Evidence for mora timing in Japanese

Area of Science:

• Phonetics and Phonology
• Linguistic Timing
• Acoustic Analysis of Speech

Background:

• Linguistic descriptions of Japanese classify it as a 'mora-timed' language.
• Traditional Japanese language pedagogy asserts that moras possess constant durations.
• This study investigates the acoustic reality of mora timing in Japanese.

Purpose of the Study:

• To test hypotheses regarding mora timing in Japanese speech.
• To examine the mechanisms underlying mora duration constancy.
• To investigate how variations in segment and syllable structure affect timing.

Main Methods:

• Four experiments were conducted to analyze segmental timing in Japanese.
• Measurements of word duration were correlated with the number of moras.
• Analysis focused on how segment durations are adjusted within syllables.

Main Results:

• Word duration increases by consistent increments with each additional mora.
• The duration of a word closely adheres to a target duration based on mora count.
• Segments and adjacent moras are stretched or compressed to maintain mora timing.

Conclusions:

• Japanese speech timing is more flexible than the traditional mora-timing model suggests.
• Mechanisms exist to adjust segment and mora durations to meet overall timing targets.
• The duration of segments within syllables is modulated to preserve mora count consistency.