Reiko A. YAMADA and Yoh'ichi TOHKURA
The Effect of Experiment Variables on
the Perception of American English /r,l/
for Japanese Listeners
- Response Categories, Classification
of Subjects, and Stimulus Range -
Abstract:The effects of experiment variables associated with the experiment tasks on the identification
of American English /r,l/ for native speakers of Japanese are investigated. The three variables studied are:
response categories, classification of subjects, and stimulus ranges. Through experiments using
synthesized American English /rait-lait/ series and naturally spoken stimuli, all three variables are
revealed to affect the experiment results for Japanese listeners. The effects of these variables clarify some
of the perceptual characteristics of /r,l/ for Japanese listeners. In the first experiment designed to
determine the effects of response categories, it is suggested that Japanese listeners identify some of the
stimuli on the/r-l/ continuum as /w/. In the second experiment, differences in perceiving synthesized
stimuli are discussed by classifying the Japanese listeners. The results show a positive correlation
between the perception of synthesized stimuli and naturally spoken /r,l,w/. Japanese listeners well able
to identify naturally spoken/r,l,w/ perceive the synthetic stimulus series categorically but they still have
three categories, /r/,/w/ and/l/on the series. In the third experiment, the stimulus range shows a striking
effect on the identification results for Japanese listeners. The /r/ and /l/ perception is strongly affected
by the stimulus range, whilge the /w/ perception less so. This indicates that Japanese listeners tend to make
a relative judgement between /r/ and /l/. The experiment variables studied in this paper are of great
importance when considering modelling the acquisition process of non-native phonemes.