Autonomic correlates of individual differences in human intellectual activity

The individual differences in the autonomic support of intellectual activity, including simple and complex sensorimotor reactions, memorization and reproduction (on the screen of the monitor) of visual information, were studied. The rate of performing intellectual computer-aided tests is a relatively steady individual characteristic revealed in different kinds of activity. Students who reached a high speed and accurately performed intellectual visuomotor tasks were characterized by a high lability of autonomic indices, which manifests itself in a change in the absolute values and relationship of heart and respiration rates in accordance with activity stages. These changes were specific for each form of activity and were connected with the results of the tests. Under the initial conditions, these students were characterized by high values of TP and the power of the LF and HF ranges of heart rate variability at a LF/HF ratio close to unity.     

Efficiency of biofeedback training of functional state regulation depending on individual psychophysiological characteristics

The psychophysiological characteristics of the subjects (emotional stability, autonomic lability, tension of autonomic regulation of cardiac activity, and EEG characteristics) were estimated. The efficiency of relaxation regulation training with the use of biofeedback (with the electrocutaneous impedance as a BF signal) was studied. Before and after BF training, an electrophysiological experiment was carried out, namely, a “relaxation test” without BF support. The test consisted of three situations: background, relaxation, and the state after coming out of relaxation. During the test, EEGs of different cortical areas (α bands) and autonomic indices were recorded. A short-term memory test was carried out with the purpose of controlling changes in the functional status. It has been shown that even a short training cycle of five sessions in most cases provided relaxation and improvement in self-regulation, accompanied by improvement of the mnestic activity. The effect of individual psychophysiological characteristics on the success of BF training has been established. A high autonomic lability, a high level of nonspecific cortex activity, as well as a dysfunction of the frontal-thalamic system, should be regarded as factors preventing effective self-regulation training.     

Lateral Preferences as Possible Phenotypic Predictors of the Reserves of the Cardiovascular System and the Features of Sensorimotor Integration in Climbers

The lateral preferences of the hands, the reserves of the cardiovascular system and the features of sensorimotor integration in mountain climbers as possible predictors of adaptation to extreme factors of the external environment have been investigated. The subjects were 15 climbers of high class (men aged 25.5–62.8 years). We used the following methods: reflexometric technique ReBFB (complex sensorimotor reaction in the model of go/no-go, computer simulation according to Chernikov); the assessment of lateral preferences using the standard samples; the orthostatic test (with the recording of the heart rate and evaluation of adaptive reserves based on the indices of mathematical analysis of the cardiac rhythm in the transition period according to a technique by Riftin). Sensorimotor integration was performed under normal conditions and under normobaric hypoxia. All indicators were correlated with the age and proficiency of the climbers. We observed no statistically significant correlations between age and the reserves of the cardiovascular system in the group of climbers. Reflexometry in normoxic conditions showed an improvement in the orientation of subjects in the sensory flow as compared with the initial level. The sensorimotor integration (as a response of sensorimotor responses) was more stable during hypoxia as compared with the same indices in normoxia. Noticeable correlation was observed between the results of the humeral test and the reserves of the cardiovascular system defined by orthostatic hypotension: the reserves were higher in the subjects with a higher level of left-hand preference. The regulation of the autonomic nervous system is correlated with left-handedness, which results in more effective adaptation to the high altitude in left-handers. The parameter of handedness can be used as a phenotypic predictor of the level of the cardiovascular system reserves in climbers. It is suggested that the factor of hypoxia with small exposure has a stimulating effect on sensorimotor integration in climbers.     

The daily pattern of heart rate, body temperature, locomotor activity, and autonomic nervous activity in congenitally bronchial-hypersensitive (BHS) and bronchial-hyposensitive (BHR) guinea pigs.

