Airways, respiration, and respiratory sinus arrhythmia during picture viewing

Emotional stimuli can cause airway constriction; however, it is uncertain whether a dimensional or categorical model of emotion can better describe airway changes. Also, little is known about the affective modulation of respiration and vagal activity, which can influence airway tone. We studied changes in oscillatory resistance (Ros), respiration, and respiratory sinus arrhythmia (RSA) in asthmatics and controls during viewing of affective pictures eliciting anxiety, depression, disgust, happiness, contentment, erotic tension, or neutral affect. Ros, respiration, cardiac activity, and self-report were measured during picture presentations. Ros increased monotonically with picture unpleasantness mainly due to disgust pictures. RSA and respiratory timing parameters were particularly sensitive to erotic pictures. Differences between asthmatics and controls were minimal, suggesting that airway responses to unpleasant pictures are not specific to asthma.     

Modulation of respiratory sinus arrhythmia by respiration rate and volume: stability across posture and volume variations

We tested the assumption that the slope of the within-individual regression equation of respiratory sinus arrhythmia (RSA) normalized by tidal volume (V(T)) upon respiratory cycle length (T(TOT)) can characterize ventilatory RSA modulation independent of cardiac vagal tone, whereas the intercept is varying as a function of vagal tone. We also explored whether a variation of V(T) is necessary to estimate slopes reliably. Four 3-min sequences paced at 8-18 cycles/min were performed supine and standing. Participants also breathed the same sequences in supine posture with voluntarily varying V(T). The mean slope of RSA/V(T) upon T(TOT) was identical, and the mean intercept was lower for standing than supine (spontaneous V(T)) conditions. Stability of slopes was low between body postures, and was higher between spontaneous V(T) versus varying V(T) at the same body posture. The regression of RSA/V(T) upon T(TOT) allows for a valid estimation of ventilatory influences on RSA.     

呼吸性窦性心律不齐定量分析研究进展

呼吸性窦性心律不齐(RSA)是一种心率随呼吸周期性波动的生理现象。近年来在临床上常被用作心迷走神经张力的非侵入式检测指征。但它的定量分析受呼吸参数、体位、体动等因素影响,使得至今还没有建立起一个通用的定量分析标准和校准方法。本文主要介绍了五种常见的定量分析方法:相邻R-R间期差值均方根(RMSSD)法、峰谷(pvRSA)法、逐次呼吸余弦拟合(cosinor fitting)法、谱分析(spectral analysis)法以及时频联合分析(JTFA)法;同时本文介绍了定量分析中常见的呼吸参数校准方法:引导呼吸法、协方差分析统计学控制法、相对呼吸参数残余量法以及潮气量修正法。最后,对如何解决现阶段RSA定量估计中存在的问题做了展望。     

引导呼吸下的呼吸性窦性心律不齐的研究

研究渐进性引导呼吸对呼吸性窦性心率不齐(RSA)的影响。对15名健康成年男性采集引导呼吸率依次为【14次/min—12.5次/min—11次/min—9.5次/min—8次/min—7次/min】状态下的同步心电、呼吸信号,采用提取RSA时、频特征参数的方法来研究渐变性呼吸率对RSA的影响。计算结果显示:表征RSA强度的三个特征参数总体上随着呼吸率的逐渐降低均呈现出增大的变化趋势。RSA代表着呼吸系统对心血管系统的反射调控,此实验结果表明,随着呼吸率的降低,呼吸系统对心血管系统的反射调控作用逐渐增加,提示可通过改变呼吸模式来改善心血管系统的功能。     

Respiratory control when measuring respiratory sinus arrhythmia during a talking task

The current study explored the effects of talking on respiratory sinus arrhythmia (RSA) during a semi-structured emotional interview (Adult Attachment Interview) using 76 female undergraduates. The effectiveness of 2 different methodological approaches (i.e. talking baseline or transfer function) was explored as respiratory control during talking tasks. RSA was collected during resting baseline, talking baseline, and interview conditions. Subjective reports of distress were higher in the interview than in the other 2 conditions. Mean RSA levels were significantly lower in the 2 talking tasks than in the resting baseline. After applying a transfer function for respiratory control, there were no significant differences between the 3 conditions. Moderator analyses yielded lower RSA values in the talking baseline and interview conditions for participants who reported greater distress during the interview. It was concluded that respiratory controls are likely necessary when using RSA in talking paradigms and that both approaches appeared to be adequate.     

