Neuropeptide and cardiovascular responses to intravenous catheterization in normotensive and hypertensive blacks and whites

Research suggests that heightened cardiovascular and neuroendocrine (typically catecholamine) responses to stressors may lead to the development of hypertension and that there may be race differences in patterns of reactivity that are potentially pathogenic. Certain neuropeptides exert profound effects on blood pressure (BP) and heart rate (HR), yet no published studies have examined relationships between these peptides, hypertensive status, race, and reactivity. Seventeen Black and 20 White normotensive and borderline-hypertensive male 19- to 50-year-olds underwent intravenous catheterization while cardiovascular and neuropeptide responses to the stress of being catheterized were examined. Results indicate that, in response to the stressor, Black hypertensives, showed significantly lower endorphin levels compared to Black normotensives, and White hypertensives showed significantly higher levels of beta-endorphin compared to White normotensives. Groups were not significantly different in endorphin levels at recovery. Black hypertensives also showed significantly higher stressor-induced HR and systolic and diastolic BP compared to White hypertensives and normotensives. Lower levels of beta-endorphin and lower urine sodium excretion were associated with higher BP and HR.     

Blood pressure and personality

Three groups of 18-yr-old male Ss were selected from a representative Swedish population according to strict blood-pressure criteria: hypertensives (systotic blood pressure above 146 and diastolic above 90), on two occasions, normotensives (systolic blood pressure between 124 and 131, population mean = 128) and hypotensives (systolic blood pressure between 100 and 106). As a part of a broad multidisciplinary study, personality inventory scales and unpleasantness ratings for various types of situations were administered. The findings for the hypertensives indicated lower assertiveness and higher anxiety-proneness, whereas the hypotensives, compared to normotensives, showed a more impulsive, acting-out personality pattern. The hypertensive group was subdivided according to digital vasoconstriction criteria. The non-vasoconstricted subgroup showed a more impulsive and ‘anger-out’ personality pattern, whereas the pattern obtained in the vasoconstricted subgroup was more similar to the classical hypertensive personality, characterized by anxiety and unexpressed anger.     

Cardiovascular reactivity to psychological stress in aerobically trained versus untrained mild hypertensives and normotensives

Cardiovascular reactivity to video game and mental arithmetic stressors was compared among three groups of men: aerobically trained mild hypertensives, untrained mild hypertensives, and a comparison group of untrained normotensives. Relative to the untrained hypertensives, the trained hypertensives reacted to the video game with marginally smaller systolic blood pressure and diastolic blood pressure, but there were no significant differences between these groups in reactivity during the mental arithmetic task. Comparisons between each hypertensive group and the normotensive group showed that blood pressure (BP) reactivity of normotensives during the video game was generally similar to that of trained hypertensives but smaller than that of untrained hypertensives. These results indicate that aerobic training, which has been found to reduce resting BP in mild hypertensives, may also exert a favorable impact in reducing cardiovascular reactivity of hypertensives during some stressful situations.     

Poor emotional responsiveness in clinical hypertension: Reduced accuracy in the labelling and matching of emotional faces amongst individuals with hypertension and prehypertension

Psychological factors are known to play an important part in the origin of many medical conditions including hypertension. Recent studies have reported elevated blood pressure (even in the normal range of variation) to be associated with a reduced responsiveness to emotions or ‘emotional dampening’. Our aim was to assess emotional dampening in individuals with more extreme blood pressure levels including prehypertensives (N = 58) and hypertensives (N = 60) by comparing their emotion recognition ability with normotensives (N = 57). Participants completed novel facial emotion matching and facial emotion labelling tasks following blood pressure measurement and their accuracy of emotion recognition and average response times were compared. The normotensives demonstrated a significantly higher accuracy of emotion recognition than the prehypertensives and the hypertensives in labelling of facial emotions. This difference generalised to the task where two facial halves (upper & lower) had to be matched on the basis of emotions. In neither the labelling nor matching emotion conditions did the groups differ in their speed of emotion processing. Findings of the present study extend reports of ‘emotional dampening’ to hypertensives as well as to those at-risk for developing hypertension (i.e. prehypertensives) and have important implications for understanding the psychological component of such medical conditions as hypertension.     

