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B T Engel

Publications and source records attributed to B T Engel.

120 records · Page 7Linked to original sources

Autonomic behavior.

This article summarizes a body of work which collectively shows that autonomic responses meet the criteria for behavior. They can be modified reliably through the systematic use of antecedent (cues) and consequent (contingencies) stimuli. This means that autonomic responses, which are usually characterized as elicited reflexes, can be learned responses (viz., behaviors). This review cites a number of experimental and clinical studies in which autonomic learning has been shown to occur and to have clinical importance. Of special interest to gerontologists are the clinical studies which show that incontinent and hypertensive elderly patients can be trained to normalize their pathognomic responses.

Aged↗

Nonshivering thermogenesis during acute cold exposure in adult and aged C57BL/6J mice.

In C57BL/6J adult and aged mice, housed at room temperature (22.5 +/- 1 degrees C), we measured O2 consumption and CO2 production and calculated metabolic heat production under conditions of anesthesia and myorelaxation during acute cold stimulation when body temperature was lowered 7.5 degrees C below control level. An independent group of mice was subjected to a three hour partial physical restraint at 6 degrees C and concentration of uncoupling protein (thermogenin) was measured in interscapular brown adipose tissue mitochondria at different times after cold exposure. Heat production under anesthesia and myorelaxation was about 57-66% lower than in nonanesthetized conditions, but increased significantly during cold stimulation in both age groups. Under anesthesia and myorelaxation before and during cold stimulation aged mice produced about 20% more heat than adult mice. Because in these experiments all sources of facultative thermogenesis, except nonshivering, were suppressed by anesthesia and myorelaxation, and because brown adipose tissue is the major source of nonshivering thermoproduction, we concluded that aged mice housed at room temperature have an increased thermogenesis in brown adipose tissue. This conclusion was also supported by the finding that the concentration of uncoupling protein measured in the mitochondria of brown adipose tissue after single cold exposure was significantly higher in aged than in adult mice. Therefore, we propose that the lower, cold-induced, heat production typically observed in nonanesthetized aged mice may reflect reduced thermogenic capacity of skeletal muscles. While aged mice have less brown adipose tissue than adult animals, the remaining brown adipose tissue may compensate by increasing the concentration of uncoupling protein.

Adipose Tissue, Brown↗

Heat loss during cold exposure in adult and aged C57BL/6J mice.

Metabolic heat production (MHP), colonic temperature (Tco), and nonevaporative (dry) heat loss were measured in ADULT and AGED C57BL/6J male mice during cold exposure. Dry heat loss was assessed as a differential temperature (Td) between incoming and outgoing air through the chamber for indirect calorimetry. The average Td during cold exposure normalized to surface area for ADULT mice was significantly higher than that for the AGED animals (0.0618 +/- 0.0003 degree C/cm2 and 0.0553 +/- 0.0005 degree C/cm2, respectively). Linear regression analysis showed that at the same Tco AGED mice showed lower values of Td normalized to surface area, indicating that at the same body temperature they were losing less heat than ADULT animals. It was concluded that age-related decline in cold tolerance in mice is not due to a lack of ability to reduce heat loss during cold exposure. On the contrary, AGED animals had lower heat loss in comparison with ADULT. We suggest that augmentation of heat conservation mechanisms is an adaptive response to diminishing cold-induced heat production.

Aging↗

A behavioral analysis of chest pain in patients suspected of having coronary artery disease.

A group of 83 men and women who had been referred to Johns Hopkins Hospital for cardiac catheterization for evaluation of chest pain and possible coronary artery bypass surgery were assessed behaviorally for their chest pains. During the approximately 2-week period between clinical evaluation and catheterization, the patients completed self-report forms about their chest pains. Patients completed one form for each episode of chest pain. Referring physicians also completed a form about the patients "typical" chest pain. The data were analyzed in terms of the antecedents, concomitants, and consequences of the chest pain, and patients' reports were compared to physicians' judgments. Major findings were as follows: 1) Antecedents--most episodes occurred while the patient was at home at times when his mood was one of contentment. 2) Concomitants--the average patient reported fewer than one episode per day which persisted for about 4 min and was rated as 36 on a scale of 0 to 100. The most common physical symptoms accompanying the episode were breathlessness and weakness, and the most common pain sensations were reported to be pressing or aching. There was no consistency among patients either in primary location or path of radiation of the pain. Duration of pain did not correlate significantly either with sensation or symptoms; however, severity rating did correlate with symptoms and sensations. 3) Consequences--most episodes were self-treated with nitroglycerin or rest. Patients typically returned to their ongoing activities; however, there were a number of interactions between the likelihood of returning to ones ongoing activity and the antecedents of the episodes. 4) The referring physicians significantly overestimated the frequency and severity of their patients' episodes; furthermore, they were selective in their abilities to identify correctly the antecedents or concomitants associated with their patients' pain--e.g., they were reliable in their judgments about subjects who had sleep-related episodes; however, they were inaccurate in characterizing the typical sensations or symptoms reported by their patients. It is suggested that a behavioral analysis may enable a physician to characterize his patient's chest complaints better, and perhaps also may facilitate the differentiation between chest complaints indicative of coronary artery disease and chest complaints of a noncoronary origin.

