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1.
The QT interval of the electrocardiogram, although often coordinated in an inverse relationship to heart rate, appears from the existing evidence to be regulated by mechanisms separate from those that govern heart rate. The purpose of this inquiry was to explore further the relationship of the two and to test other factors that may contribute to the regulation of QT. Heart rate and QT duration were measured in healthy human subjects during postural change and exercise. The data showed that, while coordinated in an inverse relationship under some circumstances, under others heart rate and QT were discordant, leading to the inference that there is no fixed linkage between the two. Previous work by the authors and other published studies have suggested that ventricular contractility may have more predictable association with QT shortening than do increases in heart rate. Observations of force of ventricular contraction (HI and IJ velocity) as reflected in ballisto-cardiographic tracings were made using each of 12 human subjects as the authors' own control. The data revealed a highly significant correlation between the velocity measures and QT duration (p less than 0.01) but not heart rate. These findings led to the conclusion that there is clearly not a fixed relationship between heart rate and QT interval and to the hypothesis that QT may more closely reflect the degree of cardiac contractility.  相似文献   

2.
The QT interval of the electrocardiogram, although often coordinated in an inverse relationship to heart rate, appears from the existing evidence to be regulated by mechanisms separate from those that govern heart rate. The purpose of this inquiry was to explore further the relationship of the two and to test other factors that may contribute to the regulation of QT. Heart rate and QT duration were measured in healthy human subjects during postural change and exercise. The data showed that, while coordinated in an inverse relationship under some circumstances, under others heart rate and QT were discordant, leading to the inference that there is no fixed linkage between the two. Previous work by the authors and other published studies have suggested that ventricular contractility may have more predictable association with QT shortening than do increases in heart rate. Observations of force of ventricular contraction (HI and IJ velocity) as reflected in ballisto-cardiographic tracings were made using each of 12 human subjects as the authors’ own control. The data revealed a highly significant correlation between the velocity measures and QT duration (p<0.01) but not heart rate. These findings led to the conclusion that there is clearly not a fixed relationship between heart rate and QT interval and to the hypothesis that QT may more closely reflect the degree of cardiac contractility.  相似文献   

3.
The purpose of this study was to compare two methods of analyzing the effects of exteroceptive feedback training on the voluntary bidirectional control of human cardiac rate with the use of a within-subject control design. In this design heart rate (HR) during an experimental period (increase or decrease) is compared with that recorded during some other control period, generally a baseline “rest” period. Ten male undergraduates were instructed to control HR and given visual feedback of heart activity. Trials on which Ss were to raise and to lower HR were both given in a single training session. The data were analyzed in two ways: (a) cardiac rate during HR control periods was compared to an initial pre-experiment baseline; (b) cardiac rate during HR control periods was compared to a running pretrial baseline. The results support the argument that the former procedure fails to take account of habituating levels of cardiac rate and favors finding large magnitude decreases in HR but small increases, whereas the latter procedure favors finding large magnitude increases but small decreases. It is suggested that magnitude of directional control will be artifactual when initial values are used to assess change. Contaminating influences on the running pretrial baseline were also discussed.  相似文献   

4.
The primary objective of the present study was to assess the utility of (1) comorbid depression and (2) parasympathetic influence on cardiac function as markers for treatment response among aggressive preadolescent males. Inpatient records of 53 patients with conduct disorder and attention deficit hyperactivity disorder (17 with a comorbid depressive disorder) were examined, including an intake electrocardiogram and daily tallies of several indices of aggressive behavior across 3 weeks of stay. The relations of comorbid depression, heart rate variability, and residualized heart rate (primarily of sympathetic origin) to treatment response were assessed through analyses of linear growth functions. Significant vagal tone by diagnostic status interactions were obtained for both frequency and duration indices of aggression, whereby nondepressed patients with high vagal tone deteriorated and depressed patients with high vagal tone improved during hospitalization. No such relation was found for attention deficit hyperactivity disorder symptoms. Patients in the comorbid group also exhibited greater heart rate variability than their nondepressed counterparts. Furthermore, residualized heart rate was predictive of maternal substance use and paternal incarcerations. These findings suggest complex relations among treatment response, comorbid depression, and emotion regulation in male preadolescents with severe behavior disorders. Additionally, the differential prediction afforded by vagal tone and residualized heart rate underscores the importance of assessing both parasympathetic and sympathetic indices of cardiac function as distinct physiological markers. Aggr. Behav. 26:425–441, 2000. © 2000 Wiley‐Liss, Inc.  相似文献   

