Benjamin R. Kunz

Evidence for Motor Simulation in Imagined Locomotion.

A series of experiments examined the role of the motor system in imagined movement, finding a strong relationship between imagined walking performance and the biomechanical information available during actual walking. Experiments 1 through 4 established the finding that real and imagined locomotion differ in absolute walking time. We then tested whether executed actions could provide a basis for imagined walking rate using 2 approaches. Experiments 5 and 6 used a perceptual-motor recalibration paradigm, finding that after physically walking in a treadmill virtual reality environment, actors recalibrated the time to imagine walking to a previously viewed target. This finding mirrors previous perceptual-motor recalibration work measuring actual walking to previously viewed targets. Experiments 7 and 8 used a dual-task paradigm in which actions performed concurrently with imagined walking increased the similarity between real and imagined walking time, but only when they were biomechanically consistent with the act of walking. The striking influence of biomechanical information on imagined locomotion provides evidence for shared motor systems in imagined and executed movements and is also directly relevant to the mechanisms involved in egocentric spatial updating of environmental layout.

Revisiting the effect of quality of graphics on distance judgments in virtual environments: A comparison of verbal reports and blind walking

In immersive virtual environments, judgments of perceived egocentric distance are significantly underestimated, as compared with accurate performance in the real world. Two experiments assessed the influence of graphics quality on two distinct estimates of distance, a visually directed walking task and verbal reports. Experiment 1 demonstrated a similar underestimation of distances walked to previously viewed targets in both low- and high-quality virtual classrooms. In Experiment 2, participants’ verbal judgments underestimated target distances in both graphics quality environments but were more accurate in the high-quality environment, consistent with the subjective impression that high-quality environments seem larger. Contrary to previous results, we suggest that quality of graphics does influence judgments of distance, but only for verbal reports. This behavioral dissociation has implications beyond the context of virtual environments and may reflect a differential use of cues and context for verbal reports and visually directed walking.

Does Perceptual-Motor Calibration Generalize across Two Different Forms of Locomotion? Investigations of Walking and Wheelchairs

The relationship between biomechanical action and perception of self-motion during walking is typically consistent and well-learned but also adaptable. This perceptual-motor coupling can be recalibrated by creating a mismatch between the visual information for self-motion and walking speed. Perceptual-motor recalibration of locomotion has been demonstrated through effects on subsequent walking without vision, showing that learned perceptual-motor coupling influences a dynamic representation of ones spatial position during walking. Our present studies test whether recalibration of wheelchair locomotion, a novel form of locomotion for typically walking individuals, similarly influences subsequent wheelchair locomotion. Furthermore, we test whether adaptation to the pairing of visual information for self-motion during one form of locomotion transfers to a different locomotion modality. We find strong effects of perceptual-motor recalibration for matched locomotion modalities – walking/walking and wheeling/wheeling. Transfer across incongruent locomotion modalities showed weak recalibration effects. The results have implications both for theories of perceptual-motor calibration mechanisms and their effects on spatial orientation, as well as for practical applications in training and rehabilitation.

Perception and action

The phrase perception and action is used widely but in diverse ways in the context of the relationship between perceptual and motor processes. This review describes and integrates five perspectives on perception and action which rely on both neurophysiological and behavioral levels of analysis. The two visual systems view proposes dissociable but interactive systems for conscious processing of objects/space and the visual control of action. The integrative view proposes tightly calibrated but flexible systems for perception and motor control in spatial representation. The embodied view posits that action underlies perception, involving common coding or motor simulation systems, and examines the relationship between action observation, imitation, and the understanding of intention. The ecological view emphasizes environmental information and affordances in perception. The functional view defines the relationship between perception, action planning, and semantics in goal-directed actions. Although some of these views/approaches differ in significant ways, their shared emphasis on the importance of action in perception serves as a useful unifying framework. WIREs Cogn Sci 2010 1 800-810 For further resources related to this article, please visit the WIREs website.

Testing the Mechanisms Underlying Improved Distance Judgments in Virtual Environments

Virtual environments (VEs) presented via head-mounted displays are typically perceived as smaller in scale than intended. Visual–motor experience in VEs can reduce this underestimation of distance, though the mechanisms underlying this improved accuracy of distance estimates are unknown. To address this question, we created a mismatch between biomechanical and visual indicators of self-movement within the VE, and assessed the effect on distance and size judgments. Our results suggest that visual–motor feedback influences subsequent distance judgments by recalibrating perceptual–motor relationships, but we found no evidence that perceived size, which was substantially underestimated, changed as a function of this feedback. In contrast to recent studies that suggest that feedback in VEs causes a broad rescaling of virtual space, our results are consistent with a visual–motor recalibration account for much of the improvement in distance judgments following VE experience.

Visual capture influences body-based indications of visual extent

Visual information regarding limb location can override proprioceptive information when there is conflict between the two—a phenomenon referred to as visual capture. In three experiments, we employed the “mirror illusion,” in which the perceived location of one’s hand is influenced by the visual information specified by the mirror reflection of the other hand, to test whether visual capture influences body-based indications of the extent of objects. Participants viewed their visible hand and its reflection in a mirror after the unseen hand was positioned at one of four locations on a tabletop. The unseen hand’s location appeared to be the same distance from the mirror as the visible hand’s location. After viewing the visible hand and its reflection while simultaneously performing simple finger movements with both hands, participants viewed a block and had to move their unseen hand to a position that would allow them to grasp the block between their two hands. Movements of the unseen hand relative to the visible hand were biased by the visual information, reflecting errors in moved hand position given visual–proprioceptive conflict. In Experiment 1, visual capture influenced the indications of object extent for objects within reach and aligned with the viewer’s midline. Experiments 2 and 3 extended these findings to indications of extent for objects outside the viewer’s reach (Experiment 2) and misaligned with the viewer’s midline (Experiment 3). These results suggest that visual body information has a generalizable effect on actions used to indicate space perception that extends beyond egocentric spatial localization tasks.

Is self-promotion evaluated more positively if it is accurate? Reexamining the role of accuracy and modesty on the perception of self-promotion

Abstract The present research sought to conceptually replicate and extend previous research showing that accurate self-promotional claims were associated with more favorable interpersonal evaluations than inaccurate claims, but that modest self-claims were evaluated most favorably. Across two experiments we found consistent evidence that a self-promotional claim paired with information that substantiates the claim is associated with more favorable interpersonal evaluations compared to when the claim is unsubstantiated. Despite proposed generational increases in narcissism and public venues for self-promotion, we found that that modest claims are evaluated even more positively than self-promotional claims. The discussion emphasizes the contribution of these findings to an understanding of the consequences of self-promotion.

Decoupling the Biomechanics of Locomotion and the Direction of Spatial Updating During Blind-Walking Tasks

updating (targets at 3, 4.5, & 6 meters) • Experiment 2: Decoupling walking direction and direction of spatial updating during backward walking (targets at 3, 4.5, & 6 meters) • Experiment 3: Decoupling walking direction and direction of spatial updating during backward walking (targets at 2, 4.5, & 7 meters) Decoupling the Biomechanics of Locomotion and the Direction of Spatial Updating During Blind-walking Tasks