Abstract
Aims and Objectives: The autonomic nervous system plays an important role in homeostasis and organismic recreation, control of immune function, inflammation, and bone growth. It also regulates blood pressure and orthostasis via vagal and sympathetic pathways. Besides recording of heart rate variability (HRV), which characterizes medium (1–5 min) and long term (circadian) autonomic tone or modulation, no gentle tests of short-term autonomic reactivity and control are available. In 1976 Nogier described a short time cardiovascular response (“Réflexe Auriculo Cardiaque”, RAC) which could be used to investigate short term autonomic reactions without changing system characteristics and thus being repeatable in short intervals. In this paper, we investigated the possible application of the Nogier reaction as a micro-test for the identification of a disturbed sensitivity or reactivity of the autonomic nervous system.Methods: We statistically analyzed cardiovascular signals derived during the application of small repeated stimuli utilizing methods of signal averaging to characterize the physiological background. Specifically, the Nogier reaction was investigated using simultaneous recordings of ECG, pulse waves, and respiration.Results: Significant fast (delay 1–5 s) and slower (delay 6–12 s) cardio-autonomic responses to different stimuli which characterize short term were observed. From time characteristics and type of signals where they occur we deduce that fast changes observed in heart rate are vagal reactions to the small stimuli whereas slower changes observed in pulse waves stem from sympathetic nervous system responses.Conclusions: The investigated autonomic micro-test opens the possibility to differentially investigate both limbs of the autonomic nervous system with minimal stimuli. It can be performed within seconds and does not change the set point of the system in opposition to less subtle tests such as Valsalva maneuver. Therefore, it is well-suited for quick, repeated measurements of autonomic nervous system reactivity.
Highlights
Most cells in the body react to signals of the autonomic nervous system
We further investigated the possible application of the Nogier reaction testing for the identification of functional disorders evoked by a disturbed sensitivity or reactivity of the autonomic nervous system
A clear baseline and amplitude modulating effect of respiration is visible in ECG and pulse recordings; a reason why the timing of stimuli in an irregular way is important
Summary
Most cells in the body react to signals of the autonomic nervous system. This explains the importance of this unconscious part of our nervous system for homeostatic regulation and hemodynamic balance. The time needed to obtain reliable values for HRV has been found between 5 min and 24 h, which is rather long if questions related to the patient autonomic reactions need to be answered fast For this reason, shorter, repeatable tests, which allow a rapid micro-testing of the ANS response to different stimuli should be investigated. Searching for a suitable test for the organismic response to acupuncture, Nogier discovered a cardiovascular reaction, which he could trigger by slightly stimulating certain points mechanically on the human ear (Nogier, 1972) He called it “réflexe auriculo cardiaque” or RAC (Oleson, 2002) without being able to give sufficient physiological explanation or an autonomic regulatory background. Medical doctors utilizing the Nogier reaction report that even minor disturbances of the autonomic nervous system can be observed
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call