Original scientific paper

Nonlinear characteristics of temporal changes in cardiovascular activity

Ana Proroković orcid.org/0000-0003-1457-3515 ; Sveučilište u Zadru, Odjel za psihologiju
Matilda Nikolić ; Sveučilište u Zadru, Odjel za psihologiju

Abstract

Based on the results of previous studies that have investigated the dynamics of the cardiovascular system, it can be said that this system, among other things, has nonlinear characteristics. The main aim of this study was to investigate changes in the nonlinear dynamic of cardiac activity during the performance of psychomotor tasks with different information load (Fitts’ tapping).
The study included 40 healthy (with no cardiovascular disorders) participants who were approximately the same age (19 – 23 years). Their task was to perform psychomotor tasks with varying degrees of
information load. Tapping tasks were performed for 15 minutes (adjusted to the number of units of time series, which are sufficient for the planned analyses, a minimum of 1000 data).
The results showed that the cardiovascular system, regardless of the complexity of the performed psychomotor activities, has the characteristics of chaotic dynamics since all obtained largest Lyapunov
exponents were positive. The calculated correlation dimensions indicate that the system has a medium dimensionality. With increasing difficulty of Fitts’ tapping tasks, the correlation dimension has a tendency of reduction, and the percentage of recurrence and determinism shows a significant increase.

Keywords

nonlinear dynamics; cardiovascular system; largest Lyapunov exponent; correlation dimension

Hrčak ID:

133146

URI

https://hrcak.srce.hr/133146

Publication date:

14.1.2015.

Article data in other languages: croatian

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