title: Heart-rate and blood-pressure variability during psychophysiological tasks involving speech: influence of respiration.
abstract: Changes in heart-rate and systolic arterial pressure variability (HRV and SAPV) indexes have been used in psychophysiology to assess autonomic activation, including during tasks involving speech. The current article clearly demonstrates in a sample of 25 adult subjects that the erratic and broadband respiratory patterns during such tasks violate the usual assumption that respiration is limited to the high-frequency band (0.15-0.4 Hz). For these tasks, interindividual differences and rest-task changes in HRV and SAPV in the low-frequency band (0.04-0.15 Hz) can be explained, to a large extent, by variations in the respiratory volume signal. This makes the use of HRV and SAPV as markers of autonomic function during these tasks highly questionable. Furthermore, a number of subjects with long respiratory period at rest were identified, whose presence in the sample can bias the estimation of baseline rest values.
authors.affiliation: Biomedical Engineering Programme (COPPE), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Beda
authors.forename: Frederico C
authors.initials: FC
authors.lastname: Jandre
authors.forename: David I W
authors.initials: DI
authors.lastname: Phillips
authors.forename: Antonio
authors.initials: A
authors.lastname: Giannella-Neto
authors.forename: David M
authors.initials: DM
authors.lastname: Simpson
mesh_terms: D000328:Adult; D001794:Blood Pressure / Q000502:physiology*; D015331:Cohort Studies; D003627:Data Interpretation, Statistical; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D015656:Respiratory Mechanics / Q000502:physiology*; D012146:Rest / Q000502:physiology; D013060:Speech / Q000502:physiology*