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.

A plethysmographic method for demonstrating the response specificity of the oral vascular bed.

In this paper, we describe a new method for measuring the oral plethysmogram, and we assess its sensitivity and specificity under differing psychological stimulation. Finger and palate pulse amplitudes and blood pressure were monitored while individuals (N = 13) performed several tasks: mental arithmetic, nausea imagery, fear imagery, and anger imagery. Pulse pressure, having a major effect on pulse amplitude, was partialed out in analyses. Palate pulse amplitude increased significantly in response to the degree to which the individual felt irritated, judged, nauseated, or angry. In contrast, finger pulse amplitude changed significantly only in the arithmetic task and, unlike the palate, showed a decreased amplitude with increased irritation and being judged. Results indicate that the oral plethysmogram can serve as a reliable measure of oral mucosal vasomotor reactivity and that it has a different pattern of response specificity than does the finger.

Relationship of expressed anger to forearm muscle vascular resistance.

The relationship of style of anger expression to physiological reactivity was examined in 45 nonmedicated subjects during their performance of three tasks with contrasting response demands. The primary physiological focus was on forearm muscle vascular resistance (FMVR) with forearm muscle blood flow (FMBF), digital pulse volume (DPV), digital vascular resistance (DVR), heart rate (HR), diastolic blood pressure (DBP), systolic blood pressure (SBP), and electrodermal frequency (EF) monitored. Family Expressed Anger, i.e. the overtness of anger expression in the subject's family of origin, was related to FMVR such that the more anger was expressed in the family of origin, the greater the vasoconstriction during Mental Arithmetic and the less the vasoconstriction during Anger Imagery. Self Expressed Anger, i.e. the degree to which others were aware when the subject was feeling angry, was related to SBP and DBP during Vigilance with a lesser degree of anger expression going with greater blood pressure increases. The meaning of these findings in relation to task appraisal and task demand is discussed.