Behavioral predictors of blood pressure variation in hypertensives and normotensives

This study examined the relative impact of five behavioral factors--activity, posture, location, social involvement, and tension--on the 24-hr blood pressure (BP) variability of 21 normotensives, 18 borderline hypertensives, and 18 sustained essential hypertensives. Multiple-regression analyses indicated that within each diagnostic group, activity accounted for more variance in BP variability than any other behavioral dimension. For each behavioral dimension examined, the magnitude of the relationship with BP was generally greater for the normotensives than for both hypertensive groups. In contrast, variation due to individuals was a better predictor of BP variability for the two hypertensive groups than for the normotensive group. Number of months hypertensive and use of antihypertensive medication were related to BP variability for the sustained hypertensive group. Findings have implications for the use of ambulatory BP monitors and interpretation of resulting data.     

Effect of Transcendental Meditation versus resting on physiological and subjective arousal

On four successive days, 10 highly trained and experienced meditators were asked to relax for 5 minutes, meditate for 20 minutes, and then relax for 5 minutes. In contrast, 10 other subjects who had no training or experience with meditation were asked to relax for 5 minutes, rest for 20 minutes, and then relax for 5 minutes. Physiological arousal (heart rate, skin resistance, respiration rate, systolic blood pressure, diastolic blood pressure) and subjective arousal (cognitive, somatic, relaxation) were measured throughout the experiment. Results indicated that (a) prior to meditating or resting, meditators tended to have higher heart rates and diastolic blood pressure than did nonmeditators, (b) meditation was associated with generally reduced arousal, but (c) while meditating, meditators did not evidence lower levels of arousal than nonmeditators did while resting. This investigation employed controls, which were not used in previous investigations, and the results place qualifications on previously reported results. The results have implications for the study of personality functioning, stress management, and psychotherapy.     

The effects of progressive relaxation on stress and diabetic control

Four insulin-requiring diabetic Ss were followed in single-S designs to measure the impact of progressive muscle relaxation training on blood glucose and stress levels. Measures of blood glucose, stress, activity and caloric intake were taken four times a day, along with a daily measure of anxiety. Two of the 4 Ss showed a significant decrease in blood glucose during treatment periods as compared to baseline measures. Similarly, 2 of the 4 Ss showed a significant decrease in stress levels during treatment. A multiple regression analysis revealed some significant relationships between blood glucose, stress, activity level and caloric intake. The results support previous studies that show relaxation techniques to be a viable aid in establishing greater diabetic control.     

Blood pressure reactivity to active and passive behavioral conditions in hypertensives and normotensives

Blood pressure reactivity and passive behavioral tasks was studied in patients with mild essential hypertension and normotensive controls. The passive condition included 10 presentations of a 6 sec, 78 dB, 1000 Hz tone without any response requirements. In the active condition subjects were given an additional 10 tone presentations and asked to press a push-button at tone termination. The absolute and percent increase in systolic blood pressure from rest was greater in hypertensives than normotensives in response to the active condition but similar to the passive condition. It is concluded that patients with hypertension compared to normotensive controls show exaggerated blood pressure reactivity to tasks involving active but not passive coping efforts. Since the tasks used to induce active and passive coping in the present study were identical apart from coping requirements, the notion that the activity dimension in and of itself modulates reactivity differences between patients and controls is supported.     

Mothers' responses to the cries of normal and premature infants as a function of the birth status of their own child

Mothers of premature and full-term infants viewed and heard videotapes of premature and full-term infants. The onset of crying by both infants elicited physiological arousal (evident in blood pressure, skin conductance, and heart rate increases) in the adults. The mothers of premature infants responded with especially marked arousal to the infants' cries. These mothers also reported that they were more attentive and alert while the infant was crying. The subjects responded similarly to the cries of full-term and premature infants. Mothers who described their own baby as easy exhibited a lower increase in diastolic blood pressure and heart rate, and reported being more alert, attentive, and willing to interact with the stimulus babies than those whose own baby appeared “difficult.”     

Blood pressure estimation and beliefs among normotensives and hypertensives

Although health professionals believe that blood pressure (BP) is asymptomatic, most diagnosed hypertensives are confident that they experience specific symptoms and emotions that help them detect their BP levels. Several months after screening interviews that elicited subjects' BP beliefs, 14 medicated hypertensives, 15 nonmedicated mild hypertensives (diastolic BP greater than or equal to 90 mm Hg), 39 normotensives, and 13 hypotensives (systolic BP less than or equal to 100 mm Hg) participated in a 1- to 2-hr laboratory experiment that assessed each subject's symptoms, moods, and estimates of systolic BP (SBP) relative to actual SBP levels. Several self-reports and autonomic measures were collected 45 times during and after each of 22 tasks. Subjects never received SBP feedback during the experiment. Within-subject correlations indicated that all subject groups could estimate SBP at levels greater than chance (mean estimated SBP-actual SBP correlation = .25). Further, 68% of the subjects evidenced at least one significant symptom-SBP correlation. Although medicated hypertensives believed they could estimate their BP more accurately than other groups by using their symptoms and emotions, they were actually no more accurate than the other groups. They also evidenced far fewer empirically derived symptom-SBP and emotion-SBP correlations than any other group. Overall, BP beliefs were largely inaccurate. If these erroneous beliefs can be eliminated, subjects may be able to estimate BP fluctuations more accurately.     

