Motor learning in visuomotor adaptation tasks results from both explicit and implicit processes, each responding differently to an error signal. Although the motor output side of these processes has been extensively studied, the visual input side is relatively unknown. We investigated if and how depth perception affects the computation of error information by explicit and implicit motor learning. Two groups of participants made reaching movements to bring a virtual cursor to a target in the frontoparallel plane. The Delayed group was allowed to reaim and their feedback was delayed to emphasize explicit learning, whereas the camped group received task-irrelevant clamped cursor feedback and continued to aim straight at the target to emphasize implicit adaptation. Both groups played this game in a highly detailed virtual environment (depth condition), leveraging a cover task of playing darts in a virtual tavern, and in an empty environment (no-depth condition). The delayed group showed an increase in error sensitivity under depth relative to no-depth. In contrast, the clamped group adapted to the same degree under both conditions. The movement kinematics of the delayed participants also changed under the depth condition, consistent with the target appearing more distant, unlike the Clamped group. A comparison of themore »
Judgments of Object Size and Distance across Different Virtual Reality Environments: A Preliminary Study
Emerging technologies offer the potential to expand the domain of the future workforce to extreme environments, such as outer space and alien terrains. To understand how humans navigate in such environments that lack familiar spatial cues this study examined spatial perception in three types of environments. The environments were simulated using virtual reality. We examined participants’ ability to estimate the size and distance of stimuli under conditions of minimal, moderate, or maximum visual cues, corresponding to an environment simulating outer space, an alien terrain, or a typical cityscape, respectively. The findings show underestimation of distance in both the maximum and the minimum visual cue environment but a tendency for overestimation of distance in the moderate environment. We further observed that depth estimation was substantially better in the minimum environment than in the other two environments. However, estimation of height was more accurate in the environment with maximum cues (cityscape) than the environment with minimum cues (outer space). More generally, our results suggest that familiar visual cues facilitated better estimation of size and distance than unfamiliar cues. In fact, the presence of unfamiliar, and perhaps misleading visual cues (characterizing the alien terrain environment), was more disruptive than an environment with a more »
- Award ID(s):
- 1928695
- Publication Date:
- NSF-PAR ID:
- 10356221
- Journal Name:
- Applied Sciences
- Volume:
- 11
- Issue:
- 23
- Page Range or eLocation-ID:
- 11510
- ISSN:
- 2076-3417
- Sponsoring Org:
- National Science Foundation
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