Perception of Temporal and Spectral Information in French Vowels

Abstract

Perceptual effects of orthogonal variations in temporal and spectral information differentiating French /o/ and /o/ were examined. Although both parameters contribute to acoustic differentiation of /o/ and /o/, the phonetic and phonological structure of French suggests that duration might be a less important perceptual property in French than in languages like American English. Three 10-step /kot/-/kot/ continua were synthesized by systematically varying frequencies of the first two formants of the vowel nuclei. The three continua differed in vowel duration (140, 180, and 220 msec). Two perceptual tests, identification and 5-choice category rating, were presented to three listener groups: native French, native American English who had studied French, and native American English who did not know French. For both native American English groups, spectrally ambiguous vowels were identified and rated more often as /o/ when these vowels were long and as /o/ when short, thereby showing a trading relation between temporal and spectral information. In contrast, native French listeners showed little effect of duration in either perceptual task. Despite this perceptual insensitivity to duration, acoustic measurements showed that these French subjects' productions of /o/ and /o/ consistently maintained a duration difference. Results are interpreted to support the view that perceptual integration of the acoustic properties relevant to a phonemic contrast depends not only on covariation of the properties in the production of that contrast, but also on the prominence of this covariation in the language's phonological system.

The <i>loi de position</i> and the acoustics of French mid vowels

“…First, while close-mid round vowels have been shown to be longer than their open-mid counterparts in positions where they contrast in Standard French (e.g., côte [kot] vs. cote [kɔt]; see Gottfried & Beddor 1988), it is unclear whether this durational difference extends to contrastive unrounded mid vowels in Standard French (e.g., thé [te] vs. taie [tɛ]), and to French varieties where close-mid and open-mid vowels are in complementary distribution.…”

“…The loi de position can probably not be reduced to an increase in F1 while analyzing the centralizing of F2 for peripheral mid vowels as a by-product of this increase, due to the (Gottfried & Beddor 1988). Therefore durational targets must be specified for close-mid and open-mid vowels in this variety of French.…”

Bridging the Gap Between L2 Speech Perception Research and Phonological Theory

“…Gerrits (2001) has suggested that there is a possible problem with synthetic stimuli, in that they may be perceived differently from naturally produced stimuli, in the sense that subjects categorize natural stimuli more easily; but a more recent study (Nittrouer 2001) has shown that neither children nor adults are adversely affected by the use of synthetic stimuli, since synthetic and naturally produced exemplars of the English /s/-/S/ contrast were categorized equally well. The reason for using isolated vowels was that cue weighting studies that use CVC stimuli (Gottfried, 1984;Gottfried & Beddor, 1988;Strange, Akahane-Yamada, Kubo, Trent & Nishi, 2001) show contextual effects, i.e., vowels are perceived differently when presented in different consonantal environments. The use of isolated vowels avoids these effects and makes the listeners rely more on their abstract representation of the vowels at hand; the drawbacks of presenting isolated vowels are generally that cues deriving from the consonantal context are lost (but that may actually be an advantage in our case) and that an isolated /I/ sounds unnatural because this vowel never occurs utterance-finally in English (but a series of pilot studies revealed that subjects had no large bias against identifying /I/ in isolation).…”

“…Crosslinguistically, the attention paid to the cues that signal a contrast varies between adult speakers of different languages (Bradlow, 1995;Fox, Flege & Munro, 1995;Gottfried & Beddor, 1988). For instance, Gottfried & Beddor (1988) show that unlike American English speakers, for whom vowel contrasts involve duration in production as well as in perception, Parisian French speakers produce only small durational differences and do not use durational information at all when categorizing vowels. Developmentally, babies have to learn what aspects of the phonetic signal serve as cues in their language and how much importance to attach to each cue (Scobbie 1998).…”

Perception of suprasegmental structure in a non-native dialect

“…Thus, speakers of standard French show little sign of using temporal information in making vowel distinctions (Gottfried & Beddor, 1988), because standard French does not use temporal cues to distinguish vowels. Swiss French does, however, and speakers of Swiss French can make use of temporal information when distinguishing vowels (Miller & Grosjean, 1997).…”