Nonlinearities of Heart Rate Variability in Junior High School Students Under Mathematics Anxiety

Heart rate variability (HRV) is commonly assessed using linear methods; however, there is increasing evidence of potential nonlinear aspects in HRV. This study aimed to investigate nonlinear dynamics in Junior High School students with and without math anxiety. We hypothesized that there would be differences in the irregularity and nonlinearity of RR fluctuation time series between students with and without math anxiety. The study encompassed two stages with a sample of 34 first-grade students: an exam stage (EXAM) conducted during the examination period and a regular class day stage (NO EXAM). The Abbreviated Mathematics Anxiety Scale (AMAS) and the multiscale entropy (MSE) of the RR time series were assessed in both stages. Our findings indicated a decrease in the irregularity and nonlinearity of the RR time series in students during the EXAM stage compared to the NO EXAM stage. Additionally, we observed that the AMAS scores were higher in the EXAM group compared to the NO EXAM group. These results suggest that math anxiety may impact specific nonlinear characteristics of the cardiovascular system and may be associated with modifications in cardiac autonomic function. Future investigations should explore alternative entropy-based methods to examine HRV in students experiencing different anxiety-inducing situations.