Complexity of Heart Rate During More and Less Differentiated Behaviors

Abstract

Autonomic nervous system is the main way for the brain–body coordination, of which mode can be evaluated by dynamics of heart rate variability (HRV). HRV analysis is used for evaluation of different psychological states (stress, arousal, cognitive control etc.), which can be considered as characteristics of behavior that formed at different stages of ontogeny. We investigated whether HRV differs between the early-formed (less differentiated) behavior and the later-formed (more differentiated) behavior. Heart rate was recorded in 33 healthy subjects (mathematical specialists). Participants performed two tests which included sentences with mathematical terms and sentences with common current used words. They had to add one missing word in each sentence. Sample entropy as a measure quantifying the complexity of time series was used to analyze HRV. Complexity of heart rate was significantly higher in the mathematical test performance when participants actualized the later-formed behavior.