[EEG spectral characteristics during heart rate variability biofeedback in healthy people]. / Izmenenie spektral'nykh kharakteristik élektroéntsefalogrammy v protsesse bioupravleniia parametrami variabel'nosti serdechnogo ritma u zdorovykh.

AIM: To evaluate changes in electroencephalogram (EEG) spectral characteristics during a single session of heart rate variability biofeedback (HRV BF). MATERIAL AND METHODS: One hundred and fifty adolescents, aged 16-17 years, were studied. Adolescents of the BF-group (n=110) conducted HRV BF session to enhance vagal influences on the heart rhythm. Adolescents of the control group (n=40) remained in relaxed resting state. EEG was recorded with eyes closed before and after BF training. EEG absolute spectral power values of parts without artifacts in each frequency band were determined. RESULTS AND CONCLUSION: The ability of the volunteer to change the heart rhythm activity determines the extent of its impact on the functions of central autonomic structures. This method of BF training helps to improve the cortical stability: an increase in alpha- and decrease in theta EEG-activity. The synchronization process of brain activity in the dynamics of BF training is most clearly manifested in the right brain hemisphere, with the frequent involvement of prefrontal brain areas.

[Individual Types Reactivity of EEG Oscillations in Effective Heart Rhythm Biofeedback Parameters in Adolescents and Young People in the North].

A single session of heart rate variability (HRV) biofeedback in apparently healthy young people and adolescents aged 14-17 years in order to increase vagal effects on heart rhythm and also electroencephalograms were carried out. Different variants of EEG spectral power during the successful HRV biofeedback session were identified. In the case of I variant of EEG activity the increase of power spectrum of alpha-, betal-, theta-components takes place in all parts of the brain. In the case of II variant of EEG activity the reduction of power spectrum of alpha-, betal-, theta-activity in all parts of the brain was observed. I and II variants of EEG activity cause more intensive regime of cortical-subcortical interactions. During the III variant of EEG activity the successful biofeedback is accompanied by increase of alpha activity in the central, front and anteriofrontal brain parts and so indicates the formation of thalamocortical relations of neural network in order to optimize the vegetal regulation of heart function. There was an increase in alpha- and beta1-activity in the parietal, central, frontal and temporal brain parts during the IV variant of EEG activity and so that it provides the relief of neural networks communication for information processing. As a result of V variance of EEG activity there was the increase of power spectrum of theta activity in the central and frontal parts of both cerebral hemispheres, so it was associated with the cortical-hippocampal interactions to achieve a successful biofeedback.

[Comparison of electroencephalogram changes at cardiovascular training in adolescents of subpolar and polar northern territories].

The features of the electroencephalogram (EEG) at the heart rate variability single biofeedback session in adolescents aged 15-17 years living in the subpolar and polar northern regions were determined. In adolescents of the subpolar region identified shaped age EEG pattern. We have established higher diencephalic and subcortical brain structures activity manifested in the elevated theta-activity levels and the diffuse photic driving reactions in adolescents of the polar region than in adolescents of subpolar region. In the dynamics of the biofeedback sessions in both regions there were identified groups of persons with both increased alpha-activity spectral power and decreased of it. After biofeedback sessions in adolescents of polar region more prolonged increase of alpha-activity, more pronounced reduction of theta-activity and the photic driving reactions were revealed. Changes in EEG patterns are most characteristic of the right brain hemisphere involving the frontal brain areas.

[The success of heart rate variability biofeedback parameters in persons with different levels of blood pressure].

OBJECTIVE: The aim was to determine the nature of cardiovascular reactions during a single session of heart rate variability (HRV) biofeedback in order to increase vagal effects on heart rhythm in patients with different initial levels of blood pressure (BP). PARTICIPANTS AND METHODS: 33 people with normal blood pressure (group I), 20 people with uncorrected arterial hypertension (AH) grade 1-2 (group II) and 22 people with AH grade 1-2 taking antihypertensive drugs (group III) were observed. The parameters of heart rate variability (HRV), BP and pulse aximetry in the initial stage, during a single HRV biofeedback session and after this session in order to increase the total power of the HRV spectrum (each stage 5 min). RESULTS: In patients of group II low success of HRV biofeedback session, a high sympathetic reactivity and reduced oxygen blood saturation were determined. A reactivity of vagal mechanism is more pronounced in persons of group III than in those of group II. It is reflected in a significant increase in their total power of the HRV spectrum compared to the initial values and in uptrend saturation levels during the biofeedback session. CONCLUSION: The ability to HRV biofeedback in order to increase the total power of the HRV spectrum for standard short recording (5 min) can be seen as a test to determine the safety reserves of vagal autonomic cardiovascular regulation in persons with increased blood pressure.

[The assessment of reactions of polygraphic parameters at HRV-biofeedback training in adolescents with different variants of cardiac autonomic nervous system tone].

There is examine a character of change of brain bioelectric activity and polygraphic indicators at sessions of biofeedback by heart rhythm variability parameters (HRV-biofeedback) in 15-17 years adolescents who have different variants of cardiac autonomic nervous system tone. It is taped, that adolescents with cardiac balanced tone have more intensive optimization of functional brain activity in comparison with adolescents who have cardiac sympathetic tone - increase on alpha-activity and theta-activity depression in electroencephalogram structure. There were optimization of neurodynamic processes and most expressed stabilization of the hemodynamics indicators in adolescents with cardiac sympathetic tone after HRV-biofeedback training.

[Thyroid effect on brain activity in adolescents during heart rhythm biofeedback session].

Types of neurophysiologic and thyroid condition in 15-17-year old adolescents were studied for the purpose of heart rhythm biofeedback session effect by heart rhythm variability parameters. Changes of heart rhythm vegetative regulation activity modulate functional capacities of central vegetative regulation structures. The biofeedback training with heart rhythm variability parameters increases brain bioelectrical activity in different frequency ranges. The thyroid system modulates functional activity of vegetative regulation central structures uppermost at sympathotonic and thyreotropin increasing leads to increase of rhythm maker structure reactivity in brain.