title: Effects of different stresses on cardiac autonomic control and cardiovascular coupling.
abstract: The objective of this study was to investigate the impacts of different stresses on time-varying autonomic reactivity and cardiovascular coupling. In total, 25 male subjects were recruited. RR intervals (RRI), systolic and diastolic blood pressure (SBP, DBP), stroke volume (SV), cardiac output (CO), and systemic vascular resistance (SVR) values were collected during rest, mental arithmetic task (MAT), and cold pressor test (CPT). Baroreflex sensitivity (BRS) was derived using the transfer function method. Continuous wavelet transformation of RRI was used to describe the time-variant patterns of autonomic neural activities. Wavelet cross correlation and phase synchronization were used to estimate the amplitude and phase coupling between RRI and SBP. MAT was characterized by increased heart rate (HR), SBP, DBP, and CO with decreased BRS attributable to prolonged parasympathetic withdrawal. Moreover, cardiovascular coupling was disrupted in MAT. These results indicated that baroreflex was depressed, and the top-down system started to take action under mental stress. In CPT, SBP, DBP, and SVR increased significantly, whereas HR and BRS remained unchanged. The increase of sympathetic activity was transient, and cardiovascular coupling did not change in CPT. Intriguingly, the frequency of the maximum cross-correlation coefficient in the low-frequency band (0.04-0.15 Hz) was significantly decreased in CPT, which may be due to the change of resonance frequency of the baroreflex loop.NEW & NOTEWORTHYThe study is the first to compare the time-variant pattern of autonomic nervous activities and cardiovascular coupling between the mental arithmetic task (MAT) and the cold pressor test (CPT). Our results demonstrated that MAT and CPT elicited different time-varying patterns of autonomic neural activities and cardiovascular synchronization. Both the amplitude and phase consistency of blood pressure and heart rate decreased in MAT. CPT may affect the harmonic frequency of the baroreflex loop.
authors.affiliation: Key Laboratory of Biomedical Information Engineering of Education Ministry, Xi'an Jiaotong University, Xi'an, China; and.
authors.forename: Lin
authors.initials: L
authors.lastname: Xie
authors.affiliation: Key Laboratory of Biomedical Information Engineering of Education Ministry, Xi'an Jiaotong University, Xi'an, China; and.
authors.forename: Binbin
authors.initials: B
authors.lastname: Liu
authors.affiliation: Key Laboratory of Biomedical Information Engineering of Education Ministry, Xi'an Jiaotong University, Xi'an, China; and.
authors.forename: Xiaoni
authors.initials: X
authors.lastname: Wang
authors.affiliation: Key Laboratory of Biomedical Information Engineering of Education Ministry, Xi'an Jiaotong University, Xi'an, China; and.
authors.forename: Mengqi
authors.initials: M
authors.lastname: Mei
authors.affiliation: Key Laboratory of Biomedical Information Engineering of Education Ministry, Xi'an Jiaotong University, Xi'an, China; and.
authors.forename: Mengjun
authors.initials: M
authors.lastname: Li
authors.affiliation: Department of Information Engineering, Officers College of CAPF, Chengdu, China.
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Yu
authors.affiliation: Key Laboratory of Biomedical Information Engineering of Education Ministry, Xi'an Jiaotong University, Xi'an, China; and zhangjb@mail.xjtu.edu.cn.
authors.forename: Jianbao
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000293:Adolescent; D000328:Adult; D001341:Autonomic Nervous System / Q000502:physiology*; D017704:Baroreflex / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology*; D002302:Cardiac Output / Q000502:physiology; D003071:Cognition / Q000502:physiology*; D003080:Cold Temperature; D025461:Feedback, Physiological / Q000502:physiology; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D013312:Stress, Physiological / Q000502:physiology*; D055815:Young Adult
keywords: autonomic nervous system; cardiovascular coupling; cold pressor test; continuous wavelet transform; mental stress