Contribution of tonic vagal modulation of heart rate,central respiratory drive,respiratory depth,and respiratory frequency to respiratory sinus arrhythmia during mental stress and physical exercise

This study tested various sources of changes in respiratory sinus arrhythmia (RSA). Twenty-two healthy participants participated in three experimental conditions (mental stress, relaxation, and mild physical exercise) that each consisted of three breathing parts (normal breathing, breathing compressed room air, and breathing compressed 5% CO2-enriched air). Independent contributions to changes in RSA were found for changes in tonic vagal modulation of heart rate, central respiratory drive (i.e., PaCO2), respiratory depth, and respiratory frequency. The relative contributions to changes in RSA differed for mental stress and physical exercise. It is concluded that uncorrected RSA will suffice to index within-subject changes in tonic vagal modulation of heart rate in most situations. However, if the central respiratory drive is expected to change, RSA should ideally be corrected for changes in PaCO2, respiratory depth, and respiratory frequency.     

Changes of respiratory sinus arrhythmia during the menstrual cycle depend on average heart rate

To evaluate the complex time course of changes in respiratory sinus arrhythmia (RSA) during the menstrual cycle, daily beat-to-beat morning recordings of heart rate (HR) were carried out in 26 healthy female subjects (age 20–29 years) during two menstrual cycles. For determination of fast, vagally mediated variations of HR we used a robust time-domain measure of RSA (logRSA). We found pronounced changes in HR during the menstrual cycle with a minimum in the early follicular phase and a maximum in the late luteal phase. There were large differences between individuals in the fluctuations of logRSA during the menstrual cycle that were related to average HR: subjects with a low HR exhibited higher values of logRSA in the luteal compared to the follicular phase, whereas the trend was reversed in subjects with a high HR. The difference of extreme points of logRSA fluctuations (early follicular and mid luteal phase) was correlated to average HR (r=–0.64, P<0.001). We conclude that different patterns of RSA fluctuations occur depending on the level of average HR. Electronic Publication     

Respiratory sinus arrhythmia, cardiac vagal tone, and respiration: Within- and between-individual relations

Respiratory sinus arrhythmia (RSA) is frequently employed as an intra- and interindividual index of cardiac parasympathetic tone, although the relationship of RSA to interindividual differences in cardiac vagal tone remains questionable. Our study examined between- and within-subject relations among RSA, cardiac vagal tone, and respiratory parameters. Twenty-nine young adults performed two sessions of tasks under no medication and single and double autonomic blockade (intravenously administered propranolol and atropine). Parasympathetic tone was determined from heart period responses to complete vagal blockade. Results indicated the following. Resting RSA does not accurately predict individual differences in cardiac vagal tone. However, RSA and heart period together do predict such individual differences reasonably well. The relationship between individual variations in RSA and vagal tone is not improved by controlling respiratory parameters. Substantial cardiac vagal activity occurs during inspiration, and intraindividual variations in respiratory measures confound the association between RSA and cardiac vagal tone.     

Interactive effects of social adversity and respiratory sinus arrhythmia activity on reactive and proactive aggression

Abnormal parasympathetic nervous system (PNS)‐related cardiac activity has been linked to aggression. However, little is known about how it interacts with psychosocial adversity in predisposing to reactive‐proactive aggression. In the current study, 84 male and female college students self‐reported reactive and proactive aggression, and were assessed for respiratory sinus arrhythmia (RSA), a measure of PNS‐related cardiac activity, during rest and when they contemplated an emotion‐evoking decision‐making task. Regression analyses showed that (a) resting RSA was positively linked to reactive aggression in conditions of high social adversity, and (b) RSA reactivity was positively associated with reactive but negatively associated with proactive aggression, in conditions of low social adversity. Main effects were not found for psychophysiological functioning or psychosocial adversity, suggesting the importance of their interaction. Findings support a biosocial basis for aggression and add additional support for the distinctions between reactive and proactive aggression.     

Heart rate and sustained attention during childhood: Age changes in anticipatory heart rate, primary bradycardia, and respiratory sinus arrhythmia

This study examined age changes in three aspects of heart rate responsivity elicited in an auditory oddball task; anticipatory heart rate change, primary bradycardia, and respiratory sinus arrhythmia. Three age groups (5-, 7-, and 9-year-old boys) were presented with series of target (15%) and standard (85%) tones. The results were consistent with the findings reported previously in the adult literature. Heart rate decreased in anticipation of the target tone. The morphology of anticipatory deceleration was somewhat different for the 5-year-olds compared to the older children. Stimuli presented during the early part of the cardiac cycle induced added deceleration, but this primary bradycardia did not differ between age groups. Respiratory sinus arrhythmia did not discriminate between age groups but was suppressed during the performance of the oddball task relative to base level. It was concluded that these three aspects of heart rate responsivity show developmental constancy rather than change.     

