Improving Dual-Task Control With a Posture-Second Strategy in Early-Stage Parkinson Disease

Area of Science:

• Neuroscience
• Motor Control
• Clinical Neurology

Background:

• Parkinson disease (PD) often impairs motor control and dual-tasking abilities.
• Early-stage PD patients without overt postural symptoms may still experience subtle deficits in postural control during complex tasks.

Purpose of the Study:

• To investigate the impact of task prioritization on dual-task performance in early-stage PD patients.
• To determine if a 'posture-second' strategy benefits individuals with PD and no apparent postural issues.

Main Methods:

• A cross-sectional study involving 16 early-stage PD patients without clinical postural symptoms.
• Participants performed a force-matching task on a mobile platform under single- and dual-task conditions.
• Task prioritization was manipulated by instructing participants to focus on either the postural or the force-matching task first.

Main Results:

• The 'posture-second' strategy led to reduced dual-task change (DTC) in posture and force errors compared to the 'posture-first' strategy.
• However, the 'posture-second' strategy showed a greater DTC in reaction time (RT).
• Posture approximate entropy (ApEn) showed increased DTC under the 'posture-second' strategy.

Conclusions:

• The 'posture-second' strategy may be beneficial for early-stage PD patients without postural symptoms.
• This strategy could mitigate negative dual-tasking effects and promote postural automaticity.
• Findings challenge traditional task prioritization recommendations for this patient group.