5.
The study investigated the dynamic relation between contingency learning and heart rate with risk and non‐risk babies 5‐ to 10‐months‐old. Four groups were compared in a two contingency treatments (contingent, yoked) × two risk status design. Concurrent heart rate was monitored during three phases of a contingency learning task (baseline, contingency/stimulation, extinction) and analysis focused on phase transitions. Non‐risk babies presented with contingent stimulation showed an immediate increase in cardiac rate associated with a subsequent response increase to the contingency. Risk infants presented with contingent stimulation showed delayed cardiac reactivity accompanied by a smaller response increase to the contingency. Yoked controls decreased responding in the contingent period with no significant changes in cardiac reactivity at phase transitions. The findings of the study are discussed in relation to individual differences in physiological regulation and to differential sensitization in a contingency learning task.  相似文献   

6.
Depression prevalence is between 15% and 20% in coronary heart disease patients, such as those with angina, or after a myocardial infarction or coronary artery bypass graft surgery. The presence of depression places a coronary heart disease patient at twofold higher risk for further major cardiac events and death, as well as poor quality of life and early exit from the labour force. As a consequence, several learned societies, including the National Heart Foundation of Australia, have published guidelines that recommend questionnaire screening to improve identification and management strategies for depression in coronary heart disease patients. Psychologists in hospitals, community settings, and private practice can have a key role in the realisation of the National Heart Foundation of Australia's aims. We review the recent guidelines and outline implications for psychologists to identify and manage depression in coronary heart disease patients. The evidence reviewed suggests that cognitive‐behavioural therapy and problem‐solving therapy are frontline non‐pharmacological interventions for depression in CHD patients.  相似文献   

7.
This study assessed the physiological and cognitive effects of Valins' (Valins, S. Journal of Personality and Social Psychology, 1966, 4, 400–408) false heart rate procedure. Twenty-two male subjects were exposed to two feedback conditions during which measures of actual heart rate and skin conductance were obtained. In each condition, eight slides of nude females were presented; some slides were associated with false heart rate increases, while for other slides the feedback remained stable. In one condition, subjects were told that the heart rate was that of another subject; in the other condition, subjects were told that the feedback was their own heart rate. In both conditions, subjects judged the attractiveness of the slides from their own point of view and from the point of view of the other subject. Slides associated with false heart rate increases were rated as more attractive than stable slides when subjects (1) heard their own heart rate and rated their own attraction; (2) heard the other subject's heart rate and rated their own attraction; and (3) heard the other subject's heart rate and rated the other subject's attraction. Skin conductance responses and actual cardiac decelerations were greater when subjects heard what was allegedly their own heart rate and when the slides were accompanied by apparent cardiac acceleration. However, these actual physiological responses did not play a causal role in relation to the affective judgments. Instead, the relationship between perceived physiological changes and feelings of attractiveness was mediated by cognitive processes associated with informational and directive influences of the feedback.  相似文献   

8.
The several functions that a stimulus can assume were investigated in a Pavlovian conditioning procedure. The subjects were six rhesus monkeys; the response under observation was heart rate. The conditioning began with a temporal separation of zero between a signal and a regularly repeating electric shock; the signal was then moved to a series of earlier locations in the inter-shock interval. After six sessions at each location, two sessions followed in which only the shock was delivered periodically. The findings included: (1) A two-phased conditioned cardiac rate response seen at the first location became more multiphasic and irregular during longer intervals between signal and shock; (2) the location where the conditioned response peaked became increasingly variable as the signal was moved back, but this variability maintained a constant proportion to the signal-shock interval; and, (3) heart rate during a presignal period, and during a comparable period in shock only sessions, was generally deceleratory early in training and acceleratory thereafter. Sessions with the signal showed heart rate in the presignal period to have become acceleratory earlier in training than sessions with shock only. The data pertain to stimulus control over heart rate as a function of: (A) the temporal proximity of a signal to an aversive stimulus; and, (B) the presence or absence of the signal. The use of appropriate response units in cardiac conditioning is also discussed.  相似文献   

