The timing organization of phonological durational contrast is known to be one of
the most challenging areas in the acquisition of Japanese phonology (Sugito 1989;
Muraki and Nakaoka 1990; Han 1992; Toda 1994). This study examines the
acquisition of timing control and perceptual categorization of the durational contrast in
Japanese, and aims to contribute to second language acquisition theory from the
viewpoint of interlanguage phonology.
Acoustic techniques were used to investigate the mechanisms of learners' speech
perception and production. In order to capture the acquisition processes and the
developmental factors in the formation of interlanguage phonology, both crosssectional
and longitudinal experiments are conducted with different groups of learners
at various proficiency levels, and the results were compared with those of native
. speakers.
The processes such as first language transfer, overexaggeration and phonetic
approximation are observed in the learners' speech production. The acoustic
observation revealed what has been claimed as genetically innate Universal Grammar
(Chomsky and Halle 1968) pertaining to voice onset time, which is clearly observed in
Japanese native speakers speech, is not operative in beginning learners' speech
production. On the other hand, it is operative in advanced learners' speech which
shares similarities with that of native speakers. The experimental results reported in
this dissertation reveal crucial theoretical insufficiency concerning the "universal
principle". This supposedly universal theory concerning voice onset time, should not
be restricted to a specific language, runs into difficulties in explaining the reasons why
this property does not show up with learners' speech production during the initial
stages, but does show up later at more advanced stages (i.e. it is developmental, but
not universal)
