Individual locomotor bias drives counterclockwise motion in pedestrian crowds

Article https://doi.org/10.1038/s41467-026-73713-w Individual locomotor bias drives counterclockwise motion in pedestrian crowds Received: 29 April 2025 Check for updates 1234567890():,; 1234567890():,; Accepted: 14 May 2026 Iñaki Echeverría-Huarte 1 , Claudio Feliciani 2,3, Zhigang Shi 4, Katsuhiro Nishinari 2, Angel Sánchez 5,6, Angel Garcimartín 1 & Iker Zuriguel 1 Pedestrian walking behaviour is intrinsic to individuals, yet it is influenced by external factors such as obstacles and the degree of crowding. It is precisely in crowded scenarios that pedestrian interactions lead to collective motions, such as lane formation or waves. Recently, the spontaneous development of collective counterclockwise motion has been reported in both dense and sparse human assemblies. Here we present five experimental studies of this phenomenon conducted across diverse conditions in Spain and Japan, demonstrating that counterclockwise bias in roaming pedestrians is a robust and reproducible feature and originates from individual tendencies rather than from collective interactions. These findings challenge the traditional view that social dynamics shape pedestrian motion, highlighting the existence of an intrinsic locomotor bias. Anyone who has walked along a crowded street has probably noticed that pedestrians spontaneously self-organise into lanes, grouping with pairs that share the same direction of motion1–3. This phenomenon can be seen as an example of the crowd inducing individual behavioural changes that result in an overall benefit for the group, as lane formation reduces personal discomfort and minimises the risk of collision4. Another scenario in which collective patterns emerge is when a crowd exits through a narrow passage—so small that two people cannot pass through it simultaneously5. In this scenario, pedestrians naturally split into two alternating streams—one passing through the door’s right-hand side and the other through its left-hand side. This so-called zipper effect results in a more efficient evacuation than if they had simply formed a single file and exited the room through the centre of the door5,6. Interestingly, in both cases (cross-flow and bottleneck flow) selforganised structures form owing to individual collision-avoidance manoeuvres and an unspoken mutual communication between people7. In other words, a simple individual behaviour adopted independently by many people can result in a collective behaviour that is only indirectly the outcome of each individual’s action. This is what is called an emerging phenomenon, with examples in pedestrian dynamics extending to group oscillations8,9, stripes10,11, and waves12 observed in large, dense crowds. Remarkably, all these phenomena occur without any leader orchestrating them, and people are often not even aware of the pattern they are creating. Furthermore, it has been argued that, under some circumstances, a seemingly collective pattern is created (or strongly influenced) by biased preferences of the members of a crowd. For example, in most countries, the lanes described earlier tend to form to the right (in the sense of the march) as a result of a weak tendency for people to move rightwards when facing another pedestrian13. Similarly, it has recently been proposed that a slight preference among right handed people to turn left when facing a wall14 could underlie the emergence of collective counterclockwise (CCW) crowd motion, both in mosh pit dancing15 and when a crowd walks freely within an arena16. 1 Departamento de Física y Matemática Aplicada, Facultad de Ciencias, Universidad de Navarra, Pamplona, Spain. 2Department of Aeronautics and Astronautics, Graduate School of Engineering, The University of Tokyo, Tokyo, Japan. 3Waseda Institute for Advanced Study, Waseda University, Tokyo, Japan. 4 Business School, University of Shanghai for Science and Technology, Shanghai, China. 5Grupo Interdisciplinar de Sistemas Complejos (GISC), Departamento de Matemáticas, Universidad Carlos III de Madrid, Leganés, Spain. 6Instituto de Biocomputación y Física de Sistemas Complejos (BIFI), Universidad de e-mail: Zaragoza, Zaragoza, Spain. Nature Communications | (2026)17:4869 1 Article https://doi.org/10.1038/s41467-026-73713-w In contrast to this view, our study offers a different perspective on the origins of CCW motion. Through five carefully designed experimental campaigns conducted in diverse settings and across different countries, we have gathered evidence that challenges the conventional interpretation. Rather than being an emergent property driven by interpersonal interactions (possibly influenced by personal biases), our results indicate that the collective CCW motion is rooted in inherent individual tendencies. As we shall see, we observed that CCW motion consistently emerged even when all pedestrians roaming in an enclosed space were left-handed or when their turning preference was to the right (Fig. 1a). We also ruled out the possibility that the cause is associated with interactions with boundaries by conducting experiments in an open space (Fig. 1b). Another plausible hypothesis related to interpersonal interactions—in particular, to avoidance manoeuvres —suggested that such manoeuvres might trigger CCW rotation in the same way as they lead to right-side lane formation in counterflows. However, the results from experiments in Japan (Fig. 1c), where lanes tend to form to the left side (in the sense of the march) during counterflows, refuted this idea. Moreover, we excluded a strong effect of social or acquired influences (such as the CCW sense of motion in athletics tracks) by analysing the dynamics of children during free play at a Japanese nursery17. We also found no evidence that an unspoken social norm is responsible for CCW motion by showing that the survey responses do not reveal a clear norm. Finally, we analysed single pedestrians walking alone in an enclosure, confirming that this symmetry-breaking phenomenon is caused by individual behaviour, most likely biologically rooted. Our contribution is thus twofold. First, we provide experimental evidence that the CCW bias is robust across diverse experimental settings and is reproducible across the two countries represented in our samples (Spain and Japan), with potential implications for urban planning and crowd management. Second, our findings demonstrate that this phenomenon arises from individual behaviour rather than collectively emerging due to pedestrian-pedestrian or pedestrianboundary interactions. Then, we ruled out some of the most obvious individual symmetry breaking factors –such as handedness, footedness, and eye dominance– thus leaving the precise origins of this intriguing behaviour open for further investigation. Results In this section, we present our results on the statistical properties of motion observed in each experiment. By analysing the patterns and a differences across scenarios and countries, we aim to uncover the underlying (...truncated)