Some effects of speaking rate on phonetic perception

Area of Science:

• Phonetics
• Speech Perception
• Psychoacoustics

Background:

• The perception of speech sounds is influenced by various acoustic cues.
• Speaking rate is a significant factor affecting phonetic perception, particularly the distinction between consonants like /b/ and /w/.

Purpose of the Study:

• To review studies investigating how variations in speaking rate affect the perception of syllable-initial consonants /b/ and /w/.
• To determine if listeners adjust their phonetic perception based on speaking rate when interpreting formant transition durations.

Main Methods:

• Analysis of listener performance in identifying /b/ vs. /w/ across different speaking rates.
• Examination of the role of formant transition duration as a cue for distinguishing /b/ and /w/.
• Investigation of how syllable duration and acoustic-phonetic structure signal speaking rate.

Main Results:

• Listeners consistently adjusted their interpretation of formant transition duration based on speaking rate.
• Longer transitions were perceived as /w/ at slower rates, while shorter transitions were perceived as /b/ at faster rates.
• This rate-dependent perception was observed even in pre-articulate infants, suggesting innate perceptual mechanisms.

Conclusions:

• Listeners exhibit perceptual constancy for consonant identification across varying speaking rates.
• The ability to adjust phonetic perception based on speaking rate appears to be an innate human capacity.
• Formant transition duration is a crucial cue for distinguishing /b/ and /w/, with its interpretation modulated by speech rate.