[THE INFLUENCE OF INFORMATION LOAD ON THE TIMECOURSE OF SPECTRAL PARAMETERS OF HEART RATE VARIABILITY IN STUDENTS...

In the study, distinctions in daily timecourse of spectral parameters of the heart rate variability (HRV) at rest wakefulness and at information load in students with different chronotypes are revealed. The most pronounced changes in the general spectral power of HRV due to fluctuations of all parameters, but especially the VLF, LF, HF waves and the LF/HF index were found in students with a daily chronotype at rest and after implementation of load tests during the different periods of the school day. In persons with an evening chronotype in conditions of rest, the greatest variability was found in a spectral HF component of HRV, and responses to information load were found during the day in different combinations of changes of LF and HF components and the LF/HF index. In students with a morning chronotype during rest wakefulness, considerable fluctuations of a proportion of LF waves were observed, whereas in response to information load during certain periods of the day, representation of LF and HF components of the spectrum was changed. The wide variability of HRV spectral parameters in students with daily activity, compared to students with early and late activities, reflects the advantages of persons with a daily chronotype in terms of adaptation to different operation modes and irregular stress information in the course of the day.