37 research outputs found
Thinking Outside the Body: An Advantage for Spatial Updating during Imagined Versus Physical Self-Rotation
Three studies examined effects of different response measures on spatial updating during self-rotation. In Experiment 1, participants located objects in an array with a pointer after physical self-rotation, imagined self-rotation, and a rotation condition in which they ignored superfluous sensorimotor signals. In line with previous research, updating performance was found to be superior in the physical self-rotation condition compared with the other 2. In Experiment 2, participants performed in identical movement conditions but located objects by verbal labeling rather than pointing. Within the verbal modality, an advantage for updating during imagined self-rotation was found. In Experiment 3, participants performed physical and imagined self-rotations only and used a pointing response offset from their physical reference frames. Performance was again superior during imagined self-rotations. The results suggest that it is not language processing per se that improves updating performance but rather a general reduction of the conflict between physical and projected egocentric reference frames
An Account of the Systematic Error in Judging What Is Reachable
An account of the postural determinants of perceived reachability is proposed to explain systematic overestimations of the distance at which an object is perceived to be reachable. In this account, these errors are due to a mapping of the limits of prehensile space onto a person\u27s perceived region of maximum stretchability, in the context of a whole-body engagement. In support of this account, 6 experiments on the judged reachability of both static and dynamic objects are reported. We tentatively conclude that the mental imagery of action is grounded and calibrated in reference to multiple skeletal degrees of behavioral freedom. Accordingly, this calibration is a source of systematic error in reachability judgments
Mapping the Zone of Eye-Height Utility for Seated and Standing Observers
In a series of experiments, we delimited a region within the vertical axis of space in which eye height (EH) information is used maximally to scale object heights, referred to as the zone of eye height utility (Wraga, 1999b Journal of Experimental Psychology, Human Perception and Performance 25 518-530). To test the lower limit of the zone, linear perspective (on the floor) was varied via introduction of a false perspective (FP) gradient while all sources of EH information except linear perspective were held constant. For seated (experiment 1a) observers, the FP gradient produced overestimations of height for rectangular objects up to 0.15 EH tall. This value was taken to be just outside the lower limit of the zone. This finding was replicated in a virtual environment, for both seated (experiment 1b) and standing (experiment 2) observers. For the upper limit of the zone, EH information itself was manipulated by lowering observers\u27 center of projection in a virtual scene. Lowering the effective EH of standing (experiment 3) and seated (experiment 4) observers produced corresponding overestimations of height for objects up to about 2.5 EH. This zone of approximately 0.20-2.5 EH suggests that the human visual system weights size information differentially, depending on its efficacy
Passive Tactile Feedback Facilitates Mental Rotation of Handheld Objects
Mental rotation of objects improves when passive tactile information for the rotating object accompanies the imagined rotation (Wraga, Creem, & Proffitt, 2000). We examined this phenomenon further using a within-subjects paradigm involving handheld objects. In Experiment 1, participants imagined rotating an unseen object placed on their upturned palms. The participants were faster at mental rotation when the object was rotated on their palm than when the object remained stationary. Experiment 2 tested whether the performance advantage would endure when the participants received tactile information for only the start- and endpoints of the rotation event. This manipulation did not improve performance, relative to a stationary control. Experiment 3 revealed that ambiguous tactile information, continuous with the rotation event but independent of object shape, actually degraded performance, relative to a stationary control. In Experiment 4, we found that continuous tactile rotation discrepant from imagined object movement also hindered performance, as compared with continuous tactile information aligned with imagined object movement. The findings suggest a tight coupling between tactile information specifying continuous object rotation and the corresponding internal representation of the rotating object. Copyright 2008 Psychonomic Society, Inc
Updating Displays after Imagined Object and Viewer Rotations
Six experiments compared spatial updating of an array after imagined rotations of the array versus viewer. Participants responded faster and made fewer errors in viewer tasks than in array tasks while positioned outside (Experiment 1) or inside (Experiment 2) the array. An apparent array advantage for updating objects rather than locations was attributable to participants imagining translations of single objects rather than rotations of the array (Experiment 3). Superior viewer performance persisted when the array was reduced to 1 object (Experiment 4); however, an object with a familiar configuration improved object performance somewhat (Experiment 5). Object performance reached near-viewer levels when rotations included haptic information for the turning object. The researchers discuss these findings in terms of the relative differences in which the human cognitive system transforms the spatial reference frames corresponding to each imagined rotation