Does anxiety or cardiovascular reactivity have a causal role in hypertension?

Anxiety, stress, and cardiovascular reactivity (CVR) are variously believed to play a role in sustained hypertension. Although acute anxiety or stress elicits acute pressor responses, there is little support for their significant role in sustained hypertension. Anxiety correlates poorly with CVR, and blood pressure levels and anxiolytics do not sustain blood pressure lowering in subjects with hypertension-associated anxiety. Chronic anxiety disorders tend to be characterized by relatively low blood pressure and prevalence of sustained hypertension. Blood Pressure Regulation in hypertension is normal, and normo- and hypertensives have similar ambulatory blood pressure variability. Laboratory CVR fails to predict variability in natural environments, hyperreactors do not exhibit increased variability in natural environments, and the increased variability and ambulatory reactivity that is "accounted for" by laboratory responses is small. These findings do not support the belief that hypertension is related to a summation of heightened pressor responses over time. Antihypertensives normalize elevated blood pressures but do not alter CVR in the laboratory or variability in natural environments, probably because of a dual central regulation of resting and reactive blood pressures. Psychological stress responses result from selective neuronal activation rather than from generalized sympathetic neural responses or dysregulation. Differences in blood pressure responses during various emotions are only quantitative, with no specificity of sympathoadrenal or emotional responses to stressors. It may be time to regard reactive cardiovascular responses as physiological, rather than as psychological, and to require much stronger evidence to confirm causal roles of anxiety, stress, and reactivity in sustained hypertension.     

Psychophysiological reactivity to mental arithmetic stress in black and white normotensive men

Racial differences in physiological responses to a behavioral stressor were examined. Thirty-four Black and 42 White male normotensives 34 to 55 years old (mean age = 43.01 years) performed a mental arithmetic task while blood pressure, heart rate, and skin conductance were recorded. Compared to Whites, Blacks had significantly higher baseline diastolic blood pressure (77.93 mm Hg vs. 73.11 mm Hg) and lower skin conductance levels (11.08 microS vs. 12.25 microS). These effects persisted during performance of the mental arithmetic task. However, when baseline differences were covaried, there were no significant physiological effects associated with the task. Analysis of changes in response levels from baseline revealed a nonsignificant trend for Whites to show greater increases in systolic blood pressure than Blacks. There were no significant race or family history effects. Further, task performance did not influence the outcome. Failure to demonstrate greater cardiovascular reactivity in Blacks and all men with a positive family history of hypertension is discussed with regard to possible "survivor effects" and methodologic limitations.     

Self-control progressive relaxation training as an alternative nonpharmacological treatment for essential hypertension: therapeutic effects in the natural environment.

Two clients with 3 and 5$\text{1}\text{2}$ yr history of essential hypertension were successfully treated using self-control progressive relaxation training (PRT). Blood pressure was self-recorded twice daily in the natural environment by each client. The natural environment blood pressures of both clients declined during treatment and stabilized within the normotensive range. Blood pressure reductions were maintained at six months follow-up for one client and two months for the other.     

Information Load Stress,Risk Taking,and Physiological Responsivity in a Visual-Motor Task1

The effects of four levels of information load on performance, risk taking, and physiological responsivity (blood pressure and heart rate) are investigated. Twenty-five adults participated in a handeye coordination task, presented as a video game. Increases in load resulted in performance decrements and increased proclivity to take risks. Participation in the task increased (diastolic) arousal. Load effects on arousal were negligible. Subjects with greater diastolic blood pressure elevations engaged in more risk taking. The potential of two separate groupings of stressor effects, directly producing cognitive performance changes in one case and producing affective/arousal impacts in the other case (with potential indirect effects on cognition and performance), is considered. Suggestions for future research are made.     

