心率变异性生物反馈对高血压前期患者应激反应的干预效果

目的探讨心率变异性生物反馈（HRV BF）干预高血压前期患者心血管应激反应的效果。方法比较高血压前期者与正常血压者应激反应上血压变化的差异;将36位高血压前期受试者随机分为心率变异性生物反馈（HRV BF）组、慢腹式呼吸（SAB）组和空白对照组。干预组受试者接受每次30 min,每周2次,持续2个月共15次的训练;空白对照组不予干预。实验间隔期嘱受试者每天进行不少于20 min的家庭训练。所有受试者在实验开始前及实验结束后均接受连续2 d同一时间点进行的两种应激测试。结果高血压前期者较正常血压者在应对心算应激时收缩压和舒张压反应性更大。干预2个月后,HRV BF和SAB组收缩压和舒张压平均降压幅度分别为15.4/10.2 mmHg、11.6/7.4 mmHg;空白对照组干预后血压无明显变化。HRV BF能显著降低受试者心算应激时收缩压反应性,较SAB更为明显。结论高血压前期者应激反应性较高,HRV BF训练可以降低受试者应对心理应激时心血管的反应,并降低高血压前期者血压。     

Effects of prenatal cocaine exposure and maternal separation on heart rate,orienting response habituation,and retention

Effects of the presence or absence of the dam during testing and the retention interval on pretone heart rate (HR) and habituation and retention of an HR orienting response to tone were examined in prenatally cocaine-exposed and nontreated Sprague Dawley rat pups in two experiments. On postnatal day 16, each pup received two test sessions, separated by a 4-hr retention interval during which pups were either isolated or placed with their dam and siblings. For testing, each pup was placed in the test apparatus in the presence or absence of an anesthetized dam where, after a 15-min adaptation period, 10 tone presentations were given, each separated by a 65-s intertrial interval, with HR measured during a 5-s pretone period and throughout the 10-s tone for each trial. Experiment 1 used offspring from the regular breeding colony and observed the typical HR lowering effect of maternal presence during testing, an effect that was surprisingly potentiated, however, following the retention interval in animals that were isolated during this interval. This apparent potentiation by prior isolation of the HR lowering effect of the dam was confirmed in Experiment 2 in nontreated offspring, but did not emerge convincingly in offspring of either dams subcutaneously injected with 40 mg/kg of cocaine HCl daily from gestational days 8 to 20 (C40) or dams injected with saline and pair-fed 4 days (PF4) to mimic the acute anorexic effects of cocaine administration. Consistent with prior work, C40 offspring also were found to exhibit better retention of the habituated orienting response than offspring of NT dams and to some extent PF4 dams as well, a retention effect that was not significantly influenced, however, by social context during the retention interval.     

Effects of emotions on heart rate asymmetry

Heart rate asymmetry (HRA) is an index that accounts for an uneven contribution of decelerations and accelerations to the heart rate variability (HRV). Clinical studies indicated that HRA measures have additive clinical value over the more frequently used HRV indexes. Despite the abundance of studies on psychological influences on HRV, little is known whether psychological factors influence HRA. Based on previous research regarding HRA and stress, we expected that negative emotions compared to positive emotions would decrease the contribution of decelerations to HRV. Thirty female participants watched three clips that produced negative emotions, positive emotions, and neutral affect. Besides electrocardiogram, we measured several physiological and behavioral responses to ascertain the affective impact of the clips. Using the RR interval time series, we calculated HRV and HRA indexes. We found that HRA differentiated between positive emotions and negative emotions reactivity. Positive emotions produced a higher number of decelerations in short‐term variability to the total short‐term variability (C1_d) compared to negative emotions. Moreover, C1_d correlated with subjective ratings of affect. In sum, the results of this study indicated that HRA is sensitive to psychological influences. HRA indexes are likely to contribute to a more nuanced physiological differentiation between emotions.     

