Motor Output Variability Impairs Driving Ability in Older Adults

Area of Science:

• Gerontology
• Motor Control
• Human Factors

Background:

• Aging is associated with functional declines, particularly in motor control and strength.
• These declines may impact complex tasks such as driving.
• This study investigates the specific role of motor control versus strength in age-related driving impairment.

Purpose of the Study:

• To determine if older adults exhibit impaired driving performance compared to young adults.
• To assess whether declines in motor control or strength are responsible for age-related driving deficits.
• To identify potential targets for interventions to improve driving safety in older populations.

Main Methods:

• Participants included young and older adults.
• Tasks involved maximum voluntary contractions, isolated ankle dorsiflexion tracking, and a reactive driving simulation.
• Motor control was assessed via force and position variability; driving performance included pedal errors and response times.

Main Results:

• Older adults demonstrated approximately 30% more impaired reactive driving performance.
• Increased motor output variability was observed in older adults during both isolated movements and the driving task.
• Impaired driving was significantly correlated with motor output variability, but not with muscle strength.

Conclusions:

• Age-related declines in motor control, not strength, significantly impair reactive driving ability.
• These findings highlight the importance of motor control in maintaining driving function in older adults.
• Rehabilitation strategies should prioritize enhancing motor control to improve driving-related capabilities in the elderly.