Effects of controlled breathing, mental activity and mental stress with or without verbalization on heart rate variability

Luciano Bernardi, Joanna Wdowczyk-Szulc, Cinzia Valenti, Stefano Castoldi, Claudio Passino, Giammario Spadacini, Peter Sleight

Research output: Contribution to journalArticle


Objectives. To assess whether talking or reading (silently or aloud) could affect heart rate variability (HRV) and to what extent these changes require a simultaneous recording of respiratory activity to be correctly interpreted. Background. Sympathetic predominance in the power spectrum obtained from short- and long-term HRV recordings predicts a poor prognosis in a number of cardiac diseases. Heart rate variability is often recorded without measuring respiration; slow breaths might artefactually increase low frequency power in RR interval (RR) and falsely mimic sympathetic activation. Methods. In 12 healthy volunteers we evaluated the effect of free talking and reading, silently and aloud, on respiration, RR and blood pressure (BP). We also compared spontaneous breathing to controlled breathing and mental arithmetic, silent or aloud. The power in the so called low-(LF) and high-frequency (HF) bands in RR and BP was obtained from autoregressive power spectrum analysis. Results. Compared with spontaneous breathing, reading silently increased the speed of breathing (p <0.05), decreased mean RR and RR variability and increased BP. Reading aloud, free talking and mental arithmetic aloud shifted the respiratory frequency into the LF band, thus increasing LF% and decreasing HF% to a similar degree in both RR and respiration, with decrease in mean RR but with minor differences in crude RR variability. Conclusions. Simple mental and verbal activities markedly affect HRV through changes in respiratory frequency. This possibility should be taken into account when analyzing HRV without simultaneous acquisition and analysis of respiration. (C) 2000 by the American College of Cardiology.

Original languageEnglish
Pages (from-to)1462-1469
Number of pages8
JournalJournal of the American College of Cardiology
Issue number6
Publication statusPublished - May 2000

ASJC Scopus subject areas

  • Nursing(all)

Fingerprint Dive into the research topics of 'Effects of controlled breathing, mental activity and mental stress with or without verbalization on heart rate variability'. Together they form a unique fingerprint.

  • Cite this