Comparison of heart rate response and heart rate recovery after step test among smoker and non-smoker athletes

BackgroundExercise performance depend on the ability of the cardiovascular system to respond to a wide range of metabolic demands and physical exertion.ObjectivesTo investigate the habitual smoking effects in heart rate response and heart rate recovery after step test in athletes.MethodsSeventy-eight physically healthy active athletes (45 non-smokers and 33 smokers) aging 27±8 years old, participated in this study. All participants completed the International Physical Activity Questionnaire and performed the six-minute step test. Cardiovascular parameters such (resting heart rate, peak heart rate, heart rate at 1 min after testing, heart rate recovery, recovery time, blood pressure at rest, and post-testing blood pressure) were recorded.ResultsSmoker-athletes had higher resting heart rate (76 ± 9bpm vs. 72 ± 10bpm, p<0.05), maximum heart rate (154 ± 18bpm vs. 147 ± 17bpm, p<0.05) and recovery time (7min 25sec ± 6min 31sec vs. 4min 21sec ± 4min 30sec, p<0.05) than non-smoker athletes. Scores from the IPAQ were approximately the same (M=7927 ± 10303, M= 6380 ± 4539, p<0.05).ConclusionSmoking was found to affect athletes'' cardiovascular fitness. The change of the athletes'' heart rate recovery and recovery time contributes to the adaptation of cardiovascular function in training requirements.     

Effects of maternal breathing rate, psychiatric status, and cortisol on fetal heart rate

Women's experiences during pregnancy are predictive of variation in neurobehavioral profiles in their children. Few studies have assessed these relationships during the prenatal period. In 113 women in the 36^th –38^th gestational week (mean age 26.3 ± 5.4 years), electrocardiogram, blood pressure, respiration, salivary cortisol, and fetal heart rate (HR) were measured during baseline, a psychological challenge (Stroop color–word matching task), and a standardized paced breathing protocol. Subjects underwent the Structured Clinical Interview for DSM‐IV prior to testing and were grouped as: depressed, co–morbid for depression and anxiety, anxiety disorder only, and control. There was a significant main effect of maternal diagnostic group on fetal HR only during the Stroop task: fetuses of women in the co–morbid group had a greater HR increase compared to controls (p < .05). Overall, fetuses showed robust increases in HR during paced breathing (p < .0001), and there was no significant difference by maternal diagnosis. For both tasks, changes in fetal HR were independent of women's concurrent cardiorespiratory activity. Finally, although cortisol was higher in the co‐morbid group (p < .05), across all participants, there was a trend for maternal baseline cortisol to be positively associated with average fetal HR (p = .06). These findings indicate that variation in fetal HR reactivity—an index of emerging regulatory capacities—is likely influenced by multiple acute and chronic factors associated with women's psychobiology. © 2010 Wiley Periodicals, Inc. Dev Psychobiol 53:221–233, 2011.     

咖啡摄入前后心率变异性的对比研究

目的研究中等剂量咖啡摄入对青年受试者心率变异性的影响,明确咖啡对心脏自主神经活性的作用。方法无咖啡因摄入习惯的16名健康青年受试者(身高167 cm±7.2 cm、体重61.3 kg±6.3kg、年龄24.9岁±2.8岁)参与本项研究,在摄入含6 mg/kg咖啡因的咖啡饮品后,于8:40~10:45应用动态心电图记录仪(Holter)进行咖啡摄入前后心电信号的采集及心率(heart rate,HR)和心率变异性指标的分析。心率变异性指标包括R-R间期标准差(SDNN)、相邻R-R间期差值的均方根值(r MSSD)、相邻的R-R间期之差大于50 ms的心搏数占总心搏数的百分比(PNN50)、标化低频(normalized low frequency power,LFnorm)、标化高频(normalized high frequency power,HFnorm)、低频功率(low frequency,LF)与高频功率(high frequency,HF)的比值(LF/HF)。结果饮用咖啡后,心率、心率变异性指标均发生改变且具有统计学意义,HR、LFnorm和LF/HF分别降低了7.5%、17%和35%。r MSSD、PNN50和HFnorm分别提高了82%、80%和58%。其中HR及LF/HF随着时间的变化趋势最明显。HRV参数在饮用咖啡前后的差值ΔLF与ΔHF,ΔLF与ΔLF/HF均显著相关,相关系数为-0.980和0.903。结论中等剂量咖啡可引起心率变异性的改变和心率的降低,抑制交感神经活性,提高副交感神经活性。     

