Biomedical subjects

S Hochron

Publications and source records attributed to S Hochron.

8 recordsLinked to original sources

PubMed1997

Defensiveness and perception of external inspiratory resistive loads in asthma.

This study examined the relationship between defensiveness, as measured by the Marlowe-Crowne Social Desirability Scale (MCSDS), and the perception of an externally applied respiratory resistance among people with asthma. Thirty asthmatic adults breathed through nine levels of inspiratory resistive load. Participants higher on the MCSDS were less accurate than others in psychophysical magnitude estimates of resistive load, and showed a reduced relationship between the physical load and the quality of respiratory sensations associated with exposure to the resistors. Defensive subjects also showed a differentially high increase in correlation between unpleasantness of respiratory sensations and resistance levels after receiving parenteral naloxone. These findings are consistent with the hypothesis that defensiveness may increase risk of asthma morbidity, due to inaccuracy in detecting sensations of dyspnea during asthma exacerbations. The inaccuracy may be caused by elevated endogenous opioids among defensive individuals.

Adult↗

PubMed1997

Respiratory sinus arrhythmia versus neck/trapezius EMG and incentive inspirometry biofeedback for asthma: a pilot study.

This pilot study compared biofeedback to increase respiratory sinus arrhythmia (RSA) with EMG and incentive inspirometry biofeedback in asthmatic adults. A three-group design (Waiting List Control n = 5, RSA biofeedback n = 6, and EMG biofeedback n = 6) was used. Six sessions of training were given in each of the biofeedback groups. In each of three testing sessions, five min. of respiratory resistance and EKG were obtained before and after a 20-min biofeedback session. Additional five-min epochs of data were collected at the beginning and end of the biofeedback period (or, in the control group, self-relaxation). Decreases in respiratory impedance occurred only in the RSA biofeedback group. Traub-Hering-Mayer (THM) waves (.03-.12 Hz) in heart period increased significantly in amplitude during RSA biofeedback. Subjects did not report significantly more relaxation during EMG or RSA biofeedback than during the control condition. However, decreases in pulmonary impedance, across groups, were associated with increases in relaxation. The results are consistent with Vaschillo's theory that RSA biofeedback exercises homeostatic autonomic reflex mechanisms through increasing the amplitude of cardiac oscillations. However, deep breathing during RSA biofeedback is a possible alternate explanation.

Adolescent↗

PubMed1997

The effect of facial and trapezius muscle tension on respiratory impedance in asthma.

This study tested two theories about the relationship between voluntary changes in muscle tension and pulmonary function in asthma. Kotses has theorized that decreased facial muscle tension decreases respiratory impedance via a hypothesized vagaltrigeminal reflex, but that muscle tension in other muscle groups has no such effect. Others have suggested that decreased thoracic muscle tension improves pulmonary function. Subjects were 19 volunteer asthmatic adults. They performed 3-minute cycles of deliberate muscle contraction, alternating two each for the shoulder and forehead muscles, followed by dominant forearm contraction. Surface EMG was measured from the frontalis and right trapezius areas. Airway impedance was measured by forced oscillation pneumography. Cardiac interbeat interval and respiratory sinus arrhythmia were measured to assess vagal tone. Frequency dependence of respiratory impedance increased during shoulder tension, giving some support to the theory relating thoracic tension to impairment in pulmonary function. Correlational analyses suggested a negative relationship between changes in cardiac interbeat interval and both frontalis muscle tension and decreased compliance of tissues in the airways. These findings are the opposite of those predicted by the vagal-trigeminal reflex theory.

Adolescent↗

PubMed1992

The effects of suggestion on airways of asthmatic subjects breathing room air as a suggested bronchoconstrictor and bronchodilator.

Thirty-three asthmatic subjects were told they were receiving, alternately, an inhaled bronchoconstrictor and inhaled bronchodilator, although they actually were only breathing room air. No subjects showed suggestion-produced effects on FEV1, although two (of the 19 on whom FEF50 was measured) showed effects of greater than 20% on measures of maximal midexpiratory flow. The incidence of the effect is smaller than reported previously, possibly because some subjects in previous studies inhaled saline, a mild bronchoconstrictor, and reversal of effect was not required for classification as a reactor. Higher percentages of subjects in this study showed decreased MMEF in response to the 'bronchoconstrictor', but this appeared to reflect fatigue rather than suggestion effects. However, the fact that the effect occurred in a relatively non-effort-dependent measure suggests that real changes occurred in bronchial caliber, not just in test effort. Suggestion had a significant effect on perception of bronchial changes, but the correlation between actual and perceived changes was minimal. There was an increase in FVC prior to administration of the 'bronchoconstrictor', possibly reflecting a preparatory response to the expected drug. Correlations among self-report variables suggested the existence of three personality dimensions among our population related to suggestion and asthma: cognitive susceptibility to suggestion of bronchial change; feeling of physical vulnerability; and anxiety. However, there was no significant relationship between airway response to suggested changes and hypnotic susceptibility, as measured by the Harvard Group Scale of Hypnotic Susceptibility.

