Abstract
In order to guide whole-body movements in the absence of visual feedback, one must dynamically update position as a function of movement. This process of spatial updating is thought to be automatic, and likely underlies accurate performance in tasks that involve blind-walking to goal locations. Walking to previously-viewed targets is accurate when the direction of spatial updating and direction of movement are consistent (Paquet et al., 2007). When biomechanical information is absent, as in imagined walking without overt movement, walking times are significantly underestimated compared to real walking times (Kunz et al., 2009). We further investigated the role of biomechanical information in spatial updating by decoupling the direction of locomotion and spatial updating in backward blind-walking. In a baseline experiment, participants viewed targets directly in front of or behind them and walked either forward or backward without vision to the targets while spatially updating in a manner consistent with their direction of movement. Participants were generally accurate in both forward and backward blind-walking, suggesting that participants spatially update in a manner consistent with their direction of movement, even for less common forms of locomotion, such as backward walking. In subsequent experiments, targets were always placed in front of participants. Participants either spatially updated while walking forward without vision to targets or walked backward away from targets while spatially updating in a manner consistent with forward walking, thereby spatially updating in a direction opposite their direction of movement. The accuracy of backward walking decreased when the biomechanics of locomotion were inconsistent with the direction of spatial updating. The results are consistent with previous findings that illustrate automatic spatial updating when walking without vision; spatial updating is less automatic and more effortful when there is a mismatch between the direction of locomotion and the direction of spatial updating.
Meeting abstract presented at VSS 2014