We studied the characteristics of the rhythmicity of heart rate (HR), body temperature (BT), locomotor activity (LA) and autonomic nervous activity in bronchial-hypersensitive (BHS) and bronchial-hyposensitive (BHR) guinea pigs. For this purpose, HR, BT, LA, and electrocardiogram (ECG) were recorded from conscious and unrestrained guinea pigs using a telemetry system. Autonomic nervous activity was analyzed by power spectral analysis of heart rate variability. Nocturnal patterns, in which the values in the dark phase (20:00-06:00) were higher than those in the light phase (06:00-20:00), were observed in HR, BT and LA in both strains of guinea pigs. The autonomic nervous activity in BHS guinea pigs showed a daily pattern, although BHR guinea pigs did not show such a rhythmicity. The high frequency (HF) power in BHS guinea pigs was higher than that in BHR guinea pigs throughout the day. Moreover, the low frequency/high frequency (LF/HF) ratio in BHS guinea pigs was lower than that in BHR guinea pigs throughout the day. These results suggest that parasympathetic nervous activity may be predominant in BHS guinea pigs.     

Cardiac Autonomic Activity During Human Sleep: Analysis of Sleep Stages and Sleep Cycles

In this study characteristics of cardiac functioning were investigated in nine subjects during their nocturnal sleep. The pre-ejection period and the high frequency component of heart rate variability were used as indices of cardiac sympathetic and parasympathetic activity of the autonomic nervous system respectively. Heart rate and the autonomic indices were assessed across physiological determined sleep stages and consecutive temporal sleep cycles. Repeated measures ANOVA analyses indicated a significant pattern of heart rate as a function of sleep stages, which was mirrored by parasympathetic activity. Further, a significant decrease of heart rate as a function of sleep cycles was mirrored by an increase of sympathetic activity. Moreover, non-REM/REM differences revealed a dominant role of parasympathetic activity during sleep stages as well as sleep cycles. These findings demonstrate that sympathetic activity is influenced by time asleep, whereas parasympathetic activity is influenced by the depth of sleep.     

Cardiac Autonomic Activity During Human Sleep: Analysis of Sleep Stages and Sleep Cycles

In this study characteristics of cardiac functioning were investigated in nine subjects during their nocturnal sleep. The pre-ejection period and the high frequency component of heart rate variability were used as indices of cardiac sympathetic and parasympathetic activity of the autonomic nervous system respectively. Heart rate and the autonomic indices were assessed across physiological determined sleep stages and consecutive temporal sleep cycles. Repeated measures ANOVA analyses indicated a significant pattern of heart rate as a function of sleep stages, which was mirrored by parasympathetic activity. Further, a significant decrease of heart rate as a function of sleep cycles was mirrored by an increase of sympathetic activity. Moreover, non-REM/REM differences revealed a dominant role of parasympathetic activity during sleep stages as well as sleep cycles. These findings demonstrate that sympathetic activity is influenced by time asleep, whereas parasympathetic activity is influenced by the depth of sleep.     

Reaction of Cardiac Activity of Senior Pupils of Schools Providing Differentiated Education upon Examination Stress

Effects of examination stress on psychological characteristics and indices of the autonomic nervous system were studied in pupils of the eighth and tenth grades of high schools providing differential (test group, Neuron gymnasium) and general education (control group). General health state and levels of activity and mood (feeling, activity, mood; FAM) and neuroticism (according to Eysenck) were determined in both groups. Main hemodynamic indices (heart rate and blood pressure) were measured, and mathematical analysis of the heart rate by was performed according to Baevskii. Comparative analysis of psychophysiological tests and heart rate changes in the control and test groups points to a high tension in the cardiac rhythm regulation mechanisms and strong anxiety in schoolchildren in the differential education school. The character and depth of preexamination stress depended on the type of autonomic control of cardiac activity. Schoolchildren with sympathicotonic cardiac rhythm regulation showed the strongest emotional tension. Schoolchildren with the normotonic type of regulation were the most calm.     

Power spectral analysis of heart rate variability for assessment of diurnal variation of autonomic nervous activity in guinea pigs.