Foetal heart rate power spectrum response to uterine contraction

Cardiotocography is the most diffused prenatal diagnostic technique in clinical routine. The simultaneous recording of foetal heart rate (FHR) and uterine contractions (UC) provides useful information about foetal well-being during pregnancy and labour. However, foetal electronic monitoring interpretation still lacks reproducibility and objectivity. New methods of interpretation and new parameters can further support physicians’ decisions. Besides common time-domain analysis, study of the variability of FHR can potentially reveal autonomic nervous system activity of the foetus. In particular, it is clinically relevant to investigate foetal reactions to UC to diagnose foetal distress early. Uterine contraction being a strong stimulus for the foetus and its autonomic nervous system, it is worth exploring the FHR variability response. This study aims to analyse modifications of the power spectrum of FHR variability corresponding to UC. Cardiotocographic signal tracts corresponding to 127 UC relative to 30 healthy foetuses were analysed. Results mainly show a general, statistically significant (t test, p<0.01) power increase of the FHR variability in the LF 0.03–0.2 Hz and HF 0.2–1 in correspondence of the contraction with respect to a reference tract set before contraction onset. Time evolution of the power within these bands was computed by means of time-varying spectral estimation to concisely show the FHR response along a uterine contraction. A synchronised grand average of these responses was also computed to verify repeatability, using the contraction apex as time reference. Such modifications of the foetal HRV that follow a contraction can be a sign of ANS reaction and, therefore, additional, objective information about foetal reactivity during labour.     

哌甲酯控释剂治疗对注意缺陷多动障碍儿童父母压力的影响

目的:探讨哌甲酯控释剂(OROS-MPH)治疗对注意缺陷多动障碍(attention deficit hyper-activity disorder,ADHD)患者临床症状和父母压力的影响。方法:采用自身对照研究设计,对符合美国精神障碍诊断与统计手册第四版(Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition,DSM-IV)诊断标准的73名ADHD患者(年龄6~15岁),使用哌甲酯控释剂(18~54mg/d)治疗8周。以父母填写的IOWA Conners量表及研究者填写的ADHD症状评定问卷评估患者的临床症状,并作为主要临床疗效评价指标,以父母填写的父母压力指数量表(Parenting Stress Index,PSI)来评估父母的压力,分别在基线、治疗4周末和8周末用以上问卷进行评估。结果:66名ADHD患儿完成了8周的治疗。经哌甲酯控释剂治疗后,ADHD患者IOWA Conners量表中的注意缺陷/多动因子分、对立/违抗因子分和总分随治疗时间下降(均P<0.001);ADHD症状评定问卷的注意缺陷因子分、多动冲动因子分和总分较服药前下降(均P<0.001);PSI量表的压力总分随时间明显下降(P<0.01),PSI量表中儿童方面分量表中,适应性、父母的接受度、要求、心境、注意不能/多动、父母的强制性6个因子得分均随着时间下降(均P<0.01);在父母方面分量表中,抑郁、角色的限制、配偶关系、孤独、健康状况5个因子得分均随着时间显著下降(均P<0.01)。基线时PSI总分与IOWA Conners量表总分、ADHD症状评定问卷总分呈正相关(r=0.346~0.902,均P<0.01)。结论:哌甲酯控释剂治疗能有效改善ADHD患者的临床症状和改善患者及其父母的压力,提高社会功能。     

Central apnoeas have significant effects on blood pressure and heart rate in children