A genetic analysis of ambulatory cardiorespiratory coupling

This study assessed the heritability of ambulatory heart period, respiratory sinus arrhythmia (RSA), and respiration rate and tested the hypothesis that the well-established correlation between these variables is determined by common genetic factors. In 780 healthy twins and siblings, 24-h ambulatory recordings of ECG and thorax impedance were made. Genetic analyses showed considerable heritability for heart period (37%-48%), RSA (40%-55%), and respiration rate (27%-81%) at all daily periods. Significant genetic correlations were found throughout. Common genes explained large portions of the covariance between heart period and RSA and between respiration rate and RSA. During the afternoon and night, the covariance between respiration rate and RSA was completely determined by common genes. This overlap in genes can be exploited to increase the power of linkage studies to detect genetic variation influencing cardiovascular disease risk.     

Association between respiratory sinus arrhythmia and reductions in startle responding in three independent samples

Evidence suggests that respiratory sinus arrhythmia (RSA) may be an important indicator of physiological flexibility. However, few studies have examined the relation between RSA and defensive habituation, a process contingent on physiological flexibility. In three independent samples, habituation was defined as the time course of 9 startle responses. In Sample one and two, startle was recorded (1) while shock electrodes were attached to participants’ and (2) before a threat-of-shock task. In Sample three, startle was recorded without these two components. In the first two samples, startle magnitude significantly decreased over time but in Sample three, startle only decreased at a trend level. Further, low RSA was associated with less of a reduction in startle magnitude over time within the first two samples, but was unrelated to startle reduction in the third. This suggests that low RSA is associated with less habituation to contextual anxiety, which may reflect difficulties regulating anxiety.     

Baseline respiratory sinus arrhythmia and heart rate responses during sustained visual attention in preterm infants from 3 to 6 months of age

Three groups of preterm infants were studied longitudinally at 14, 20, and 26 weeks of age (corrected for gestational age). The groups included infants with no perinatal medical complications, those with mild respiratory problems requiring ventilatory assistance, and those with respiratory distress syndrome. Baseline heart rate and respiratory sinus arrhythmia (RSA) were recorded for 5 min, and heart rate was also recorded while the infants engaged in sustained visual attention to stimuli presented on video monitors. The heart rate response during stimulus orienting and sustained attention was smaller in those infants with respiratory distress syndrome than in the other preterm infants and in comparison with the response seen in full-term infants in previous research. Magnitude of RSA was positively correlated with the attention responses irrespective of the preterm group assignment. There was greater stability in baseline heart rate and RSA for the preterm infants than has been found with full-term infants. These data suggest that the cardiorespiratory functioning of the preterm infant indexes a stable individual difference characteristic that is correlated with heart responses during sustained attention, and heart rate attention systems may be damaged in the high-risk preterm infant.     

Individual differences in the autonomic origins of heart rate reactivity: the psychometrics of respiratory sinus arrhythmia and preejection period

Heart rate reactivity has been conceptualized, at least implicitly, as a unidimensional construct ranging from low to high, reflecting individual differences in adrenergic reactivity to daily stressors. However, an individual's classification as high in heart rate reactivity ignores possible individual differences in the autonomic origins of this reactivity. Sixty-eight women were exposed to orthostatic and speech stressors to determine the psychometric properties (postural stability, convergent and discriminant validity) of heart rate, preejection period, and respiratory sinus arrhythmia. Results revealed that (a) basal, stress, simple reactivity (stress - baseline), and residualized change indices of heart rate, preejection period, and respiratory sinus arrhythmia were stable across postures and (b) heart rate reactivity was significantly related to preejection period and respiratory sinus arrhythmia reactivity, whereas the latter two measures were unrelated. Reactivity classifications may therefore be significantly improved by attention to concurrent estimates of the activity of both autonomic branches.     

