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Biomedical subjects

D Shapiro

Publications and source records attributed to D Shapiro.

At least 253 records · Page 14Linked to original sources

Voluntary control of penile tumescence.

This study investigated the voluntary control of penile tumescence in the absence of external erotic stimulation. Twelve experimental subjects were given analogue visual feedback and monetary rewards for increase in penile diameter as measured by a strain gauge. Twelve control subjects were given no analogue feedback and noncontingent rewards but the same instructions to maximize erections. While both groups were capable of voluntary penile tumescence, significantly improved performance was observed in the experimental group. Two distinct psychophysiological patterns of voluntary penile tumescence were observed. A "tension" pattern was associated with marked heart rate acceleration, irregular respiration, and variable penile response. A "relaxation" pattern was associated with stable heart rate, regular respiration, and smooth tumescence curves. In using these procedures for the treatment of sexual dysfunctions, it is suggested that feedback and reward be given for a combined pattern of sexual and autonomic responses.

Autonomic Nervous System↗

Home relaxation techniques for essential hypertension.

A 10-week relaxation treatment focused on home practice and self-monitoring of blood pressure for the purpose of lowering blood pressure in patients with essential hypertension. Comparisons were made among relaxation (n = 13), relaxation in combination with electromyographic biofeedback (n = 14), and a control condition in which patients simply monitored their blood pressure (n = 14). These three groups of patients, all of which received antihypertensive medication, were compared with a fourth group that practiced relaxation without drug therapy (n = 17). Relaxation and relaxation/biofeedback were equally effective in reducing blood pressure recorded at home in the morning and evening and produced greater decreases than in the control group. Relaxation without drugs, although somewhat more effective than self-monitoring, did not reduce blood pressure as much as the two conditions in which medication was combined with relaxation. Although reductions over the course of treatment were noted in blood pressure recorded in the laboratory, the four treatment conditions did not differ significantly from one another.

Adult↗

The effects of stress and caffeine on hypertensives.

Eighteen male hypertensives on diuretic medication between the ages of 37 and 60 were studied in a double-blind, randomized, crossover design under three conditions: 200 mg of caffeine and mental arithmetic; placebo and mental arithmetic; and 200 mg of caffeine alone. Systolic and diastolic blood pressure, heart rate, and skin conductance were recorded. During rest, caffeine compared to placebo increased blood pressure by 8/6 mm Hg, but had no effect on heart rate or skin conductance. During mental arithmetic, the combined effect of mental stress and caffeine led to a further increase of 17/7 mm Hg, reaching a pressure level of 163/100 mm Hg. Heart rate and skin conductance were increased above their prior caffeine levels. There were no significant differences between the blood pressure response to mental arithmetic with caffeine and that response to mental arithmetic with a placebo, which may have been due to the fact that the hypertensives were already responding at ceiling level during the mental stressor.

Adult↗

Caffeine, mental stress, and risk for hypertension: a cross-cultural replication.

Separate and combined effects of caffeine and mental arithmetic stress on systolic blood pressure (SBP) and heart rate (HR) were assessed in a double-blind, placebo-controlled study. Thirty-six Chinese nationals, half with and half without a family history of hypertension, received either 0, 125, or 250 mg of caffeine in three separate experimental sessions, each preceded by a 12-hour abstention from caffeine consumption. Caffeine and mental stress elevated SBP, but caffeine did not potentiate the SBP response to mental stress. Caffeine did not affect HR. A positive family history of hypertension was associated with larger SBP elevations to the higher dose of caffeine. Family history of hypertension was associated with larger blood pressure elevations during mental stress, but only under conditions of high-level stimulation provided by the initial exposure to the stress. These results support previous findings of greater cardiovascular reactivity to laboratory stress in individuals at high risk for hypertension.

Adult↗

Blood pressure response to the "second cup of coffee".

Twenty young male coffee-drinkers consumed 150 mg of caffeine in decaffeinated coffee three times a day for 8 days. On days 3, 4, 7, and 8, caffeine or a placebo was administered in the laboratory at 11 A.M., 8 A.M., 11 A.M., and 8 A.M., respectively, in a randomized double-blind crossover design. There was a blood pressure increase relative to the placebo 45 min after taking caffeine at 8 A.M. (5.8/6.5 mm Hg). An increase of 2.4/5.2 mm Hg was seen with the second cup of coffee at 11 A.M. The lower the subject's pre-coffee serum caffeine level, the higher the systolic response, both at 8 A.M. (r = -0.60) and at 11 A.M. (r = -0.62). Because of the pressor effect resulting from habitual caffeine intake, the adverse implications of caffeine use should be considered.

Adolescent↗

Ambulatory blood pressure and heart rate in paramedics: effects of cynical hostility and defensiveness.