Brief central apnoeas (CAs) during sleep are common in children and are not usually considered clinically significant unless associated with oxygen desaturation. CAs can occur spontaneously or following a movement or sigh. The aim of this study was to investigate acute cardiovascular changes associated with CAs in children. Beat‐by‐beat mean arterial pressure (MAP) and heart rate (HR) were analysed across CAs, and spontaneous and movement‐induced events were compared using two‐way analysis of variance with post hoc analyses. Fifty‐three children (28 male/25 female) aged 7–12 years referred for investigation of sleep‐disordered breathing (SDB) and 21 age‐matched healthy controls (8 male/13 female) were studied. Children underwent routine clinical polysomnography with continuous blood pressure (BP) recordings. Movement‐induced, but not spontaneous, CAs were more frequent in children with mild or moderate/severe obstructive sleep apnoea (OSA) compared with healthy controls (P < 0.05 for both). Movement‐induced CAs were associated with significantly larger MAP and HR changes across the event compared with spontaneous CAs. The percentage changes in MAP and HR between late‐event and post‐event were significantly greater for movement‐induced compared with spontaneous CAs (MAP 20.6 ± 2.3 versus 12.2 ± 1.8%, P < 0.01; HR 28.2 ± 2.6 versus 14.7 ± 2.5%, P < 0.001). This study demonstrates that movement‐induced CAs are more common in children with OSA, and are associated with significantly greater changes in HR and BP compared with spontaneous CAs. These data suggest that movement‐induced CAs should be considered when assessing the cardiovascular impact of SDB.     

Differences in pulse rate and heart rate and effects on the calculation of heart rate reactivity during periods of mental stress

Heart rate and reactivity from pulse and ECG were compared over rest and mental arithmetic periods of 2-min duration each for 32 males and 50 females. Data from the two sources of heart rate were not significantly different during the rest period but did differ significantly during periods of heart rate acceleration and deceleration. Sex effects were also noted, with females having consistently higher heart rates from both sources of measurement. Calculation of heart rate reactivity via five procedures based upon the wider literature revealed significant differences between data from different sources of heart rate. Implications for assessment of heart rate reactivity to laboratory stressors are discussed, with suggestions for future research.     

Effects of redundant and nonredundant bimodal sensory stimulation on heart rate in bobwhite quail embryos

Research with both animal embryos and human infants has provided evidence that information presented redundantly and in temporal synchrony across sensory modalities (intersensory redundancy) can guide selective attention, perceptual learning, and memory during early development. How this facilitation is achieved remains relatively unexamined. This study examined the effects of redundant versus nonredundant bimodal stimulation on a measure of physiological arousal (heart rate) in bobwhite quail embryos. Results show that quail embryos exposed to concurrent but nonredundant auditory and visual stimulation during the late stages of incubation exhibit significantly elevated heart rates following stimulus exposure and during stimulus reexposure when compared to embryos exposed to redundant and synchronous audiovisual stimulation, unimodal auditory stimulation, or no supplemental prenatal sensory stimulation. These findings indicate a functional distinction between redundant and nonredundant bimodal stimulation during early development and suggest that nonredundant bimodal stimulation during the prenatal period can raise arousal levels, thereby potentially interfering with the attentional capacities and perceptual learning of bobwhite quail. In contrast, intersensory redundancy appears to foster arousal levels that facilitate selective attention and perceptual learning during prenatal development.     

Cortical thickness,resting state heart rate,and heart rate variability in female adolescents

