When vision is impaired, what should athletes focus on? The underlying mechanisms of human movement


Research demonstrates robust benefits of an external focus of attention and although the Constrained Action Hypothesis accounts for this phenomenon, traditional outcome measures are limited in progressing our understanding of underlying mechanisms here. The current study utilises 'vision' in addressing this. Literature advocates attentional as opposed to visual processes in accounting for external benefits and subsequently these mechanisms have been investigated independently. Aiming literature suggests the role of vision in executing accurate movements is twofold; firstly in planning movements (i.e. offline) and secondly in correcting errors during movement (i.e. online). The rationale for this study was to investigate visual feedback in the utilisation of offline/online processes under different attentional foci. Participants were randomised into four groups; internal full-vision (IF-FV), internal no-vision (EF-NF), external full-vision (EF-FV) and external no-vision (EF-NV). The task was a rapid aiming movement, performed over five experimental phases. Dependent measures included constant and variable error, movement time and within-participant standard deviation in distance travelled throughout the movement trajectory. A 4(group) x 4(distance travelled) ANOVA on variable error at retention revealed a distance travelled x group interaction. Whilst both the NV groups increased in variability as the movement progressed, this increase reduced during movement execution under IF but not EF conditions (reflective of online control in the IF not EF condition). When visual information wasn't available, participants adopting an IF were better able to process proprioceptive feedback to make movement adjustments online. Presumably, through an increased focus on the actual movement characteristics; something not afforded under EF conditions.