Ambulatory blood pressure and heart rate responses were obtained in 33 male paramedics during a 24-hour work shift to examine the effects of episodes of occupational stress on cardiovascular reactivity and subjective reports of stress. The aim of this study was to determine how individual differences in cynical hostility and defensiveness interacted with situational demands to affect cardiovascular responses in a natural setting. Defensiveness was found to interact significantly with cynical hostility in predicting subjects' heart rate responses in different work contexts. Specifically, in a hospital setting involving interpersonal conflict, subjects who were high in both defensiveness and hostility showed heart rate responses approximately 10 bpm higher than subjects who were high in hostility but low in defensiveness. The same pattern of relationships was obtained for diastolic blood pressure. High and low hostile subjects were also found to differ from each other in their daily mean levels of ambulatory blood pressure during awake and sleep periods. These findings obtained in a natural setting lend further support to the significance of cynical hostility for cardiovascular reactivity. The results for defensiveness suggest the need for further research on the role of conflicting attitudes in the pathophysiology of cardiovascular diseases.

Adult↗

Hostility and differences between clinic, self-determined, and ambulatory blood pressure.

This study examined the role of personality factors in differences between three methods of assessing blood pressure (clinic, self, ambulatory) in 45 patients with mild hypertension. The data were obtained after the patients were withdrawn from antihypertensive medications and had achieved stable clinic diastolic blood pressure levels of 95 to 110 mm Hg, averaged over three visits in 2 to 4 weeks. Significant differences were obtained in systolic blood pressure (SBP) and diastolic blood pressure (DBP) as a function of method of assessment. These differences in both systolic blood pressure (SBP) and diastolic blood pressure (DBP) were associated with individual differences in the total score and several subscales of the Buss-Durkee Hostility Inventory (Assault, Resentment, Guilt), but not in anxiety, depression, or other characteristics. High hostile subjects had consistently high blood pressure values in both clinic, self, and ambulatory recordings. Low hostile subjects were significantly lower in self-recorded blood pressure readings taken at home and in ambulatory recordings, compared with clinic values. Implications of these findings for "white coat hypertension" are discussed.

Adult↗

Ambulatory stress psychophysiology: the study of "compensatory and defensive counterforces" and conflict in a natural setting.

Thirty years ago, Donald Oken raised basic questions about psychophysiological research strategies for the study of the "psychological stress response" in the laboratory. Is it possible to simulate in the laboratory the situations one normally encounters? Do laboratory stimuli provoke affective arousal? Are different classes of stress stimuli associated with specific physiological response patterns? How do one's characteristic "defenses" and coping styles modulate one's responses? This paper describes a novel ambulatory research strategy in which the laboratory is moved into the natural setting. The advantages of this strategy are exemplified in studies of paramedics in whom 24-hour recordings were made of ambulatory blood pressure and heart rate. The ambulatory physiological data were then related to information about specific work location and subjective ratings of stress made in a diary at the time of each reading, objective assessments of the different stressful situations encountered, and the role of individual differences in anger expression and defensiveness in modulating these relationships. The findings illustrate the ability of real-life stressors to bring out relationships not typically obtained in the laboratory. Moreover, the natural setting permits individuals to respond to behavioral challenges using their preferred mode of coping with stress, as opposed to the constraints imposed on them in the laboratory. This research strategy has also helped uncover the significance of conflict about the expression of hostility, rather than hostility per se, as a key factor in the "stress response."

Adaptation, Psychological↗

Immunological and physiological changes associated with induced positive and negative mood.

Functional and phenotypic immunological parameters were examined before, at the end of, and 20 minutes after the induction of positive and negative mood states, varied for arousal level, and a neutral state. The subjects were 14 male actors who experienced each condition on a different day. Compared with a neutral condition, all mood states affected several immune parameters (e.g., natural killer cell percentage and activity and percentage of suppressor/cytotoxic T cells), regardless of the valence or arousal level of the mood induced. The only immune variable differentially sensitive to positive and negative mood states was the proliferative response to the mitogen phytohemagglutinin; the response increased after positive moods and decreased after negative moods. Analysis of covariance for repeated measures indicated that heart rate, alone or in combination with physical activity and cortisol levels, had an impact on mood effects for most of the immune parameters investigated.

Adolescent↗

Effects of cynical hostility, anger out, anxiety, and defensiveness on ambulatory blood pressure in black and white college students.

