Author: James A J Heathers1
Affiliation: <sup>1</sup>Psychophysiology Group, Department of Psychology, University of Sydney Sydney, NSW, Australia.
Conference/Journal: Front Physiol
Date published: 2014 May 7
Other:
Volume ID: 5 , Pages: 177 , Special Notes: doi: 10.3389/fphys.2014.00177. , Word Count: 141
Frequency analysis of the electrocardiographic RR interval is a common method of quantifying autonomic outflow by measuring the beat-to-beat modulation of the heart (heart rate variability; HRV). This review identifies a series of problems with the methods of doing so-the interpretation of low-frequency spectral power, the multiple use of equivalent normalized low frequency (LFnu), high frequency (HFnu) and ratio (LF/HF) terms, and the lack of control over extraneous variables, and reviews research in the calendar year 2012 to determine their prevalence and severity. Results support the mathematical equivalency of ratio units across studies, a reliance on those variables to explain autonomic outflow, and insufficient control of critical experimental variables. Research measurement of HRV has a substantial need for general methodological improvement.
KEYWORDS: autonomic nervous system; heart rate variability; parasympathetic nervous system; sympathetic nervous system; sympatho-vagal balance.
PMID: 24847279 PMCID: PMC4019878 DOI: 10.3389/fphys.2014.00177