Airway Resistance↗

PubMed1992

Psychological approaches to the treatment of asthma.

Outcome literature on psychological treatment for asthma covers psychoeducational self-management programs, relaxation therapy, biofeedback, and family therapy. Psychoeducational approaches now being standardized in a national program are cost-effective. They produce improved adjustment, increased medication compliance, greater perceived self-competence in managing symptoms, and decreased use of medical services. Significant effects have been found for relaxation therapy, although it is not clear whether the effectiveness depends on whole-body relaxation or specifically facial- or respiratory-muscle relaxation. Family therapy is helpful to some asthmatics. Active components in these methods remain to be identified as do the populations whom they can best serve. Biofeedback for respiratory resistance, trachea sounds, and vagal tone shows promise but has not been given adequate clinical testing.

Asthma↗

PubMed1989

Hypnotic susceptibility and its relationship to outcome in the behavioral treatment of asthma: some preliminary data.

12 subjects from an experiment on relaxation therapy for asthma were given the Harvard Group Scale of Hypnotic Susceptibility, Form A. Full scale hypnotic susceptibility scores were positively correlated, at a borderline significance, with improvement in the methacholine challenge test, a measure of asthma severity. Performance on the amnesia item of the Harvard Group Scale was correlated with improvement in self-reported symptoms of asthma.

Adult↗

PubMedDate not supplied

The effects of suggestion and emotional arousal on pulmonary function in asthma: a review and a hypothesis regarding vagal mediation.

This paper reviews the empirical literature on the relation between asthma, suggestion, and emotion, and proposes the hypothesis that these effects are mediated parasympathetically. The literature indicates that, among asthmatics, suggestion can produce both bronchoconstriction and bronchodilation, and that stress can produce bronchoconstriction. The proportion of asthmatic subjects showing bronchoconstriction to both suggestion and stress averages 35%-40% across studies, but, because of methodological considerations, might be conservatively estimated as closer to 20%. The effect is smaller for suggestion of bronchodilation, and is very short-lived among nonasthmatics. No clear connection has been found between these responses and such subject variables as age, gender, asthma severity, atopy, or method of pulmonary assessment, although some nonsignificant tendencies appear. Most studies in this literature used small n's and did not systematically examine various somatic, environmental, and demographic factors that could influence results. A hypothesis is presented regarding vagal mediation of psychological effects on the airways, as well as possible alternative mechanisms, and recommendations for future research to evaluate these hypotheses.

Airway Obstruction↗

PubMedDate not supplied

Behavioral task-induced bronchodilation in asthma during active and passive tasks: a possible cholinergic link to psychologically induced airway changes.

This study investigated pulmonary and autonomic reactions to active and passive behavioral laboratory tasks among asthmatic subjects. It also examined the relationship between airway irritability, as measured by the methacholine challenge test (MCT), and autonomic activity and reactivity to these tasks. Fifty-one asthmatic and 37 nonasthmatic subjects were exposed to psychological laboratory tasks involving either active (mental arithmetic and reaction time) or passive (films depicting shop accidents and thoracic surgery) response. The MCT was given to asthmatics in a separate session. Active tasks reduced respiratory impedance, as measured by forced oscillation pneumography. They also increased heart rate and appeared to block vagal activity, as measured by respiratory sinus arrhythmia (RSA). Airway irritability as assessed by the MCT was positively related to amplitude of RSA and to skin conductance levels. Our data suggest that active and passive behavioral tasks may produce different pulmonary effects among both asthmatic and nonasthmatic individuals. Engaging in tasks requiring active responses may produce temporary improvements in pulmonary function. No autonomic differences were obtained between asthmatics and nonasthmatics in physiological response to stress, but greater cholinergic receptor sensitivity was suggested among high responders to methacholine.

Adolescent↗