A note on voice timing and the evolution of connected speech

Area of Science:

• Linguistics
• Phonetics
• Speech Science
• Evolutionary Biology

Background:

• Voice is a fundamental aspect of human communication across all languages.
• The temporal organization of speech, particularly voice timing, may hold evolutionary significance.
• Information theory provides a framework for analyzing optimal signal timing.

Purpose of the Study:

• To investigate whether voice timing in connected speech is optimized according to information theory principles.
• To determine if voicing occupies approximately 50% of total speaking time.
• To explore the evolutionary implications of observed voice timing proportions.

Main Methods:

• Utilized Laryngograph (EGG) signals for precise voice timing analysis.
• Analyzed speech data from native speakers of 8 different languages.
• Included a sample of 56 speakers of British English.

Main Results:

• Average voice timing proportions were found to be 51% and 52%.
• These measured proportions closely approximate the theoretical ideal of 50% voicing.
• Consistent results were observed across diverse linguistic backgrounds.

Conclusions:

• The findings support the hypothesis that voice timing in speech has evolved towards an information-theoretically optimal state.
• The near-50% voicing proportion may represent an efficient balance for speech production and perception.
• This study provides empirical evidence for evolutionary pressures shaping the temporal dynamics of human voice.