Contrary to expectations from earlier studies of dual-task motor performance, bilateral subthalamic deep brain stimulation may assist in maintaining temporal and spatial gait performance in Parkinson disease under cognitive dual-task conditions, a recent study found. Gait kinematics of 17 patients with advanced Parkinson disease who had undergone bilateral, subthalamic, deep brain stimulation were examined off medication under 3 stimulation states (bilateral, unilateral left, unilateral right) with and without a cognitive challenge, using an instrumented walkway system. Researchers found:

• Consistent with earlier studies, gait performance declined for all 6 measured parameters under cognitive dual-task conditions, independent of stimulation state.
• However, bilateral stimulation produced greater improvements in step length and double-limb support time than unilateral stimulation, and achieved similar performance for other gait parameters.