Collection 2003


Written by Andrei MIU, Renata HEILMAN, Raluca ANTON, Cristina INDREI, Tiberiu KRIZSAN, Stefan BRAICA on . Posted in Volume VII, Nr. 4


Contrary to conventional beliefs, heart rate variability (HRV) is not strictly regular, reflecting the nonlinear control exerted primarily by the autonomous nervous system. The concept of sympathovagal balance has recently emerged to describe the dual and opposing effects of the sympathetic and parasympathetic influences on the activity of the sinus node. We investigated the sympathovagal influences on HRV during two complementary psychophysiological conditions, that is, controlled relaxation and anxiety, induced on subjects scorring low or high on the anxiety as trait scale. The beat-to-beat (R-R) intervals, the power in low- (LF) and high-frequency (HF) bands, and the LF/HF ratio were explored as indices of sympathovagal balance. Our results indicated a significant difference between the R-R intervals in relaxation vs anxiety, both for low- and high-anxiety subjects. We interpreted these results as evidence that the R-R interval discriminates between subjects with low and high anxiety as trait, and between opposing psychophysiological states like relaxation and anxiety. The analysis of the other HRV indicators (LF, HF, LF/HF)) supported the divergent effects of sympathovagal balance in relaxation and anxiety, although further work is needed in order to get the statistical power to establish whether these variables could reliably reflect differences in the autonomic modulation of HRV between subjects with low- and high anxiety as trait. We present here results supporting the differential autonomic modulation of HRV in low and high anxiety subjects, during controlled relaxation and anxiety. These results may challenge both a physiological, and a personological understanding.

KEYWORDS: heart rate variability, anxiety as trait, controlled relaxation, controlled anxiety