We established characteristics of power spectral analysis of heart rate variability, and assessed the diurnal variations of autonomic nervous function in guinea pigs. For this purpose, an electrocardiogram (ECG) was recorded for 24 hr from conscious and unrestrained guinea pigs using a telemetry system. There were two major spectral components, at low frequency (LF) and high frequency (HF) bands, in the power spectrum of HR variability. On the basis of these data, we defined two frequency bands of interest: LF (0.07-0.7 Hz) and HF (0.7-3.0 Hz). The power of LF was higher than that of HF in the normal guinea pigs. Atropine significantly reduced power at HF. Propranolol also significantly reduced power at LF. Furthermore, the decrease in the parasympathetic mechanism produced by atropine was reflected in a slight increase in the LF/HF ratio. The LF/HF ratio appeared to follow the reductions of sympathetic activity produced by propranolol. Autonomic blockade studies indicated that the HF component reflected parasympathetic activity and the LF/HF ratio seemed to be a convenient index of autonomic balance. Nocturnal patterns, in which the values of heart rate in the dark phase (20:00-06:00) were higher than those in the light phase (06:00-20:00), were observed. However, the HF, LF and the LF/HF ratio showed no daily pattern. These results suggest that the autonomic nervous function in guinea pigs has no clear circadian rhythmicity. Therefore, this information may be useful for future studies concerning the autonomic nervous function in this species.     

Effects of spatial-imagery task performance on the heart rate variability

Effects of the efficiency of spatial task performance on the autonomic heart control were studied. Dynamic changes in autonomic balance diagnosed on the heart rate variability during maze-model task performance (the type of spatial-imagery activity) showed that the type of heart rate regulation depended on the performance efficiency. The results suggest that in subjects with low performance efficiency, problems in performance are associated with negative emotions that produce the emotional psychogenic stress. In subjects with high efficiency, the autonomic contour of the heart rate regulation prevailed. This was presumable associated with the adequacy of the maze-model task.     

Circadian rhythms of physiological functions in men and women as related to shift work

Operators of both sexes employed in the pulp industry were examined during a triple-shift cycle of shift work. Changes in the body temperature, heart rate, blood pressure, and sensorimotor coordination parameters were used as indicators of the circadian rhythms of their physiological functions. Sex-related differences were found with respect to a number of parameters (the muscular strength, critical flicker frequency, duration of the performance of a coordination test and coordination index, blood pressure and autonomic index, and physical general condition and mood scores). Fatigue in this type of operator activity was efficiently detected by the general condition, activity, mood (WAM) test score (especially in women), the number of errors in the test for sensorimotor coordination, and the coordination index.     

Evaluation of the functional state of operators with allowance for individual psychological characteristics

This article deals with the features of the evaluation of changes in the functional state during the professional activity of operators. We estimated the dynamics of the functional state and efficiency of operators under the effect of aircraft noise and individual psychophysiological characteristics. We also investigated changes in the functional state of operators depending on their psychological characteristics. It was found that changes in the functional state of the organism in operators with high levels of anxiety, low degrees of extraversion, and high emotional lability were more pronounced in the modeling of operator activity with exposure to aircraft noise, as evidenced by significant changes in psychophysiological parameters. After 60 minutes of noise stress, the latent period of a simple and a complex sensorimotor reaction in introverts increased by 9.1% (p < 0.05) and 8.1% (p < 0.05), respectively. In the group of subjects with high levels of anxiety, there was a decrease in the general state, activity, and mood by 18.9% (p < 0.01), 20.9%, and 14.9% (p < 0.05), respectively, and a decrease in the accuracy of reaction to a moving object by three times (p < 0.05). The latent period of simple sensorimotor reaction in emotionally labile subjects after the exercise was increased by 15% (p < 0.05), and the reaction time on a moving object was increased by 8.9% (p < 0.05) as compared with the group of emotionally stable subjects. Thus, the data suggest that changes in the functional state of operators depends on the level of extraversion, personal anxiety, and emotional lability, and does not depend on the level of behavioral regulation, which must be taken into consideration during the assessment of functional state.     

Assessment of spectral analysis of heart rate variability in patients with history of atrial fibrillation by means of age-dependent parameters

Heart rate variability evaluation is a useful diagnostic tool for autonomic nervous balance assessment. The role of the autonomic nervous system in aetiology of atrial fibrillation is sometimes clear as a trigger from a patient's history, but mostly it acts as a modulating factor which is not easy to detect. The present study demonstrates results of spectral analysis of short-term heart rate variability during ortho-clinostatic tests processed by means of age-dependent parameters. An original telemetric system and a unique method for heart rate variability assessment, developed by the Faculty of Physical Culture, were applied for the first time to examine patients with the history of atrial fibrillation.     

