The dual-task automated walking performance in people with Parkinson\'s disease (PD) is affected by their gait disturbances and impaired executive functions. Currently, the relationship between brain activity related to inhibitory control, executive functions, and dual-task walking performance in people with PD is not well understood. Therefore, this study aims to investigate the significance of different executive function domains on gait stability in healthy older adults and people with PD; whether brain activation related to inhibitory control is associated with gait stability in healthy older adults and people with PD.