Impact of simulated target blur on the preparation and execution of aiming movements

Previous findings have highlighted how visual information directly influences the preparation and control of aiming movements. However, less is understood about the influence of a degraded visual context such as target blur. Participants aimed as quickly and accurately as possible to clear or blurred virtual targets using a stylus on a digitizing board, which could translate movements to a cursor on the screen. The time it took before initiating the movement indicated the preparation for movement, while the time spent within the movement was considered a manifestation of additional online control. The results showed a more prolonged time to initiate movements for blurred compared to clear targets, but no influence for movement time, or end-point accuracy and precision. The observed adaptation in movement preparation may reflect an initial uncertainty surrounding the visual context; namely, the visual target characteristics that are typically needed for precise and accurate aiming. Meanwhile, the absence of any influence within the movement itself reflects the processing of the coarse and dynamic visual characteristics of the limb, which was independent of the degraded visual context of the target. These findings may contribute further insights toward low vision and the possible functional adaptations