9.
越来越多的冠心病患者接受经皮冠状动脉介入治疗,但是这些患者表现出的焦虑抑郁情绪对经皮冠状动脉介入治疗(PCI)围术期的影响却少有报道。研究发现,焦虑和抑郁对心脏事件发生后的恢复有不利的影响,而接受 PCI 治疗的患者情感障碍的发生率是比较高的。主要心血管事件与这些负面影响是相关联的,研究表明密切监测这些患者的情感状态可以明显改善临床预后。  相似文献   

10.
This study aimed to assess whether (1) a muscle tensing procedure which has been found to be useful in the treatment of blood-phobic patients produces an increase in heart rate and cerebral blood flow and (2) whether this increase is greater than that produced by mental effort alone. Subjects were 17 volunteers with a history of fainting in response to blood-injury stimuli, (12 were phobic) and 8 volunteers with no fainting history. They were required to (a) rest, (b) do mental arithmetic, and (c) repeatedly tense and release their arm and leg muscles. It was found that Ss, heart rate and cerebral blood flow velocity were significantly greater during the muscle tensing procedure than during mental arithmetic or resting conditions. The increased cerebral blood flow produced by muscle tensing may enable blood phobic patients to prevent fainting during exposure treatment.  相似文献   

11.
Persons who stutter often report their stuttering is influenced by emotional reactions, yet the nature of such relation is still unclear. Psychophysiological studies of stuttering have failed to find any major association between stuttering and the activity of the sympathetic nervous system. A review of published studies of heart rate in relation to stressful speech situations indicate that adults who stutter tend to show a paradoxical reduction of heart rate compared with nonstuttering persons. Reduction of heart rate has also been observed in humans and mammals during anticipation of an unpleasant stimulus, and is proposed to be an indication of anticipatory anxiety resulting in a "freezing response" with parasympathetic inhibition of the heart rate. It is suggested that speech-related anticipatory anxiety in persons who stutter is likely to be a secondary, conditioned reaction based on previous experiences of stuttering. EDUCATIONAL OBJECTIVES: The reader will be able to: (1) describe how the autonomic nervous system is modulated by emotional responses; (2) explain how anticipatory fear often results in inhibition of heart rate due to parasympathetic activation; (3) discuss why emotional reactions in persons who stutter may be secondary to negative experiences of speech problems.  相似文献   

12.
Tested 84 healthy, sedentary women in the laboratory during performance of difficult and easy problem-solving tasks. They were divided into three age groups: 19 to 32 years, 33 to 43 years, and 44 to 60 years (n = 28 women per group). Baseline systolic blood pressure (SBP) and diastolic blood pressure increased with age, whereas skin conductance level was lower in older women. In addition, initial SBP reactions to tasks were positively related to age, even after controlling for baseline blood pressure, aerobic fitness, and Framingham Type A Scale behavior scores. There were no differences in heart rate (HR) or "additional" HR reactions, so the anticipated decline in cardiac sympathetic response with age was not observed. The mechanisms underlying age-related reactions to mental stress are discussed.  相似文献   

13.
The present study examined the stability of cardiovascular reactions to psychological stress and cigarette smoking, and the extent to which cardiovascular reactions to stress were predictive of cardiovascular reactions to smoking. Thirty subjects were given an initial test involving two repetitions of mental arithmetic stress and paced smoking while blood pressure and heart rate were measured. Two months later, 26 of these subjects were retested in the same paradigm. Large and stable individual differences were observed in cardiovascular reactivity to both stress and smoking. Moreover, for systolic and diastolic blood pressure, but not heart rate, reactions to stress were modestly correlated with reactions to cigarette smoking. These results are consistent with the possibility that level of reactivity to cigarette smoking may constitute a risk factor for coronary heart disease, and that one or more common variables may mediate the magnitude of blood pressure reactivity to both stress and cigarette smoking.  相似文献   

