Updating headings in 3D navigation

Abstract

The current study investigated to what extent humans can encode spatial relations between different surfaces (i.e., floor, walls, and ceiling) in a 3D space and extend their headings on the floor to other surfaces when locomoting to walls (pitch 90○) and the ceiling (pitch 180○). In immersive virtual reality environments, participants first learned a layout of objects on the ground. They then navigated to testing planes: south (or north) walls facing Up, or the ceiling via walls facing North (or South). Participants locomoted to the walls with pitch rotations indicated by visual and idiothetic cues (Experiment 1) and only by visual cues (Experiment 2) and to the ceiling with visual pitch rotations only (Experiment 3). Using the memory of objects’ locations, they either reproduced the object layout on the testing plane or did a Judgements of Relative Direction (JRD) task (“imagine standing at object A, facing B, point to C”) with imagined headings of south and north on the ground. The results showed that participants who locomoted onto the wall with idiothetic cues showed a better performance in JRD for an imagined heading from which their physical heading was extended (e.g., imagined heading of North at the north wall). In addition, the participants who reproduced the layout of objects on the ceiling from a perspective extended from the ground also showed a sensorimotor alignment effect predicted by an extended heading. These results indicate that humans encode spatial relations between different surfaces and extend headings via pitch rotations three-dimensionally, especially with idiothetic cues.

The influence of environmental geometry and spatial symmetry on spatial updating during locomotion.

“…However, for L-I = 0, there was no difference between A-I = 0 and A-I = 180 conditions (t(12) = 0.52, p = 0.61), suggesting no sensorimotor alignment effect. This is consistent with some previous studies showing a smaller sensorimotor alignment effect for the imagined heading of the learning orientation (e.g., Du et al, 2021;Mou, McNamara, et al, 2004).…”

“…This experiment used a within-subject design (see Table 3) and the conditions were defined in terms of two independent variables following previous studies (Du et al, 2021; Mou, Biocca, et al, 2004; Mou, McNamara, et al, 2004; Riecke & McNamara, 2017) to separate the sensorimotor alignment effect solely attributed to spatial updating from the learning orientation effect (Table 1). One independent variable was the angular distance between the actual and imagined perspectives in the JRD task (i.e., Actual-Imagined or A-I) and was manipulated to be 0° or 180° (i.e., the actual and imagined perspectives were aligned or misaligned).…”

“…Because the sensorimotor alignment effects solely attributed to spatial updating are already separated from the learning orientation effect, there is no requirement of a neutral imagined perspective as a baseline to test the sensorimotor alignment effects as well as the learning orientation effect. Mou, McNamara et al (2004; see also Du et al, 2021; Riecke & McNamara, 2017) used this method and demonstrated both sensorimotor alignment effects and learning orientation effects independently. Mou et al (2008; see also Mou, Biocca, et al, 2004) also used this method and demonstrated only the learning orientation effect but no sensorimotor alignment effects when participants believed that the object array was stabilized relative to their bodies when they turned.…”