People naturally tend to walk to the left

An international study led by the University of Navarra has found that people exhibit a subtle yet consistent tendency to lean to the left when walking. conducted in collaboration with researchers from Waseda University and the University of Tokyo (Japan), as well as Shanghai University (China), and published in Nature Communications, shows that this individual inclination influences the way crowds spontaneously organise themselves and could help improve models used to manage pedestrian flows in crowded environments

The findings identify an intrinsic locomotor bias -a predisposition in movement direction- that helps explain some of the collective patterns observed in groups of pedestrians. The study challenges the idea that such behaviours arise exclusively from social norms or individual interactions, offering a new perspective on how certain collective phenomena emerge. In the longer term, this knowledge could contribute to the design of safer, more comfortable, and more efficient public spaces.

Until now, scientists have largely attributed the spontaneous organisation of crowds to interactions between individuals, collision-avoidance behaviours, social conventions governing pedestrian movement, such as keeping to the right or left depending on the country, and physical features of the environment, including walls and spatial boundaries. However, this study suggests that some of these behaviours may originate from individual predispositions that exist before any social interaction takes place. "For decades, we have assumed that these collective patterns emerged solely from interactions between pedestrians. Our work shows that a significant part of these patterns does not arise only when people come together as a group, but is already inherent to the individual," notes Iñaki Echeverría, researcher in Physics and Applied Mathematics at the University of Navarra and first author of the paper.

Researchers found that human movement is not entirely random. When asked to walk, participants showed a subtle but consistent tendency to veer in a counterclockwise direction, both indoors and in open spaces. Although this preference is small at the individual level, its effect becomes amplified when hundreds or thousands of people are involved, generating collective patterns that can be observed on a large scale. "Not every individual displays this preference, but a large majority tend to move in a counterclockwise direction. This inclination ultimately determines the direction adopted by the group as a whole and gives rise to visible collective patterns," explains Echeverría.

The counterclockwise tendency extends beyond cultural norms and the environment
To test traditional test , the team conducted a large-scale experimental campaign over several years in Spain and Japan. Comparing the two countries allowed them to analyze whether the phenomenon depended on how pedestrians try to avoid collisions while walking, since in both countries people tend to move and dodge in opposite directions. The trials included groups of adults walking in controlled spaces, schoolchildren moving freely in an open playground, Education , and participants walking individually.

One of the most significant findings was that the tendency persisted even when factors traditionally considered responsible were absent. It was observed in young children who had not yet fully internalised many social norms related to pedestrian movement, in open spaces without walls or obstacles, and in countries with different circulation habits. "We wanted to determine whether the phenomenon depended on cultural norms, interactions with the environment, or pedestrian avoidance strategies. Our results indicate that none of these factors alone can fully explain what we observed," says Iker Zuriguel, Professor of Applied Physics at the University of Navarra and one of the study's senior authors.

Experiments involving individuals walking alone further confirmed that the directional preference exists at the individual level, ruling out the possibility that it is a property that emerges only when people form part of a group. The researchers also examined factors related to laterality, including handedness, dominant foot and eye dominance, but found no evidence that these variables explain the observed behaviour.

Designing spaces tailored to the way people move

Beyond advancing our understanding of human behaviour, the study could have practical applications in areas such as urban mobility and the management of large crowds. The researchers were able to reproduce mathematically the patterns observed in large groups using only information obtained from individuals walking alone, reinforcing the idea that some collective dynamics can be understood through shared individual characteristics.

This knowledge may prove useful in settings with high concentrations of people, such as airports, railway stations, shopping centres and sports venues, where models are increasingly used to optimise movement and reduce congestion. "A better understanding of the factors that influence the way we move allows us to develop more accurate models of pedestrian behaviour in shared spaces. This information could help design more efficient infrastructure and create environments that are better adapted to the way people move in everyday life," adds Zuriguel.

The authors emphasise that social interactions and environmental factors remain key elements in understanding crowd behaviour. However, "the results suggest that individual predispositions also play an important role in the emergence of collective movement patterns. Furthermore, the study raises new questions about the biological origins of these tendencies, since similar phenomena have been observed in other animal species, from schools of fish to insect colonies," concludes Echeverría.