An examination of methods for producing relaxation during short-term laboratory sessions

Reductions in psychological and physiological correlates of tension produced by various muscle relaxation training techniques were examined during a short-term laboratory session. Two studies are described involving a combined total of one hundred subjects receiving either abbreviated progressive relaxation, visual, auditory, or tactile electromyographic (EMG) biofeedback procedures. The Anxiety Differential was administered before and after the laboratory session. Heart rate, respiratory rate, skin conductance, systolic blood pressure, and frontalis and dominant forearm extensor EMG measures were obtained before, during, and after administration of relaxation training. Results indicated feedback in the tactile modality to produce overall reductions in tension comparable to those produced by progressive relaxation. Overall reductions in tension displayed by both progressive relaxation and tactile feedback were generally greater than reductions shown by visual or auditory feedback procedures. Interpretations suggest that certain forms of EMG feedback may offer an alternative to progressive relaxation techniques for producing short-term reductions in tension. Feedback modality is further indicated as a potentially important variable during relaxation training using the EMG feedback technique.     

Effect of Relaxation Therapy in Reducing Blood Pressure of Essential Hypertension Patients

The study investigated the effect of relaxation therapy on arterial blood pressure of Patients with essential hypertension. Ten known essential hypertension patients (males = 3; females = 7, age range 41–70, mean age 57.2 years, SD = 9.93 years) were sampled randomly from Medical outpatient department of the State owned University teaching Hospital in Ebonyi State South East, Nigeria. These Participants were exposed to 30 minutes relaxation therapy and their blood pressures were taken before and after the treatment. Using matched t test to compare baseline and post treatment scores, result showed that relaxation therapy progressively decreased both diastolic and systolic blood pressure readings of the Participants. The study concluded that Relaxation therapy can transiently lower the systolic and diastolic blood pressure.     

Effects of massed practice and cue-controlled relaxation on tic frequency in Gilles de la Tourette's syndrome

The effects of massed practice (MP) and cue-controlled relaxation on tic frequency were assessed in three single-case studies. Measures of tic frequency, subjective tension and fatigue, and physiological arousal were obtained throughout treatment.MP failed to produce any reduction in tic frequency in the three Gilles de la Tourette's syndrome patients studied. Cue-controlled relaxation resulted in a moderate decrease in tic frequency in only one patient.Tic frequency was related to physiological arousal, as assessed by skin conductance response frequency. No evidence was obtained in support of the suggestion that ticquers demonstrate a deficit in their habituation to sensory stimulation.     

Source of arousal and memory for detail

Two questions about the relationship between arousal and memory were investigated: First, does the source of arousal influence memory, and, second, what impact does arousal have on memory for detail? In Experiment 1, physiological arousal (running or not running in place) was factorially combined with emotional arousal (viewing a neutral or an emotional slide sequence). Recognition memory was tested for gist, central detail, and background detail. Experiments 2 and 3 were similar to Experiment 1, with the exception that a cued recall task was used in Experiment 2 and physiological arousal was manipulated with stationary biking in Experiment 3. The results of these experiments indicated that physiological arousal had little impact on memory and that emotional arousal led to improvements in memory for both central and background detail. Overall, these results supported the notions that the source of arousal is an important determinant of an event’s memorability (Christianson, 1992a) and that emotional arousal serves to enhance the scope of memory (i.e., flashbulb memory; Brown &; Kulik, 1977).     

Critical procedural variables related to the physiological effects of progressive relaxation: a review.

Twenty-five investigations of the physiological effects of progressive relaxation training were classified according to whether relaxation was found to be superior or equivalent to control conditions. The two sets of studies differed significantly on number of training sessions and in the use of taped vs live administration of training, and they tended to differ in the use of normal vs patient samples. The likelihood of producing significant physiological reductions via progressive relaxation appears to be greater when multi-session, subject-controlled training is conducted with subjects for whom physiological activity contributes to a presenting. clinical problem.     

Personal space invasions in the lavatory: suggestive evidence for arousal.

The hypothesis that personal space invasions produce arousal was investigated in a field experiment. A men's lavatory provided a setting where norms for privacy were salient, where personal space invasions could occur in the case of men urinating, where the opportunity for compensatory responses to invasion were minimal, and where proximity-induced arousal could be measured. Research on micturation indicates that social stressors inhibit relaxation of the external urethral sphincter, which would delay the onset of micturation, and that they increase intravesical pressure, which would shorten the duration of micturation once begun. Sixty lavatory users were randomly assigned to one of three levels of interpersonal distance and their micturation times were recorded. In a three-urinal lavatory, a confederate stood immediately adjacent to a subject, one urinal removed, or was absent. Paralleling the results of a correlational pilot study, close interpersonal distances increased the delay of onset and decreased the persistence of micturation. These findings provide objective evidence that personal space invasions produce physiological changes associated with arousal.