We investigated the boundaries between imagery, memory, and perception by measuring gaze during retrieved versus imagined visual information. Eye fixations during recall were bound to the location at which a specific stimulus was encoded. However, eye position information generalized to novel objects of the same category that had not been seen before. For example, encoding an image of a dog in a specific location enhanced the likelihood of looking at the same location during subsequent mental imagery of other mammals. The results suggest that eye movements can also be launched by abstract representations of categories and not exclusively by a single episode or a specific visual exemplar.

The role of eye movements in mental imagery and visual memory is typically investigated by presenting stimuli or scenes on a two-dimensional (2D) computer screen. When questioned about objects that had previously been presented on-screen, people gaze back to the location of the stimuli, even though those regions are blank during retrieval. It remains unclear whether this behavior is limited to a highly controlled experimental setting using 2D screens or whether it also occurs in a more naturalistic setting. The present study aims to overcome this shortcoming. Three-dimensional (3D) objects were presented along a circular path in an immersive virtual room. During retrieval, participants were given two tasks: to visualize the objects, which they had encoded before, and to evaluate a statement about visual details of the object. We observed longer fixation duration in the area, on which the object was previously displayed, when compared to other possible target locations. However, in 89% of the time, participants fixated none of the predefined areas. On the one hand, this shows that looking at nothing may be overestimated in 2D screen-based paradigm, on the other hand, the looking at nothing effect was still present in the 3D immersive virtual reality setting, and thus it extends external validity of previous findings. Eye movements during retrieval reinstate spatial information of previously inspected stimuli.

Head-mounted displays enable social interactions in immersive virtual environments. However, it is yet unclear whether the technology is also suitable for collaborative work between remote group members. Previous research comparing group performance in nonimmersive computer-mediated communication and face-to-face (FtF) interaction yielded inconsistent results. For this reason, we set out to compare multiuser immersive virtual reality (IVR), video conferencing (VC), and FtF interaction in a group decision task. Furthermore, we examined whether the conditions differed with respect to cognitive load and social presence. Using the hidden profile paradigm, we tested 174 participants in a fictional personnel selection case. Discussion quality in IVR did not differ from VC and FtF interaction. All conditions showed the typical bias for discussing information that was provided for all participants (i.e., shared information) compared with information that was only disclosed to individual participants (i.e., unshared information). Furthermore, we found that IVR groups showed the same probability of solving the task correctly. Social presence in IVR was reduced compared with FtF interaction; however, we found no differences in cognitive load. In sum, our results imply that IVR can effectuate efficient group behavior in a modern working environment that is characterized by a growing demand for remote collaboration.

No abstract

During recall of visual information people tend to move their eyes even though there is nothing to see. Previous studies indicated that such eye movements are related to the spatial location of previously seen items on 2D screens, but they also showed that eye movement behavior varies significantly across individuals. The reason for these differences remains unclear. In the present study we used immersive virtual reality to investigate how individual tendencies to process and represent visual information contribute to eye fixation patterns in visual imagery of previously inspected objects in three-dimensional (3D) space. We show that participants also look back to relevant locations when they are free to move in 3D space. Furthermore, we found that looking back to relevant locations depends on individual differences in visual object imagery abilities. We suggest that object visualizers rely less on spatial information because they tend to process and represent the visual information in terms of color and shape rather than in terms of spatial layout. This finding indicates that eye movements during imagery are subject to individual strategies, and the immersive setting in 3D space made individual differences more likely to unfold.