The Perception of the Vertical: XI. The Visual Vertical under Conflicting Visual and Acceleratory Factors

摘要

Four Ss made adjustments of the visual vertical in both presence and absence of a visual frame of reference under varying resultant acceleratory forces produced in a human centrifuge. In the absence of a visual frame of reference the subjectively accepted vertical to which S adjusted a target was aligned with the resultant acceleratory force. The adjustment was made whether or not the resultant force was aligned with S's body axis or acted at some angle to it. In the presence of a visual frame of reference which was in alignment with the resultant force S adjusted the visual vertical to a position which placed the target in alignment with the resultant and the main lines of the visual framework. In the presence of a visual frame of reference which is aligned with S's body axis and a resultant force which acts at some angle with S's body axis and the visual frame of reference S adjusts the visual vertical to a position of compromise. Neither visual or postural cues are accepted to the exclusion of the other. With increased intensity of the postural cues furnished by an acceleratory force the visual vertical is located relatively nearer to the vertical determined by the resultant force. (Author)