Effects of psychological stress on autonomic control of heart in rats.

The aim of this study was to examine the effects of psychological stress on autonomic control of the heart in rats. For this purpose, we evoked anxiety-like or fear-like states in rats by means of classical conditioning and examined changes in autonomic nervous activity using an implanted telemetry system and power spectral analysis of heart rate variability. Anxiety-like states resulted in a significant increase in heart rate (HR), low frequency (LF) power, and LF/HF ratio, with no change in high frequency (HF) power. Fear-like states resulted in a significant increase in HR and a significant decrease in HF power with no significant change in both LF power and LF/HF ratio, although LF/HF ratio increased slightly. These results suggest that autonomic balance becomes predominant in sympathetic nervous activity in both anxiety-like and fear-like states. These changes in rats correspond to changes which are relevant to cardiovascular diseases in humans under many kinds of psychological stress. Therefore, the experimental design of this study is a useful experimental model for investigating the effects of psychological stress on autonomic control of the heart in humans.     

The influence of examination stress on psychophysiological characteristics and heart rate in students

With the aim to assess the influence of pre-examination psychoemotional stress on the level of centralization of the heart rate control, mathematical analysis of ECG of students was performed in normal condition (a common day of academic semester), before, and after an examination. The ECG was recorded and processed with the help of IBM-486 PC. R-R cardiointevalograms were processed by the method of variational pulsometry after Baevsky. Common quantitative heart rate indices were studied. The level of anxiety of students was assessed by Spilberger, and subjective estimations of general condition, activity and mood were obtained from the respective questionnaire. Three types of heart rate reactions on the examination stress were revealed. The reactions depended on the individual typological characteristics and the state of autonomic nervous system.     

Twenty-four hour monitoring of heart rate and activity in patients with diabetes mellitus: a comparison with clinic investigations.

Heart rate and activity were recorded continuously in 11 selected diabetics during a normal day, and the observations were compared with results obtained in the same patients in the diabetic outpatient clinic 10 months earlier. Both sets of findings agreed well in heart rate variability and postural tachycardia. In patients with well-controlled diabetes simple tests of reflex cardiovascular control produce results that may be useful in following the course of diabetic autonomic neuropathy.     

Noninvasive cardiac psychophysiology as a tool for translational science with marmosets

The importance of marmosets for comparative and translational science has grown in recent years because of their relatively rapid development, birth cohorts of twins, family social structure, and genetic tractability. Despite this, they remain understudied in investigations of affective processes. In this methodological note, we establish the validity of using noninvasive commercially available equipment to record cardiac physiology and compute indices of autonomic nervous system activity—a major component of affective processes. Specifically, we recorded electrocardiogram and impedance cardiogram, from which we derived heart rate, respiration rate, measures of high‐frequency heart rate variability (indices of parasympathetic autonomic nervous system activity), and ventricular contractility (an index of sympathetic autonomic nervous system activity). Our methods produced physiologically plausible data, and further, animals with increased heart rates during testing were also more reactive to isolation from their social partner and presentation of novel objects, though no relationship was observed between reactivity and specific indices of parasympathetic or sympathetic nervous system activity.     

Autonomic Activity Assessed by Heart Rate Spectral Analysis Varies with Fat Distribution in Obese Women

Obesity in humans has been associated with altered autonomic nervous system activity. The objective of this study was to examine the relationship between autonomic function and body fat distribution in 16 obese, postmenopausal women using power spectrum analysis of heart rate variability. Using this technique, a low frequency peak (0.04-0.12 Hz) reflecting mixed sympathetic and parasympathetic activity, and a high frequency peak (0.22-0.28 Hz) reflecting parasympathetic activity, were identified from 5-minute consecutive heart rate data (both supine and standing). Autonomic activity in upper body (UBO) vs. lower body obesity (LBO)(by waist-to-hip ratio) and subcutaneous vs. visceral obesity (by CT scan) was evaluated. Power spectrum data were log transformed to normalize the data. The results showed that standing, low-frequency power (reflecting sympathetic activity) and supine, high-frequency power (reflecting parasympathetic activity) were significantly greater in UBO than in LBO, and in visceral compared to subcutaneous obesity. Women with combined UBO and visceral obesity had significantly higher cardiac sympathetic and parasympathetic activity than any other subgroup. We conclude that cardiac autonomic function as assessed by heart rate spectral analysis varies in women depending on their regional body fat distribution.     

