Complexity, Regularity and Non-Linear Behavior in Human Eye Movements: Analyzing the Dynamics of Gaze in Virtual Sailing Programs

Abstract

The non-linear analysis of the behavior of biological signals in humans is studied from different scientific disciplines. The aim of this study was to analyze the possible non-linear behavior present in eye movements during eye-tracking tasks in simulated sailing. Thirty young sailors were selected. Fuzzy entropy and detrended fluctuation analyses were applied to quantify the regularity and complexity of eye movements. The results show that neither experience nor ranking affect the regularity or the complexity of eye movement positions or velocities. Younger age is related to more regular visual behavior. At younger ages, eye positions present more complex behavior. Eye positions show more complex behavior than eye velocities. This complexity would allow for a more functional exploration of the environment by sailors. Eye movement velocity presents the greatest irregularity, with significantly higher values than eye movement position. This irregularity would facilitate the visual perception of the environment. All these findings could be related to the sailors’ functional behavior, based on complexity and stability, which has been associated with the ability of human beings to adapt to the environment.

Visuomotor control dynamics of quiet standing under single and dual task conditions in younger and older adults

“…Fixations are defined as periods where the gaze rests on an area and is the period in which visual sensory input is attained, whereas, saccades are the rapid movements between fixations during which visual input is suppressed [23,27]. On the other hand the complexity of the gaze path has been used to investigate neural visuomotor control strategies [28][29][30], and the coupling of gaze and sway complexity to understand postural control mechanisms in tracking tasks [31,32], however this relationship has not been examined during quiet standing. An increase in gaze complexity represents greater visual exploration to increase the amount of information gained about the visual field [28,29].…”

“…On the other hand the complexity of the gaze path has been used to investigate neural visuomotor control strategies [28][29][30], and the coupling of gaze and sway complexity to understand postural control mechanisms in tracking tasks [31,32], however this relationship has not been examined during quiet standing. An increase in gaze complexity represents greater visual exploration to increase the amount of information gained about the visual field [28,29]. The effects of ageing on gaze complexity during quiet standing balance tasks have not been investigated.…”

Multivariate Multiscale Cosine Similarity Entropy and Its Application to Examine Circularity Properties in Division Algebras

“…The non-circularity manifests itself through a degree of correlation and power imbalance of the system channels, which can be reflected in a scatter plot as the inclined angle and dispersed degree of the distribution. The long-range correlation of a time series measured by multiscale entropy reflects the influence of past states on the generation of future signals [ 31 ], while the correlation of a multi-channel system is a measure of association among channels, a summary of dependence strength for multivariate systems, and a feature that could reflect the structural richness of the system [ 32 , 33 ]. A strongly correlated system is expected to show a high structural complexity, while a less correlated system would approach the performance of WGN to give a low structural complexity.…”