Biology subjects

Feliciani, C.

Publications and source records attributed to Feliciani, C..

3 recordsLinked to original sources

bioRxiv2023

Robust spatial self-organization in crowds of asynchronous pedestrians

Similar to other animal groups, human crowds exhibit a variety of self-organized collective behaviors. Spontaneous formation of unidirectional lanes in bidirectional pedestrian flows is one of the most striking examples of self-organization in human crowds. In addition, previous experimental studies have suggested that stepping among pedestrians is spontaneously synchronized over time. However, those studies have primarily focused on one-dimensional, single-file crowds, limiting our understanding of temporal stepping patterns in crowds with more freedom of movement and their relationship to spatial patterns of organization. Here, we conducted experiments of bidirectional pedestrian flows (24 pedestrians in each group) and investigated the relationship between collective footsteps and self-organized lane formation by tracking each individual trajectory as well as foot-stepping kinematics. We found that, unlike previous studies, pedestrians did not spontaneously align their steps unless there was an external auditory cue to follow. Moreover, we found that footstep synchronization generated by external cues disturbed the flexibility of pedestrians lateral movements, increased potential collision risks, and narrowed the formed lanes, suggesting structural instability in the spatial organization. These results imply that, without external cues, pedestrians marching out of step with each other can efficiently self-organize into robust structures. Understanding how asynchronous individuals contribute to ordered collective behavior has potential applications for promoting efficient crowd management and will inform theoretical models for human and other animal collective behavior with asynchronous positional updates.

animal behavior and cognition↗

bioRxiv2022

Spontaneous behavioral coordination between pedestrians emerges through mutual anticipation rather than mutual gaze

Human activities are often performed together between two or more persons, as if they are a complex dance. Threading through a crowd is a striking example of such coordinated actions. Behavioral coordination should help to reduce head-on collisions, smooth a pedestrians pathway through a crowd, and promote a self-organization process. Although mutual anticipation between pedestrians would be a candidate for underlying mechanisms of behavioral coordination, it remains largely unexplored, especially in terms of visual information. Here, we investigated the effects of mutual anticipation between a pair of pedestrians performing simple avoidance tasks using a combination of motion- and eye-tracking systems. We found that pedestrians in a baseline condition spontaneously coordinated their walking speed and angle until passing each other. Visually distracting one of the pedestrians decreased the level of behavioral coordination, indicating that spontaneous coordination emerges through mutual anticipation. Importantly, blocking the pedestrians gaze information alone did not alter their walking, clearly ruling out the assumption that mutual gaze impacts pedestrian anticipation behavior. Moreover, eye-movement analysis demonstrated that the direction of a pedestrians gaze changed depending on the uncertainty of the oncoming pedestrians motion and that pedestrians tend to look ahead toward the ultimate passing direction before they actually walked in that direction. We propose that body motion cues may be sufficient and available for implicit negotiation on potential future motions. Our findings should be useful in various fields, including research on improvisational motions, pedestrian transportation, and robotic navigation.

animal behavior and cognition↗

bioRxiv2020

Mutual anticipation can contribute to self-organization in human crowds

Human crowds provide paradigmatic examples of collective behavior emerging through self-organization. Although the underlying interaction has been considered to obey the distance-dependent law, resembling physical particle systems, recent findings emphasized that pedestrian motions are fundamentally influenced by the anticipated future positions of their neighbors rather than their current positions. Therefore, anticipatory interaction may play a crucial role in collective patterning. However, whether and how individual anticipation functionally benefits the group is not well-understood. We suggest that collective patterning in human crowds is promoted by anticipatory path-seeking behavior resulting in a scale-free movement pattern, called the Levy walk. In our experiments of lane formation, a striking example of self-organized patterning in human crowds where people moving in opposite directions spontaneously segregate into several unidirectional lanes, we manipulated some pedestrians ability to anticipate by having them type on a mobile phone while walking. The manipulation slowed overall walking speeds and delayed the onset of global patterning, and the distracted pedestrians sometimes failed to achieve their usual walking strategy. Moreover, we observed that the delay of global patterning depends on decisions made by pedestrians who were moving toward the distracted ones and had no choice but to take sudden large steps, presumably because of difficulty in anticipating the motions of their counterparts. These results imply that mutual anticipation between pedestrians facilitates efficient transition to emergent patterning in situations where nobody within a crowd is distracted. Our findings may contribute to efficient crowd management and inform future models of self-organizing systems.

animal behavior and cognition↗