14.
Studies of the cardiac orienting reflex in 16 dogs, moderately anesthetized and awake are reported. In the anesthetized dogs prominent transient heart rate decrease was commonly noted within one or two beats after the onset of various auditory stimuli, and less often after visual stimuli. This cardiac inhibition was neither as prominent nor as frequent in occurrence in awake dogs. The respiratory cycle at stimulus onset influenced the appearance and degree of heart rate decrease, with the greatest and most frequent decreases occurring during the expiratory phase. Atropine abolished the response. There was little evidence of habituation of this orienting response under anesthesia, although “waxing” and “waning” apparently related to minute-by-minute fluctuations in degree of unconsciousness, occurred. These findings are discussed in relation to neurophysiological and neuroanatomical correlates of orienting responses, hypotheses of orienting and attention and cardiovascular neurohumoral mediators.  相似文献   

15.
Our interest in cardiovascular conditioning, particularly the fact that conditional tachycardia has been observed in many dogs after only one or two combinations of conditional and unconditional stimuli, led us to investigate conditioning using a single application of an unconditional stimulus. Initially we studied the effect of orienting stimuli (soft tones) on the heart rate in 9 dogs. After 30–100 presentations of the tones alone, each dog received on one occasion a 25-volt shock (sufficient to cause yelping and struggling) to a leg as unconditional stimulus immediately following a tone. Thereafter 30–100 additional tones were presented with no further shock. Little or no heart rate change occurred during the orienting tones (before shock). Three types of cardiac changes occurred during experimental sessions after the shock: 1) Increased heart rate during the tones in 5 dogs; 2) Generalized lowering of heart rate during all experimental sessions after shock in 4 dogs; 3) Electrocardiographic changes during tones in 3 of the dogs also showing the generalized decrease in heart rate. No motor flexion conditional reflexes developed. Tones an octave different in pitch from the one associated with the shock also caused approximately the same heart rate changes, indicating lack of differentiation. This one-trial cardiac conditioning persisted after the single conditioning trial for more than a month in 2 dogs and for at least 3 to 5 sessions in the other dogs.  相似文献   

16.
We investigated the link between the eight basic emotions named by Plutchik and heart rate, heart-rate variability in the 114 patients, 86 men and 28 women (M = 53.8 yr., SD = 8.0) with acute coronary heart disease during the initial 24-hr. stay in the coronary care unit and again at hospital discharge. Variability in heart rate was significantly positively associated with scores on Trust (the emotional state acceptance) at hospital admission and discharge in the patients with unstable angina and non-Q-wave infarction, on Aggression in the patients with unstable angina at hospital discharge and at hospital admission in the patients with non-Q-wave infarction. There was inverse relation on Timid (the emotional state fear) and Gregarious (joy) at hospital admission and on Distrust (disgust or rejection), Depressed (sadness), and Dyscontrol (impulsiveness) at hospital discharge in the patient with non-Q-wave infarction. There was no significant association between heart-rate variability and the scores on the Emotion Profile Index in the patients with anterior and posterior myocardial infarction. There was no statistically significant association between heart rate and scores on the Emotion Profile Index in the patients with acute coronary disease at hospital admission and discharge. Our results suggest psychological interventions that enhance emotional states represented by the Trust and Aggression scales and minimize those represented by Depressed, Dyscontrol, Timid, and Distrust scales could have a beneficial effect on cardiovascular function in the patients with unstable angina and non-Q-wave infarction in a hospital setting.  相似文献   

