Training Japanese listeners to identify English /r/ and /l/. III. Long-term retention of new phonetic categories

Abstract

Monolingual speakers of Japanese were trained to identify English /r/ and /l/ using Logan et al.'s [J. Acoust. Soc. Am. 89, 874-886 (1991)] high-variability training procedure. Subjects' performance improved from the pretest to the post-test and during the 3 weeks of training. Performance during training varied as a function of talker and phonetic environment. Generalization accuracy to new words depended on the voice of the talker producing the /r/-/l/ contrast: Subjects were significantly more accurate when new words were produced by a familiar talker than when new words were produced by an unfamiliar talker. This difference could not be attributed to differences in intelligibility of the stimuli. Three and six months after the conclusion of training, subjects returned to the laboratory and were given the post-test and tests of generalization again. Performance was surprisingly good on each test after 3 months without any further training: Accuracy decreased only 2% from the post-test given at the end of training to the post-test given 3 months later. Similarly, no significant decrease in accuracy was observed for the tests of generalization. After 6 months without training, subjects' accuracy was still 4.5% above pretest levels. Performance on the tests of generalization did not decrease and significant differences were still observed between talkers. The present results suggest that the highvariability training paradigm encourages a long-term modification of listeners' phonetic perception. Changes in perception are brought about by shifts in selective attention to the acoustic cues that signal phonetic contrasts. These modifications in attention appear to be retrained over time, despite the fact that listeners are not exposed to the /r/-/l/ contrast in their native language environment.

Perceptual adaptation to non-native speech

“…For example, highly successful learning of the English /r/-/l/ contrast by Japanese listeners has been demonstrated following training with words that placed /r/ and /l/ in various phonetic environments as produced by various native talkers of English. This learning has been shown to generalize to untrained words and to novel talkers, to transfer to improved production of the contrast and to be retained for at least 6 months following initial training (Logan et al, 1991;Lively et al, 1993Lively et al, , 1994Yamada, 1993;Bradlow et al, 1997Bradlow et al, , 1999. Similarly successful learning has been demonstrated for other non-native contrasts following similar high-variability training procedures including training of English listeners on Chinese lexical tone contrasts (Wang, Spence, Jongman and Sereno, 1999;Wang, Jongman and Sereno, 2003), training of English and Japanese listeners on Hindi dental and retroflex stops (Pruitt, 1995), training English listeners on Japanese vowel length contrasts (Yamada, Yamada and Strange, 1996), training Chinese listeners on English word-final /t/ and /d/ (Flege, 1995), and training English listeners on various German vowel contrasts (Kingston, 2003).…”

Talker-specific learning in speech perception

“…Relatively few studies have been conducted on the role of perceptual learning in the perception of speech and language in adults (but see Lively, Logan, & Pisoni, 1993;Lively, Pisoni, Yamada, Tohkura, & Yamada, 1994;Logan, Lively, & Pisoni, 1991;Strange & Dittmann, 1984). Although the role of categorization in perceptual sensitivity has long intrigued psychologists (E. 1.…”

Perception of suprasegmental structure in a non-native dialect

“…Just as systematic training can enable listeners to acquire certain di$cult perceptual distinctions in segmental structure (Logan, Lively & Pisoni, 1991;Lively, Pisoni, Yamada, Tohkura & Yamada, 1994), so can explicit training in perception of suprasegmental distinctions be extremely e!ective in improving listeners' sensitivity (Wang, nagasa HLL or nagashi LHH). Thus, listeners could e!ectively exploit the cues to accent pattern available even in the "rst syllable of a word.…”