Postural adjustment errors during lateral step initiation in older and younger adults

Area of Science:

• Gerontology
• Neuroscience
• Biomechanics

Background:

• Age-related cognitive and motor declines are significant.
• Executive functions, like response inhibition, are crucial for complex motor tasks.
• Understanding age differences in voluntary stepping is vital for fall prevention.

Purpose of the Study:

• To investigate age-related differences in voluntary lateral step initiation.
• To examine the impact of varying response inhibition demands on stepping performance.
• To correlate stepping performance with clinical balance and executive function tests.

Main Methods:

• Seventy older adults (70-94 years) and twenty younger adults (21-58 years) participated.
• Participants performed visually cued lateral step initiation tasks with increasing inhibition complexity.
• Postural adjustments and step latencies were measured using ground reaction forces.

Main Results:

• Older adults showed greater step behavior variability and more postural adjustment errors than younger adults.
• Older adults exhibited longer step initiation latencies, which increased more with higher inhibition demands.
• Stepping task performance correlated more strongly with clinical balance tests than executive function tests.

Conclusions:

• Older adults experience significant challenges with response inhibition during voluntary stepping.
• Age-related deficits in executive control impact the ability to adjust postural responses and initiate steps accurately.
• Clinical balance assessments may better reflect age-related motor control deficits in stepping than executive function tests.