LAUSR

Background Gait initiation is an automatized motor program. However, it can vary depending on attentional resources. Executive attention, an attentional process involved in cognitive control of action, could play a role in movement preparation. Objective to evaluate how executive control may modulate gait initiation. Methods The Attention Network Test was used to control the influence of executive attention on both gait initiation kinetic characteristics and associated brain cortical activity. Thirty healthy subjects performed this test, in standard (seated) and gait initiation tasks. Reaction times were measured for both tasks in each condition (conflict resolution or not); step execution time and anticipatory postural adjustments were also recorded for the initiation task. Cortical activity was recorded via a 128-channel electro-encephalogram. Event-related potential (P300 component) and event-related spectral perturbation between 4 and 30 Hz were analysed, after the target presentation, according to conflict resolution or not. Results As reaction time measured at upper limbs, step execution time was significantly longer during conflict resolution. This effect was concomitant with a larger proportion of anticipatory postural adjustments errors, leading to an increase in duration of postural preparation. Event-related potentials analyses revealed a modulation of parietal P300’s amplitude and latency (the amplitude was lower and the latency was longer in case of conflict resolution). Event-related spectral perturbation analyses showed a posterior alpha- and beta-band desynchronisation after the target presentation, both in standard and initiation conditions. Posterior alpha and beta oscillations were also modulated by executive control in both conditions. Significance Our results showed that the executive attentionalcomponent has an influence on gait initiation, by eliciting more errors in motor programming. These errors were associated with parietal cortical modulation involving posterior attentional networks during movement preparation.