INDEXES OF HEART-RATE DEPEND ON TRAIT-ANX IETY

In 90 subjects (25 males and 65 females) aged 17-19 heart and respirat ion rates were telemetrically recorded with a <<Sport>> polygraph unde r conditions of rest and arithmetical load (periods of 3 min each). Sp ectral analysis of heart rate and respiration and statistical processi ng was performed off-line by an IBM PC XT with the software package PF E2. Anxiety was tested according to Spilberger State-Trait-Anxiety Inv entory with Hanin modification and strength of excitation and inhibiti on according to Strelau Temperament Inventory. It was shown that the g roup characterized by the high trait-anxiety had significantly higher resting heart rate and Bayevsky index of strain than the group with lo w trait-anxiety. The groups differed also in R - R interval variabilit y (standard deviation) under arithmetical load. In the group with high trait-anxiety R - R interval variability was lower than in the other group mainly in two frequency bands of R - R power spectrum, i. e., th ose of respiratory arhythmia (RA) and Traube-Hering-Mayer waves (THM). Mental load evoked an increase in the heart rate and Bayevsky index a nd decrease in the power of RA and THM frequency bands. Such peculiari ties of the heart rate in both groups during the periods of rest and i nformational load can be explaned in the framework of reciprocal relat ionship between orienting (lower trait-anxiety, lower heart rate, high er R - R interval variability mainly in RA and THM bands of R - R powe r spectrum) and defensive reflexes (higher trait-anxiety, higher heart rate, lower R - R interval variability, in particular in RA and THM b ands of R - R power spectrum).