Vagal function indexed by respiratory sinus arrhythmia and cholinergic anti-inflammatory pathway

The autonomic nervous system, in particular vagal function, plays an important role in a wide range of somatic and mental disorders. Cardiac vagal function can be indexed by the respiratory sinus arrhythmia (RSA) – oscillations in heart rate linked to respiration mediated predominantly by fluctuations of vagus nerve efferent traffic originating in the nucleus ambiguus. Moreover, the neurocardiac vagal modulation has been shown to be related to physiological adaptability/flexibity and emotional regulation. Thus, greater vagal withdrawal during stressors and subsequent recovery should be indicative of a more flexible physiological response system.     

Resting respiratory sinus arrhythmia in suicide attempters

Although suicide attempts (SA) occur across a broad range of diagnoses as well as in the absence of a diagnosable disorder, most studies to date have focused on them within a single, specific disorder. Consistent with the NIMH RDoC initiative to identify biobehavioral vulnerabilities that cut across diagnoses, the goal of the present study was to examine potential differences in resting respiratory sinus arrhythmia (RSA) levels in a large, diagnostically heterogeneous sample of women with and without a history of SA who were matched on a broad range of demographic and clinical variables. Participants were 112 women with (n = 56) and without (n = 56) a history of SA recruited from the community. The two groups were equated on approximate age, race, household income, and lifetime histories of psychiatric diagnoses. Resting electrocardiogram was recorded during a 2‐min rest period. RSA was calculated via spectral power analyses with a fast Fourier transform. We found that women with a history of SA exhibited significantly lower resting RSA levels than women with no history of SA, and this difference was maintained even after statistically controlling for the potential influence of women's history of psychiatric diagnoses and their current symptoms of depression and anxiety. These findings suggest the presence of a link between resting RSA and SA history.     

The effects of respiratory sinus arrhythmia on anger reactivity and persistence in major depression

The experience of anger during a depressive episode has recently been identified as a poor prognostic indicator of illness course. Given the clinical implications of anger in major depressive disorder (MDD), understanding the mechanisms involved in anger reactivity and persistence is critical for improved intervention. Biological processes involved in emotion regulation during stress, such as respiratory sinus arrhythmia (RSA), may play a role in maintaining negative moods. Clinically depressed (MDD; n = 49) and nondepressed (non‐MDD; n = 50) individuals were challenged with a stressful computer task shown to increase anger, while RSA (high frequency range 0.15–0.4 Hz) was collected. RSA predicted future anger, but was unrelated to current anger. That is, across participants, low baseline RSA predicted anger reactivity during the task, and in depressed individuals, those with low RSA during the task had a greater likelihood of anger persistence during a recovery period. These results suggest that low RSA may be a psychophysiological process involved in anger regulation in depression. Low RSA may contribute to sustained illness course by diminishing the repair of angry moods.     

Respiratory sinus arrhythmia as a measure of cognitive workload

The current standard for measuring cognitive workload is the NASA Task-load Index (TLX) questionnaire. Although this measure has a high degree of reliability, diagnosticity, and sensitivity, a reliable physiological measure of cognitive workload could provide a non-invasive, objective measure of workload that could be tracked in real or near real-time without interrupting the task. This study investigated changes in respiratory sinus arrhythmia (RSA) during seven different sub-sections of a proposed selection test for Navy aviation and compared them to changes reported on the NASA-TLX. 201 healthy participants performed the seven tasks of the Navy's Performance Based Measure. RSA was measured during each task and the NASA-TLX was administered after each task. Multi-level modeling revealed that RSA significantly predicted NASA-TLX scores. A moderate within-subject correlation was also found between RSA and NASA TLX scores. The findings support the potential development of RSA as a real-time measure of cognitive workload.     

Better quantification of neonatal respiratory sinus arrhythmia—progress by modelling and model-related physiological examinations

A large interindividual variability of parameters quantifying respiratory sinus arrhythmia were found in a well defined group of healthy neonates during constant conditions of examination. Reasons for this can be found by means of a mathematical model which is based on physiological data. The results indicate sharp inconsistencies in the transfer function between respiratory movements and resulting respiratory sinus arrhythmia and are dependent on a relative frequency unit f_N (ratio of mean respiration rate to mean heart rate). The values of the coherence (as a function of this relative frequency unit) between respiratory movements and heart rate are also distinguished by a systematic decrease from lower to higher f_N values (f_N=0·1–0·5) and inconsistencies in modelling as well as in physiological examinations. The reasons for both effects can be demonstrated. The study is the basis of a new qualitative step of quantification of respiratory sinus arrhythmia in neonates by power spectral and coherence analyses.