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Clinical and Experimental Evaluation of Sympatho-Vagal Interaction: Power Spectral Analysis of Heart Rate and Arterial Pressure Variabilities
Published in Irving H. Zucker, Joseph P. Gilmore, Reflex Control of the Circulation, 2020
Alberto Malliani, Massimo Pagani, Federico Lombardi, Sergio Cerutti
Mayer waves are known to be increased in amplitude by various manipulations such as hypotensive hemorrhage (Preiss and Polosa, 1974) or increases in subarachnoid pressure (Kaminski et al., 1970), thus suggesting that they might reflect different functional states. As it will be seen, the approach that we shall propose is largely based on the fact that the tonic increase in sympathetic activity appears capable in numerous different conditions of increasing a third-order rhythm affecting various cardiovascular variables.
Haemodynamics: flow, pressure and resistance
Published in Neil Herring, David J. Paterson, Levick's Introduction to Cardiovascular Physiology, 2018
Neil Herring, David J. Paterson
In addition to respiration-related oscillations, arterial pressure may show regular oscillations at a lower frequency of ~6/min (0.1 Hz), called Mayer waves. These are due to synchronous oscillations in sympathetic vasoconstrictor activity. The sympathetic oscillation is thought to result from a slow feedback by the baroreflex (Chapter 16).
Autonomic nervous system assessment using heart rate variability
Published in Acta Cardiologica, 2023
Jean-Marie Grégoire, Cédric Gilon, Stéphane Carlier, Hugues Bersini
The interpretation of the LF band (0.04–0.15 Hz) is more complex. Sympathetically mediated blood pressure oscillations (Mayer waves) are slower than respiration and are reflected in the HRV spectrum [31]. As a result, the LF band indirectly represents at least part of the adrenergic activity. It is related to the baroreceptor reflex. Thus, part of the LFs comes from vagal activity because this reflex is mediated by the vagus nerve. As a result, vagal or adrenergic participation in the LF band is highly variable depending on the position and activity of the subjects. This variable participation complicates interpretation and invalidates the fact that LFs can be considered solely representative of adrenergic activity. Eckberg also suggested that central mechanisms may play a role in addition to the baroreflex [32]. Thus, the interpretation of LFs as solely representative of adrenergic activity should be avoided.
Comparison of Functional Connectivity during Visual-Motor Illusion, Observation, and Motor Execution
Published in Journal of Motor Behavior, 2022
Katsuya Sakai, Junpei Tanabe, Keisuke Goto, Ken Kumai, Yumi Ikeda
We removed the oxy-Hb data that contained a low signal-to-noise ratio at several channels due to failures in source and detector placement (Niu et al., 2012) and data that included visually clear motion artifacts using fNIRS. For the signal-to-noise ratio, we used the auto-adjustment function of fNIRS. The auto-adjustment function of fNIRS was set to minimize the noise. The data retrieved from fNIRS was analyzed using a custom written program in MATLAB (MATLAB R2019a; The Math Works Inc., Natick, United States of America, Ma, USA). The oxy-Hb also applied the 0.01–0.1 Hz band-pass filter to the fNIRS signals (Hramov et al., 2020; Yamazaki et al., 2020). This band-pass filter could remove the effect of physiological activities (i.e., Mayer wave, respiration, heartbeat) (Hramov et al., 2020; Yamazaki et al., 2020). Then, oxy-Hb data calculated the Pearson correlation coefficient (r) of all channel pairs time-series data. The r values were converted into Z scores using the Fisher’s r-to-z transformation (Sakai, Goto, et al., 2020).
Low cardiac vagal tone index by heart rate variability differentiates bipolar from major depression
Published in The World Journal of Biological Psychiatry, 2019
Brandon Hage, Briana Britton, David Daniels, Keri Heilman, Stephen W. Porges, Angelos Halaris
Heart rate variability (HRV) is defined as the variation between heartbeats over time and involves input from both the sympathetic and parasympathetic divisions of the ANS. Short recordings on an electrocardiogram (ECG) produce two primary patterns of oscillation that correspond to HRV (Heathers 2014). One periodic process occurs between about 2 and 8 s (approximately one breath cycle in the general population), which corresponds to a frequency between approximately 0.12 and 0.4 Hz. This oscillation coincides with a physiological phenomenon known as respiratory sinus arrhythmia (RSA), which is characterised by a spontaneous oscillation in the beat-to-beat heart rate pattern that occurs within the frequencies of spontaneous breathing. RSA provides an accurate estimate of cardiac vagal tone (Kamath and Fallen 1996). A second periodic process occurs between about 10 and 25 s, which corresponds to 0.04–0.10 Hz (low frequency, or LF-HRV). The pattern produced by this frequency band coincides with vascular rhythms and is often known as the Traube-Hering-Mayer wave (Eckberg 2000).