Effects of spatial and nonspatial cognitive activity on postural stability

Area of Science:

• Neuroscience
• Human Movement Science
• Cognitive Psychology

Background:

• Postural stability is crucial for daily activities.
• The interplay between cognitive load and postural control is not fully understood.
• Age-related changes may exacerbate cognitive-motor interference.

Purpose of the Study:

• To investigate if postural stability is automatically controlled or influenced by cognitive activity.
• To determine if cognitive task type and age affect postural control.
• To examine the impact of encoding versus maintenance phases of cognitive tasks on posture.

Main Methods:

• 70 participants (20-79 years) performed postural control tasks (standing still) while undertaking no cognitive task, a spatial memory task, or a nonspatial memory task.
• Cognitive tasks were also performed in a seated position for comparison.
• Postural sway was measured using a force platform; memory recall was assessed.

Main Results:

• Both spatial and nonspatial memory recall declined with age, irrespective of posture.
• Postural stability decreased with age, with the most significant decline during the spatial memory task.
• Participants were more stable during stimulus encoding but less stable during stimulus maintenance, particularly for the nonspatial task.

Conclusions:

• Postural stability is not purely automatic and is significantly modulated by concurrent cognitive activity.
• The impact of cognitive tasks on posture is complex, depending on age, task type (spatial vs. nonspatial), and processing phase (encoding vs. maintenance).
• These findings highlight age-related differences in cognitive-motor integration and the specific demands placed on the nervous system.