On the dynamics of spatial updating

Most of our knowledge on the human neural bases of spatial updating comes from fMRI studies in which recumbent participants moved in virtual environments. As a result, little is known about the dynamic of spatial updating during real body motion. Here, we exploited the high temporal resolution of electroencephalography (EEG) to investigate the dynamics of cortical activation in a spatial updating task where participants had to remember their initial orientation while they were passively rotated about their vertical axis in the dark. After the rotations, the participants pointed towards their initial orientation. We contrasted the EEG signals with those recorded in a control condition in which participants had no cognitive task to perform during body rotations. We found that the amplitude of the P1N1 complex of the rotation-evoked potential (RotEPs) (recorded over the vertex) was significantly greater in the Updating task. The analyses of the cortical current in the source space revealed that the main significant task-related cortical activities started during the N1P2 interval (136-303 ms after rotation onset). They were essentially localised in the temporal and frontal (supplementary motor complex, dorsolateral prefrontal cortex, anterior prefrontal cortex) regions. During this time-window, the right superior posterior parietal cortex (PPC) also showed significant task-related activities. The increased activation of the PPC became bilateral over the P2N2 component (303-470 ms after rotation onset). In this late interval, the cuneus and precuneus started to show significant task-related activities. Together, the present results are consistent with the general scheme that the first task-related cortical activities during spatial updating are related to the encoding of spatial goals and to the storing of spatial information in working memory. These activities would precede those involved in higher order processes also relevant for updating body orientation during rotations linked to the egocentric and visual representations of the environment.

Lean to Fly: Leaning-Based Embodied Flying can Improve Performance and User Experience in 3D Navigation

When users in virtual reality cannot physically walk and self-motions are instead only visually simulated, spatial updating is often impaired. In this paper, we report on a study that investigated if HeadJoystick, an embodied leaning-based flying interface, could improve performance in a 3D navigational search task that relies on maintaining situational awareness and spatial updating in VR. We compared it to Gamepad, a standard flying interface. For both interfaces, participants were seated on a swivel chair and controlled simulated rotations by physically rotating. They either leaned (forward/backward, right/left, up/down) or used the Gamepad thumbsticks for simulated translation. In a gamified 3D navigational search task, participants had to find eight balls within 5 min. Those balls were hidden amongst 16 randomly positioned boxes in a dark environment devoid of any landmarks. Compared to the Gamepad, participants collected more balls using the HeadJoystick. It also minimized the distance travelled, motion sickness, and mental task demand. Moreover, the HeadJoystick was rated better in terms of ease of use, controllability, learnability, overall usability, and self-motion perception. However, participants rated HeadJoystick could be more physically fatiguing after a long use. Overall, participants felt more engaged with HeadJoystick, enjoyed it more, and preferred it. Together, this provides evidence that leaning-based interfaces like HeadJoystick can provide an affordable and effective alternative for flying in VR and potentially telepresence drones.

Processing symmetry between visual and auditory spatial representations in updating working memory

Updating spatial representations in visual and auditory working memory relies on common processes, and the modalities should compete for attentional resources. The present study examined the relative dominance of memory updating using incompatible spatial information conveyed from two different cue modalities. Participants maneuvered a designated target on a matrix surface according to visual or auditory stimuli that were simultaneously presented, to identify a terminal location. Prior to the navigation task, the relative perceptual salience of the visual cues was manipulated to be equal, superior, or inferior to the auditory cues. The results demonstrated that visual and auditory inputs competed for attentional resources such that visual/auditory guidance was impaired by incongruent cues delivered from the other modality. Although visual dominance was favored in working memory navigation on average, stimuli of relatively high salience interfered with or facilitated other stimuli regardless of modality, demonstrating the similarity of updating processes in visual and auditory spatial working memory. Furthermore, processing asymmetry can be identified during the encoding of sensory inputs into working memory representations. The present results suggest that auditory spatial updating is comparable to visual spatial updating in that salient stimuli receive a high priority when selecting inputs and are used when tracking spatial representations.

Impaired Attentional Processing During Parabolic Flight

Previous studies suggest that altered gravity levels during parabolic flight maneuvers affect spatial updating. Little is known about the impact of the experimental setting and psychological stressors associated with parabolic flight experiments on attentional processes. To address this gap, we investigated the level of alertness, selective and sustained attention in 1 and 0 g using a Go/No-Go Continuous Performance Task. We also identified several parameters associated with the experimental set-up of a parabolic flight that could be expected to affect attentional processing. These included the use of scopolamine, sleep quality prior to the flight day, participant’s stress level as well as mood and anxiety state before and after the parabolic flight. We observed a deterioration in attentional processing prior to the first parabola that was further aggravated in weightlessness and returned to baseline after the last parabola. Reaction Time, Hit and False Alarm Rate were moderately correlated with self-reported anxiety state, but not cortisol levels or emotional states. The use of scopolamine had minor effects on Reaction Time. Our results confirm previous studies reporting impairments of cognitive performance in 0 g, and highlight important aspects that should be considered for the design of behavioral research experiments in future parabolic flight campaigns.

Visuo-Locomotive Update in the Wild. The Role of (Un)Familiarity in Choice of Navigation Strategy, and its Application in Computational Spatial Design

We study active human visuo-locomotive experience in everyday navigation from the viewpoints of environmental familiarity, embodied reorientation, and (sensorimotor) spatial update. Following a naturalistic, in situ, embodied multimodal behaviour analysis method, we conclude that familiar users rely on environmental cues as a navigation-aid and exhibit proactive decision-making, whereas unfamiliar users rely on manifest cues, are late in decision-making, and show no sign of sensorimotor spatial update. Qualitative analysis reveals that both groups are able to sketch-map their route and consider path integration: i.e., conscious spatial representation updating was possible but not preferred during active navigation. Overall, the experimental task did not trigger automatic or reflexlike spatial updating, as subjects preferred strategies involving memory of perceptual cues and available manifest cues instead of relying on motor simulation and continuous spatial update. Rooted in the behavioural outcomes, we also position applications in computational modelling of navigation within cognitive technologies for architectural design synthesis.

The Effectiveness of Locomotion Interfaces Depends on Self-Motion Cues, Environmental Cues, and the Individual

The proliferation of locomotion interfaces for virtual reality necessitates a framework for predicting and evaluating navigational success. Spatial updating---the process of mentally updating one's self-location during locomotion---is a core component of navigation, is easy to measure, and is sensitive to common elements of locomotion interfaces. This paper highlights three factors that influence spatial updating: body-based self-motion cues, environmental cues, and characteristics of the individual. The concordance framework, which characterizes locomotion interfaces based on agreement between body movement and movement through the environment, serves as a useful starting point for understanding the effectiveness of locomotion interfaces for enabling accurate navigation.