17.
Influential models highlight the central integration of bodily arousal with emotion. Some emotions, notably disgust, are more closely coupled to visceral state than others. Cardiac baroreceptors, activated at systole within each cardiac cycle, provide short-term visceral feedback. Here we explored how phasic baroreceptor activation may alter the appraisal of brief emotional stimuli and consequent cardiovascular reactions. We used functional MRI (fMRI) to measure brain responses to emotional face stimuli presented before and during cardiac systole. We observed that the processing of emotional stimuli was altered by concurrent natural baroreceptor activation. Specifically, facial expressions of disgust were judged as more intense when presented at systole, and rebound heart rate increases were attenuated after expressions of disgust and happiness. Neural activity within prefrontal cortex correlated with emotionality ratings. Activity within periaqueductal gray matter reflected both emotional ratings and their interaction with cardiac timing. Activity within regions including prefrontal and visual cortices correlated with increases in heart rate evoked by the face stimuli, while orbitofrontal activity reflected both evoked heart rate change and its interaction with cardiac timing. Our findings demonstrate that momentary physiological fluctuations in cardiovascular afferent information (1) influence specific emotional judgments, mediated through regions including the periaqueductal gray matter, and (2) shape evoked autonomic responses through engagement of orbitofrontal cortex. Together these findings highlight the close coupling of visceral and emotional processes and identify neural regions mediating bodily state influences on affective judgment.  相似文献   

18.
Depressive symptoms in patients presenting with coronary heart disease have an impact on quality of life, health behavior, and prognosis. The psychotherapeutic interventions which had been tested for their efficacy in previous randomized controlled trials, showed only minor effects. A stepwise approach consisting of individual and group psychotherapeutic interventions was tested for efficacy in a German multicenter study. The presented paper describes the therapeutic procedure for two individual sessions and one couple session by means of case examples. The main focus was to determine depressive symptoms along with underlying maladaptive personality traits such as negative affectivity and social inhibition (type D pattern). Depressive mood, disappointments and mortifications both in private and professional life and also during the previous treatment are verbalized. Dysfunctional relation patterns and maladaptive sickness behavior are taken up by the psychotherapist and alternative behavior patterns are developed. The objective of the couple session is strengthening the partnership resources and offering relief of fears and worries relative to the heart disease. The psychotherapeutic procedure is psychodynamically oriented but also contains cognitive-behavioral and interactional treatment approaches.  相似文献   

19.
Early life adverse experiences have long-term physiologic and behavioral effects and enhance stress sensitivity. This study examined the effects of maternal separation (MS) on cardiac stress responsivity and structure in adulthood. Male Wistar rats were separated from the dams for 3?h per day from postnatal days 2 through 15. When exposed to 5-day intermittent restraint stress (IRS) as adults, MS, and control rats showed similar acute modifications of cardiac sympathovagal balance, quantified via heart rate variability analysis. In addition, MS had no effect on cardiac pacemaker intrinsic activity (as revealed by autonomic blockade with scopolamine and atenolol) and did not affect the circadian rhythmicity of heart rate, neither before nor after IRS. However, MS differed from control rats in cardiac parasympathetic drive following IRS, which was heightened in the latter but remained unchanged in the former, both during the light and dark phases of the daily rhythm. The evaluation of adult cardiac structure indicated that stress experienced during a crucial developmental period induced only modest changes, involving cardiomyocyte hypertrophy, increased density of vascular structures, and myocardial fibrosis. The mildness of these functional-structural effects questions the validity of MS as a model for early stress-induced cardiac disease in humans.  相似文献   

20.
In panic disorder bodily sensations appear to play an important role as a trigger for anxiety. In our psychophysiological model of panic attacks we postulate the following vicious circle: individuals with panic attacks perceive even quite small increases in heart rate and interpret these changes as being catastrophic. This elicits anxiety and a further increase in heart rate. To evaluate this model we conducted a field study of 28 subjects with panic attacks and 20 healthy controls. A 24 hr ambulatory ECG was recorded and the subjects were instructed to report any cardiac perceptions during this period and to rate the anxiety elicited by these perceptions. The incidence of cardiac perceptions was about the same in both groups, but only subjects with panic attacks reported anxiety associated with such perceptions. Analysis of the ECGs revealed that in both groups heart rate accelerations preceded cardiac perceptions. Following cardiac perceptions, the healthy controls showed a heart rate deceleration, whereas the subjects with panic attacks had a further acceleration. This heart rate increase after cardiac perceptions was positively related to the level of anxiety elicited by the perceptions. These results provide clear evidence in support of the vicious circle model of panic attacks.  相似文献   

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