This study investigated when the Bayesian cue combination of piloting and path integration occurs in human homing behaviors. The Bayesian cue combination was hypothesized to occur in estimating the home location or self-localization. In Experiment 1, the participants learned the locations of 5 objects (1 located at the learning position) in the presence of distal landmarks before walking a 2-leg path without viewing the landmarks and objects. At the end of the path, the participants indicated the original locations of the objects in 4 cue conditions: (a) path integration only, (b) landmarks only where the participants were disoriented and the landmarks reappeared, (c) both path integration and the reappearing landmarks, and (d) path integration and conflicting landmarks rotated 45°. The participants’ heading, position, and homing estimations were calculated. The ratio of the length of the second leg to that of the first leg was manipulated to be 0.5, 1, or 2. The results showed evidence of the Bayesian cue combination for heading estimates in all leg ratios, and for homing estimates in a small leg ratio (0.5) but not in a large leg ratio (2). The following experiments replicated the results of the Bayesian cue combination for heading but not for homing estimates for the large leg ratio (2) when participants did a typical homing task without learning the locations of objects (Experiment 2) and when proximal landmarks replaced distal landmarks (Experiments 3–4). These findings suggest that the Bayesian cue combination occurs in self-localization prior to homing.

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Older adults typically perform worse on spatial navigation tasks, although whether this is due to degradation of memory or an impairment in using specific strategies has yet to be determined. An issue with some past studies is that older adults are tested on desktop-based virtual reality: a technology many report lacking familiarity with. Even when controlling for familiarity, these paradigms reduce the information-rich, three-dimensional experience of navigating to a simple two-dimensional task that utilizes a mouse and keyboard (or joystick) as means for ambulation. Here, we utilize a wireless head-mounted display and free ambulation to create a fully immersive virtual Morris water maze in which we compare the navigation of older and younger adults. Older and younger adults learned the locations of hidden targets from same and different start points. Across different conditions tested, older adults remembered target locations less precisely compared to younger adults. Importantly, however, they performed comparably from the same viewpoint as a switched viewpoint, suggesting that they could generalize their memory for the location of a hidden target given a new point of view. When we implicitly moved one of the distal cues to determine whether older adults used an allocentric (multiple landmarks) or beaconing (single landmark) strategy to remember the hidden target, both older and younger adults showed comparable degrees of reliance on allocentric and beacon cues. These findings support the hypothesis that while older adults have less precise spatial memories, they maintain the ability to utilize various strategies when navigating.

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