Do disfluencies increase with age? Evidence from a sequential corpus study of disfluencies

Area of Science:

• Cognitive Psychology
• Neuroscience of Aging
• Speech Production

Background:

• Speech disfluencies offer insights into cognitive processes underlying speech production.
• Previous research on age-related changes in speech fluency is minimal and contradictory.
• Longitudinal data on individual changes in disfluency rates over time is lacking.

Purpose of the Study:

• To investigate how speech disfluency rates change across the lifespan in older adults.
• To determine if older age is associated with increased speech disfluencies.
• To examine the relationship between age-related speech changes and disfluency production.

Main Methods:

• Analysis of 325 recorded interviews from 91 individuals across a lifespan (ages 20-94).
• Utilized a sequential design with a longitudinal component to track changes over time.
• Assessed various disfluency types, including word repetitions, pauses, and repairs.

Main Results:

• Older age was associated with slower speech rate and increased word repetitions.
• No significant association was found between older age and filled pauses (e.g., 'uh', 'um') or repairs.
• Age-related changes in speech rate and complexity predicted disfluency production over the lifespan.

Conclusions:

• While age itself is not a strong predictor of all disfluencies, it influences speech rate and complexity in some individuals.
• These age-related speech modifications, in turn, predict the production of disfluencies throughout life.
• Findings help reconcile inconsistencies in aging and speech literature, paving the way for future research on cognitive mechanisms in healthy aging.