Resting state heart rate variability (HRV) is a psychophysiological marker that has gained increasing research interest, in particular in developmental neuroscience. HRV has been shown to be associated with mental and physical health, beyond simple measures of heart rate (HR) and shows inter‐ and intraindividual variance across aging. Recently, three studies reported on a positive correlation between resting state HRV and cortical thickness in selected regions of interest (ROIs) in adult samples. Structural thickness, HRV, and HR change during the sensitive period of adolescence. Previously, no study has addressed the structural concomitants of resting HR and HRV in adolescents. Cortical thickness (3‐T MRI), HR, and HRV were recorded in 20 healthy, female adolescents (mean age: 15.92 years; SD = 1.06; range: 14–17). In line with existing research in adults, cortical thickness in a number of ROIs was associated with resting state HRV but not HR. The comparison of regression analyses using the Bayes factor revealed evidence for a correlation between HRV and cortical thickness of the bilateral rostral anterior cingulate cortex. However, unlike in adults, greater cortical thickness was associated with reduced HRV in female adolescents. Analyses on HR showed no superior model fit. Results suggest that greater HRV might be beneficial for cortical development during adolescence (cortical thinning). On the other hand, cortical development might determine changes in autonomic nervous system function in adolescents. Future studies are needed to replicate these findings in larger samples including boys and to test these hypotheses in longitudinal designs.     

Cardiorespiratory response to spontaneous cortical arousals during stage 2 and rapid eye movement sleep in healthy children

Arousal from sleep is associated with transient and abrupt cardiorespiratory changes, and elevated arousals associated with sleep disorders may trigger adverse cardiovascular sequela. In this paper, we provide the first data in children on cardiorespiratory responses to cortical arousal. Heart rate and ventilatory responses to arousal from stage 2 and rapid eye movement (REM) sleep were investigated in 40 normal, healthy Caucasian children (age: 7.7 ± 2.6 years; body mass index z‐score: 0.30 ± 0.8). All children underwent overnight polysomnography studies. Cortical arousals were scored according to standard criteria. Heart rate changes were assessed over 30 s, starting 15 s prior to cortical arousal onset. Breathing rates were quantified three breaths before and after arousal onset. Arousals from stage 2 as well as REM sleep resulted in an R–R interval shortening of about 15%, independent of age and gender. The R–R interval shortening initiated at least 3 s before the cortical arousal onset. The breathing interval immediately after cortical arousal onset was significantly shortened (P < 0.001). In conclusion, cortical arousals in children are associated with an increase in breathing rate and significant heart rate accelerations, which typically precede the cortical arousal onset.     

低氘白酒对人体心率变异性和自主神经的调控作用

目的研究连续8 d急性摄入不同剂量自制酒精饮料、传统白酒和低氘白酒对人体心率变异性(HRV)和自主神经调控作用。方法 11例健康成年男性志愿者,体质量(64.7±4.5)kg,年龄21~25岁,平均年龄23.7岁。分为7个试验组,1本底(对照)(CK组),不饮用任何含酒精饮品;2低剂量酒精(A-L组),每天饮用50 m L 52度自制酒精+200 m L普通饮用水;3高剂量酒精(A-H组),每天饮用100 m L 52度自制酒精+200 m L普通饮用水;4低剂量白酒(L-L组),每天饮用50 m L52度泸州老窖特曲+200 m L普通饮用水;5高剂量白酒(L-H组),每天饮用100 m L 52度泸州老窖特曲+200 m L普通饮用水;6低剂量低氘白酒(DDL-L组),每天饮用50 m L 52度泸州老窖特曲+200 m L低氘水;7高剂量低氘白酒(DDL-H组),每天饮用100 m L 52度泸州老窖特曲+200 m L低氘水。连续8 d。用心动周期信号(HPS)分析系统检测饮酒半小时后受试者的HRV,以评价交感神经和副交感神经系统活动。结果饮用自制酒精饮料和传统白酒使自主神经的交感神经活性及迷走神经活性变化,以交感神经活性升高最为突出活性。饮用低氘白酒后未见有交感和迷走神经活性的明显变化,即HRV的波动。结论相对于自制酒精饮料和传统白酒,低氘白酒能使人体自主神经协调和平衡性维持在较高水平。     

