Role of noise in human walking in the absence of orientational cues

• Published in: Physica. D 2022-12, Vol.442, p.133535, Article 133535
• Main Authors: Bod’ová, Katarína, Kollár, Richard, Miglierini, Mário
• Format: Article
• Language: English
• Subjects: Correlated random walk; Orientation; Randomness
• ISSN: 0167-2789; 1872-8022
• DOI: 10.1016/j.physd.2022.133535

Intrinsic noise is an integral component of human walk. We study its role in a model system of walking without orientational cues. Our experiments confirm veering walking patterns that we model by a stochastic mean reverting process involving walkers’ bias and noise. The model analysis reveals three parameter regimes corresponding to three scaling regimes of the first passage time of the full angular rotation of the walker: those whose dynamics is dominated by an angular noise, those dominated by an equilibrium angular bias, and those randomly drifting about their initial walking angle. However, our experimental subjects belong only to the first two groups. We also show that faster walkers have a smaller angular noise but the angular bias is not correlated with the walker speed. The level of angular noise is approximately uniform across the studied population. We also propose a simplified experimental protocol that allows us to approximately infer some of the model parameters from a coarse data set. Finally, a combination of the protocol with our model reveals that walkers with a small angular bias perform optimally in walking straight if their angular noise is small while performance of walkers with high angular bias improves if it is combined with the higher level of angular noise observed in our experiments.