This study asked whether individual differences in four personality traits (cynical hostility, anger out, anxiety, and defensiveness) would predict waking and sleeping ambulatory blood pressure and heart rate and whether information about these traits would provide a source of racial and gender differences in these measures. Ambulatory blood pressure and heart rate were recorded over a 24-hour period in 58 black and 86 white college students equally divided by gender. Waking and sleeping values were examined as a function of gender, race, and personality factors. Independent of personality factors, women had lower ambulatory blood pressure and higher heart rate than men, and black subjects had higher blood pressure levels and less of a decrease in heart rate from waking to sleeping than white subjects. The above differences were associated with personality factors. Black subjects scoring high on cynical hostility had elevated daytime and nighttime systolic pressure. Black subjects scoring high on both anxiety and defensiveness had higher waking diastolic blood pressure. Additional effects were shown for heart rate as a function of anger out, anxiety, and defensiveness. Given the special significance of ambulatory blood pressure for cardiovascular disease, these findings underscore the importance of personality factors for cardiovascular risk and their relevance for race and gender differences in this risk.

Adult↗

Smoking status and nicotine administration differentially modify hemodynamic stress reactivity in men and women.

OBJECTIVES: To investigate the impact of cigarette smoking and oral contraceptive (OC) use on hemodynamic stress responses of women. Also, to examine gender differences in stress reactivity as a function of smoking status and acute nicotine administration. METHODS: Thirty men and 46 women, differing in smoking status and OC use, were tested for cardiovascular stress responses to a variety of behavioral and physical stressors. Each was tested twice, once under a transdermal nicotine patch condition and once under a placebo patch condition. Impedance cardiography was used to estimate hemodynamic reactivity noninvasively. RESULTS: In response to behavioral stressors, women smokers, irrespective of OC use or nicotine vs placebo, demonstrated significantly blunted cardiac output and heart rate reactivity to stressors, and showed significantly greater estimated total peripheral resistance (TPR) under stress relative to women nonsmokers. There were no differences in hemodynamic stress reactivity between men smokers and nonsmokers. The only significant effect involving nicotine administration on stress reactivity was seen in men where, regardless of smoking status, nicotine increased heart rate reactivity to all stressors relative to placebo responses. CONCLUSIONS: Results suggest that cigarette smoking may act differently in men and women to increase risk for cardiovascular disease (CVD). For men, nicotine may exert pathogenic influences via increasing the magnitude of heart rate reactivity to stressors. For women, however, smoking seems to have deleterious effects on hemodynamic stress reactivity patterns, reducing myocardial but increasing TPR contributions to blood pressure responses.

Administration, Cutaneous↗

Ambulatory blood pressure, heart rate, and neuroendocrine responses in women nurses during work and off work days.

OBJECTIVE: This study examined women's cardiovascular and neuroendocrine responsiveness to work. METHODS: Ambulatory blood pressure (BP) and heart rate (HR) were recorded over 24-hour periods on 2 work and 2 off days during the luteal and follicular phases of the menstrual cycle in 138 registered nurses, aged 25 to 50 years. Urinary catecholamines and cortisol were measured for day and night periods. RESULTS: During waking hours systolic BP (SBP), HR, and epinephrine were higher on work than off days. Diastolic BP (DBP) and HR were highest at work. Nurses scoring high on job demands had elevations in daytime SBP, daytime HR only on work days, and nighttime epinephrine on work days. Compared with those with short work histories, nurses employed longer had consistently higher norepinephrine levels during days and nights, and higher nighttime DBP during off days. In unmarried nurses compared with married nurses, nighttime cortisol was lower during all 4 days and norepinephrine was lower during days off. All findings were independent of actigraph-recorded activity. CONCLUSIONS: Although the work environment leads to increased activity of the cardiovascular and sympathoadrenal medullary system in healthy women, the effects are modified by the woman's domestic role, by the length of her employment, and by the demands of her job.

Adaptation, Psychological↗

Beat-to-beat blood pressure response in asymptomatic IDDM subjects.

Nine insulin-dependent diabetic (IDDM) patients (aged 25-37 yr) with no symptoms of autonomic neuropathy and 15 healthy control subjects (aged 26-39 yr) were studied at rest and during tests of Valsalva maneuver, deep breathing, cold pressor, and postural change from sitting to standing. Continuous (beat-to-beat) measures were taken of heart rate, systolic blood pressure, diastolic blood pressure, and skin conductance. The diabetic patients were differentiated from the control group by the following: less variability in diastolic blood pressure during deep breathing, failure to exhibit diastolic blood pressure decreases during recovery from a cold pressor stimulus, a flatter blood pressure response pattern when changing from sitting to standing, and a smaller standing ratio (maximum/minimum) for R-R interval. Among the patients, age was negatively correlated with systolic and diastolic standing ratios and diastolic blood pressure variability during deep breathing. By use of the tracking cuff, a method of continuously recording blood pressure noninvasively, we have been able to assess subtle blood pressure changes, thereby revealing signs of sympathetic dysfunction in a group of relatively young diabetic patients with no symptoms of neuropathy. The tracking-cuff method of recording blood pressure has potential in further research on autonomic functioning in diabetic patients.

Adult↗