Coronary Disease↗

The relation of chest pain symptoms to angiographic findings of coronary artery stenosis and neuroticism.

The present article examines the relations among self-reported and physician-estimated chest pain variables to angiographically determined coronary stenosis (CAD) and neuroticism scores. Six of the 48 chest pain variables were significantly related to coronary stenosis, but only one variable, chest pain elicited by walking, was positively related to stenosis. Chest pain during sleep, sighing and dizziness accompanying chest pain, right lower chest pain radiation, and infrequent rest to cope with the chest pain were significantly negatively related to stenosis. Neuroticism scores (N) were not significantly related to CAD but were significantly correlated with 13 of the 48 chest pain variables. In addition to correlating positively with the chest pain variables that were negatively correlated with CAD, N scores were significantly related to higher pain severity ratings, being angry, annoyed, tense, afraid, worried, and upset before the chest pain, breathlessness during the pain episode, and pain sensations described as stabbing. The six chest pain variables significantly correlated with CAD yielded a multiple correlation of 0.58, accounting for 34% of the variance, whereas N scores accounted for only 5% of the variance; however, N contributed less than 1% unique variation to stenosis in combination with the six chest-pain variables. That N influences chest pain reports more than actual stenosis is further confirmed by the results of physicians' ratings of their patients' typical chest pain episodes. Recognition of patients' characteristic levels of distress or neuroticism may aid physicians in evaluating symptoms more accurately and in treating their chest pains more appropriately.

Age Factors↗

Psychosomatic medicine, behavioral medicine, just plain medicine.

Neurally mediated physiologic responses fulfill all of the criteria for behavior and obey all of the laws of behavior subject to the anatomic and physiologic constraints inherent in their structures and functions. It is illogical and wrong to assert that neurally mediated responses interact with behavior. THEY ARE BEHAVIOR. These principles are a legitimate and necessary part of the training of all medical students, residents, and fellows. The conceptual basis of psychosomatic practice does not need to be derived from the dualistic notions of psychoanalysis or from the dualistic notions of biobehaviorism. Psychosomatic medicine is an integral aspect of medical practice. It needs to exist because people act and react differently from one another, and because the same person acts and reacts differently from one situation to another. Psychosomatic medicine is not psychiatry in medicine. Each of the specialties and each of the subspecialties encounters its own set of psychosomatic problems; and treatment strategies to resolve these problems need to be integrated into the clinical practice of that discipline.

Behavior↗

A controlled study of a standardized behavioral stepped treatment for hypertension.

A standardized behavioral stepped care (SC) treatment for hypertension (blood pressure monitoring followed by self-administered systolic blood pressure biofeedback and relaxation, in sequence, as needed) was administered to 51 patients whose blood pressures were medically controlled to within normal limits. The effects of treatment upon blood pressure, medication requirements, and cost of care were compared with those of 51 referred care (RC) control patients who continued their usual care for hypertension. SC and RC patients were matched in groups on the basis of medication requirements (Group I, diuretics; Group II, beta-blockers alone or with a diuretic; and Group III, vasodilators alone or with a drug from Group I or II). The duration of the SC procedure was 1, 4, or 7 months--as necessary--and the follow-up period was 12 months. The RC protocol lasted 19 months. Medication requirements for SC patients declined to levels significantly (p less than 0.05) lower than those of RC patients from the biofeedback phase throughout follow-up for all drug groups combined. However, when the drug groups were analyzed separately, this was true for Groups I and II only. Similarly, the cost of care for all drug groups combined was lower for SC patients from the biofeedback phase through 9 months of follow-up, also reflecting changes seen in Drug Groups I and II only. Blood pressure levels remained controlled, in all groups, throughout the investigation. Clinical possibilities for combined behavioral and pharmacological treatment of hypertension are discussed relative to the pathophysiology of hypertension, and questions for future research are suggested.

Antihypertensive Agents↗

An historical and critical review of the articles on blood pressure published in Psychosomatic Medicine between 1939 and 1997.

Between 1939 and 1997, there have been 59 volumes of Psychosomatic Medicine. Over this period there were 200 articles dealing with blood pressure. About 90% of these were concerned with high blood pressure. This article reviews all of these papers both from an historical perspective and critically. Although there has been a significant growth in the rate of articles published since 1939, there has always been a strong interest in the nature of hypertension, particularly the roles of affects and emotions in the natural history of the disease. For example, volume 1, number 1 of the Journal includes a symposium on high blood pressure in which Franz Alexander stated his well-known hypothesis that the chronic inhibition of rage plays a causal role in the production of hypertension. In various forms, the notion that anger is an important mediator of hypertension has neither been proved nor abandoned. One major conclusion drawn from this review is that the current research on high blood pressure is drifting somewhat aimlessly. It has become preoccupied with demonstrations that various stimuli or situations (usually characterized as stresses) can acutely raise blood pressure. Despite this focus, neither the necessary nor the sufficient conditions for labeling a stimulus as stress has ever been agreed upon. Likewise, there have been many demonstrations of an iatrogenic effect on blood pressure, but neither the behavioral mechanisms underlying this effect nor the strategies for eliminating it have been explicated. Finally, this article identifies several areas where it would be useful to review and integrate current knowledge. Hopefully, such integrations could play a significant role in focusing and shaping future research and clinical practice.

Blood Pressure↗