 12 with a longer last /a/ (range: ±33-400 ms). Results: 50% JNDs were smaller than the lowest tested step size (33 ms); 75% JNDs were in the 33-66 ms range for all conditions but V /lal/, with a 75% JND at 66-100 ms. Errors were greatest for visual presentation and for /lal-lal/ tokens. There was an error bias towards reporting the first vowel as longer, and this was strongest for /mam-mam/ and when both vowels were short, possibly reflecting a sublinguistic processing strategy.
DURATION AFFECTS VOWEL PERCEPTION IN ESTONIAN AND FINNISH
Identification of vowels in quantity languages is usually considered to be independent of vowel duration since duration is used to realise the quantity oppositions and thus supposed to not be available as a cue for other features. To test the role of microdurational variations in vowel category perception in Estonian and Finnish listening experiments with synthetic stimuli were carried out, involving five vowel pairs along the close-open axis. The results show that in the case of high-mid vowel pairs vowel openness correlates positively with stimulus duration; in mid-low vowel pairs such correlation was only found for some of the Finnish subjects. We explain the observed difference between high-mid and mid-low pairs with the hypothesis that in case of shorter perceptual distances in vowel quality (high-mid area of vowel space) intrinsic duration plays the role of a secondary feature to enhance perceptual contrast between vowels, whereas in case of mid-low oppositions the perceptual distance is large enough to guarantee the necessary perceptual contrast by spectral features alone and vowel intrinsic duration as an additional cue is not needed.
The German vowel length contrast uses duration and quality (tense vs. lax) as phonetic cues. So far, the relative importance between these two cues has been assessed by identification tests. The present study extends this work by including discrimination tests assessing discrimination sensitivities to temporal and spectral changes in /u/-/o/ vowels embedded in disyllabic stimuli. Results favour vowel duration as the primary cue for vowel discrimination. Temporal discrimination showed a sensitivity maximum at the short-long boundary. Spectral discrimination did not reveal any sensitivity to lax-tense changes but only to changes between vowel types such as /u/ and /o/. It is concluded that vowel duration is used as the primary cue whereas vowel quality, the secondary cue, supports the contrast by increasing the perceptual distance between short and long vowels.
Transference or Desensitization? – A study of vowel spectra and duration
Some differences in speech perception by native and nonnative listeners can be accounted for as transference from a native language. Other differences appear to result from universal preferences. argues, more specifically, that non-native perceivers will prefer using some acoustic cues (e.g., duration), independent of whether they are used in the perceiver´s native language. In the case of second language (L2) vowel perception, duration may be used to categorize vowels when, from the non-native listener´s perspective, inadequate spectral cues are available. A testing ground for these accounts is found in the sound systems of American English and Norwegian, which have phonetically similar vowels which are qualitative contrasts in American English and quantitative contrasts in Norwegian. Results from two experiments support the desensitization hypothesis and suggest that vowel duration, perhaps as a universally preferred acoustic cue, may override the influence of native language transference.
What is and what is not under the control of the speaker: intrinsic vowel duration
Laboratory Phonology, 2009
This paper addresses the question of whether or not secondary features to sound contrasts are deliberately controlled by the speaker or if they result from implementational effects of the primary contrasting dimension. Specifically, we examine whether speakers control the variations in vowel duration that cooccur with height differences. Vowel durational differences between high and low vowels across changes in global timing were analyzed in Japanese, Catalan, and American English. The results for Catalan and American English show stable durational ratios between vowels differing in height across changes in rate, which suggests that vowel duration is specified and actively controlled by speakers as a cue to the vowel height contrast. In contrast, in Japanese the durational differences between high and low vowels can be explained by biomechanical factors.
Frontiers in Psychology, 2015
In some languages (such as Dutch), speakers produce duration differences between vowels, but it is unclear whether they also encode short versus long speech sounds into different phonological categories. To examine whether they have abstract representations for 'short' versus 'long' contrasts, we assessed Dutch listeners' perceptual sensitivity to duration in two vowel qualities: [a] and [A], as in the words maan 'moon' and man 'man,' which are realized with long and short duration respectively. If Dutch represents this phonetic durational difference as a 'short'-'long' contrast in its phonology, duration changes in [a] and [A] should elicit similar neural responses [specifically, the mismatch negativity (MMN)]. However, we found that duration changes evoked larger MMN amplitude for [a] than for [A]. This finding indicates that duration is phonemically relevant for the maan-vowel that is represented as 'long,' while it is not phonemically specified for the man-vowel. We argue that speakers who in speech production distinguish a given vowel pair on the basis of duration may not necessarily encode this durational distinction as a binary 'short'-'long' contrast in their phonological lexicon.