The Influence of Spatial Reference Frames on Imagined Object-and vVewer Rotations
The human visual system can represent an object\u27s spatial structure with respect to multiple frames of reference. It can also utilize multiple reference frames to mentally transform such representations. Recent studies have shown that performance on some mental transformations is not equivalent: Imagined object rotations tend to be more difficult than imagined viewer rotations. We reviewed several related research domains to understand this discrepancy in terms of the different reference frames associated with each imagined movement. An examination of the mental rotation literature revealed that observers\u27 difficulties in predicting an object\u27s rotational outcome may stem from a general deficit with imagining the cohesive rotation of the object\u27s intrinsic frame. Such judgments are thus more reliant on supplementary information provided by other frames, such as the environmental frame. In contrast, as assessed in motor imagery and other studies, imagined rotations of the viewer\u27s relative frame are performed cohesively and are thus mostly immune to effects of other frames. © 1999 Elsevier Science B.V. All rights reserved
Imagining Physically Impossible Self-Rotations: Geometry is More Important than Gravity
Previous studies found that it is easier for observers to spatially update displays during imagined self-rotation versus array rotation. The present study examined whether either the physics of gravity or the geometric relationship between the viewer and array guided this self-rotation advantage. Experiments 1-3 preserved a real or imagined orthogonal relationship between the viewer and the array, requiring a rotation in the observer\u27s transverse plane. Despite imagined self-rotations that defied gravity, a viewer advantage remained. Without this orthogonal relationship (Experiment 4), the viewer advantage was lost. We suggest that efficient transformation of the egocentric reference frame relies on the representation of body-environment relations that allow rotation around the observer\u27s principal axis. This efficiency persists across different and conflicting physical and imagined postures. Copyright © 2001 Elsevier Science B.V
Neural Basis of Stereotype-Induced Shifts in Women\u27s Mental Rotation Performance
Recent negative focus on women\u27s academic abilities has fueled disputes over gender disparities in the sciences. The controversy derives, in part, from women\u27s relatively poorer performance in aptitude tests, many of which require skills of spatial reasoning. We used functional magnetic imaging to examine the neural structure underlying shifts in women\u27s performance of a spatial reasoning task induced by positive and negative stereotypes. Three groups of participants performed a task involving imagined rotations of the self. Prior to scanning, the positive stereotype group was exposed to a false but plausible stereotype of women\u27s superior perspective-taking abilities; the negative stereotype group was exposed to the pervasive stereotype that men outperform women on spatial tasks; and the control group received neutral information. The significantly poorer performance we found in the negative stereotype group corresponded to increased activation in brain regions associated with increased emotional load. In contrast, the significantly improved performance we found in the positive stereotype group was associated with increased activation in visual processing areas and, to a lesser degree, complex working memory processes. These findings suggest that stereotype messages affect the brain selectively, with positive messages producing relatively more efficient neural strategies than negative messages. © 2007 Oxford University Press
Spatial Updating of Virtual Displays During Self- and Display Rotation
In four experiments, we examined observers\u27 ability to locate objects in virtual displays while rotating to new perspectives. In Experiment 1, participants updated the locations of previously seen landmarks in a display while rotating themselves to new views (viewer task) or while rotating the display itself (display task). Updating was faster and more accurate in the viewer task than in the display task. In Experiment 2, we compared updating performance during active and passive self-rotation. Participants rotated themselves in a swivel chair (active task) or were rotated in the chair by the experimenter (passive task). A minimal advantage was found for the active task. In the final experiments, we tested similar manipulations with an asymmetrical display. In Experiment 3, updating during the viewer task was again superior to updating during the display task. In Experiment 4, we found no difference in updating between active and passive self-movement. These results are discussed in terms of differences in sources of extraretinal information available in each movement condition