Music Attenuated a Decrease in Parasympathetic Nervous System Activity after Exercise

Music and exercise can both affect autonomic nervous system activity. However, the effects of the combination of music and exercise on autonomic activity are poorly understood. Additionally, it remains unknown whether music affects post-exercise orthostatic tolerance. The aim of this study was to evaluate the effects of music on autonomic nervous system activity in orthostatic tolerance after exercise. Twenty-six healthy graduate students participated in four sessions in a random order on four separate days: a sedentary session, a music session, a bicycling session, and a bicycling with music session. Participants were asked to listen to their favorite music and to exercise on a cycle ergometer. We evaluated autonomic nervous system activity before and after each session using frequency analysis of heart rate variability. High frequency power, an index of parasympathetic nervous system activity, was significantly increased in the music session. Heart rate was increased, and high frequency power was decreased, in the bicycling session. There was no significant difference in high frequency power before and after the bicycling with music session, although heart rate was significantly increased. Additionally, both music and exercise did not significantly affect heart rate, systolic blood pressure or also heart rate variability indices in the orthostatic test. These data suggest that music increased parasympathetic activity and attenuated the exercise-induced decrease in parasympathetic activity without altering the orthostatic tolerance after exercise. Therefore, music may be an effective approach for improving post-exercise parasympathetic reactivation, resulting in a faster recovery and a reduction in cardiac stress after exercise.     

Evidence of dominant parasympathetic nervous activity of great cormorants (<Emphasis Type="Italic">Phalacrocorax carbo</Emphasis>)

The characteristics of autonomic nervous activity were examined on captive great cormorants Phalacrocorax carbo hanedae, using a power spectral analysis of heart rate variability. Heart rates were calculated from recordings of the electrocardiograms of the birds via embarked data loggers. We investigated the effects of blockades of the sympathetic or parasympathetic nervous systems using the indices of autonomic nervous activity such as high frequency (0.061–1.5 Hz) component, low frequency (0.02–0.060 Hz) component and the low frequency power component to high frequency power component ratio. Resting heart rate (85.5 ± 6.1 bpm) was lower than the intrinsic heart rate (259.2 ± 15.3 bpm). The heart rate drastically increased after the injection of the parasympathetic nervous blocker, on the other hand it slightly decreased after the injection of the sympathetic nervous blocker. The sympathetic, parasympathetic and net autonomic nervous tones calculated from heart rate with and without blockades were 40.9 ± 27.6, −44.5 ± 7.4 and −29.5 ± 9.0%, respectively. The effect of the parasympathetic nervous blockade on low frequency and high frequency power was greater than that of the sympathetic nervous blockade. Those data suggested that the parasympathetic nervous activity was dominant for great cormorants.     

Features of the psychophysiological status of men with different levels of vestibular-autonomic resistance and their interrelation with etiology and pathogenesis of motion sickness

The results of more than 600 surveys of 200 healthy male volunteers aged 23–45 years, including parameters of electroencephalograms, sensorimotor reactions, and questionnaires of Cattell, Strelau and Taylor, have been analyzed. Division into groups with a high, moderate, and low vestibular-autonomic resistance (VAR) has been made on the basis of tolerance to the rotary test with interrupted cumulation of Coriolis accelerations. It has been shown that the VAR level, along with differences in sensitivity between the peripheral part of the vestibular analyzer and other sensory systems, is highly determined by the differences in strength, lability, activation, and dynamism of the nervous system, as well as the balance and mobility of the processes of excitation/inhibition. The VAR level is also determined by differences in the psychophysiological status, characterizing a state of psychomotor reactions, features of personality and temperament, and cognitive abilities, while the intensity of vestibular-autonomic disorders in men susceptible to motion sickness is enhanced by the influence of their psychoemotional condition during vestibular stimulation—the subjective sensation of being “lost in space”, manifestation of mental discomfort and anxiety, accompanied by autonomic and neurohormonal reactions, whose extreme form can be characterized as “the threatened state syndrome.”