冠状动脉追踪冻结技术对高心率儿童冠状动脉成像质量的改善

目的:探索第二代冠状动脉追踪冻结（SSF2）技术是否可以提升高心率儿童冠状动脉的形态分辨能力。方法:对53例心率≥75次/min患儿行冠状动脉CT血管成像,年龄平均（17.5±18.7）个月,平均体质量（10.68±5.13） kg,扫描电压80、100 kV,采用智能心电门控技术自动选择曝光期相。将原始数据分别重建为3组图像:A组为常规图像;B组为采用SSF1技术的重建图像;C组为采用SSF2技术的重建图像。对3组冠状动脉图像的质量评分及可诊断率进行评估。结果:53例共评价534个冠状动脉节段。B组与C组右冠状动脉、左前降支、冠状动脉起源和冠状动脉评分及可诊断率差异均有统计学意义（P均<0.05）,左回旋支（LCX）评分差异有统计学意义（P<0.05）,LCX可诊断率无统计学意义（P=0.05）。A组与B组左前降支、LCX和冠状动脉起源评分差异均无统计学意义（P=0.07、0.14、0.43）。结论:采用SSF2技术可进一步改善高心率患儿冠状动脉CT血管成像质量。     

Effects of smoking on heart rate,anxiety, and feelings of success during social interaction

The effects of smoking on heart rate (HR) and emotional processes during social interactions were assessed in 12 smokers. Smoking was associated with less anxiety and with enhanced feelings of being successful both in changing the opinions of others and in expressing one's own point of view. These findings are consistent with others in the literature. The increase in HR during social interactions in which the participants smoked was similar in magnitude to the HR increase associated with speaking versus listening during conversation. The effects of smoking and social interaction on HR appeared to be additive. Smoking during the social interaction increased HR only about half as much as is typically reported for smokers seated quietly in nonsocial situations     

呼吸对心率变异性的影响

呼吸是心率变异性(HRV)的一个重要影响因素。简要介绍了呼吸影响HRV的机制,综述了呼吸频率、呼吸深度和呼吸模式对HRV各种参数的影响,以及病理条件下呼吸对HRV影响的变化。指出了用HRV判断心脏生理状态应考虑到呼吸的影响。     

Effects of methylphenidate on quantitative EEG of boys with attention-deficit hyperactivity disorder in continuous performance test

The purpose of this study was to investigate the effects of methylphenidate, a psychostimulant, on quantitative electroencephalography (QEEG) during the continuous performance test (CPT) in boys with attention-deficit hyperactivity disorder (ADHD). The QEEG was obtained from 20 boys with ADHD. The amplitudes of 4 bands (alpha, beta, delta, and theta) in the QEEG, as well as the theta /beta ratio, before and after the administration of methylphenidate were compared during both the resting and CPT states. Methylphenidate induced a significant increase of alpha activities in both the right and left frontal and occipital areas, an increase of beta activities in almost all areas except for the temporal region, a decrease of theta activities in both the occipital and right temporo-parietal areas, a mild decrease of delta activities in the occipito-parietal areas, and an increase of the theta/beta ratio in the right frontal and parieto-occipital, and left temporal areas during the CPT state. No significant QEEG changes were induced by the administration of methylphenidate in the resting state. These data suggest that methylphenidate has greater electrophysiological influences on the cerebral topographical activities during the performance of attentional tasks, as compared to the resting state, in boys with ADHD.     

Aggression and cardiovascular response in children

OBJECTIVE: To examine cardiovascular response as a function of children's aggression after controlling for the effects of known risk factors. METHOD: Participants were 140 children in second, fourth, and sixth grades. Teachers completed the Matthews Youth Test for Health, a measure that includes questions pertaining to children's aggression. Measures of blood pressure and heart rate were obtained during baseline, academic quiz, and recovery. RESULTS: Increasing age and body mass index were associated with increased cardiovascular responses. Aggressive children exhibited higher heart rates at baseline and lower heart rate reactivity. Aggressive children with a positive parent history of hypertension exhibited the greatest cardiovascular response. CONCLUSIONS: These results provide further support for the identification of behavioral factors that increase cardiovascular risk in children.