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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.

Changes in body image across the menstrual cycle and the relationship between these changes and menstrual distress were investigated in an effort to identify determinants of body dissatisfaction. Twenty-six normally cycling women between 18-40 years of age and 90-115% of ideal body weight, with no history of an eating disorder, completed a series of body image measures and a measure of menstrual distress during three menstrual cycle phases: perimenstrual, follicular, and luteal. These phases were identified with serum levels of ovarian hormones and basal body temperature. Results indicated that body dissatisfaction as measured by the number of body-related negative thoughts and anxiety about appearance was significantly highest during the perimenstrual phase. In contrast, measures of body size perception remained stable. Several somatosensory and psychological symptoms of menstrual distress were significantly associated with body dissatisfaction during the perimenstrual phase including, water retention, autonomic reactivity, control, negative affect, and impaired concentration. This association of body dissatisfaction and menstrual distress strongly suggests that menstrual cycle changes play a significant role in body image.

Proposed binge eating disorder (BED) diagnostic criteria were investigated to provide necessary psychometric characteristics and explore their utility in assessment. One hundred four subjects (52 self-referred bingers, 52 comparison subjects) completed an initial administration of the Questionnaire of Eating and Weight Patterns (QEWP). The results supported the ability of the two core BED criteria (i.e., episodic overeating, loss of control) to discriminate between clinical and nonclinical binge eaters. Thirty-nine of the self-referred and 40 of the comparison subjects completed a second QEWP administration 3 weeks later. Results indicated that the BED diagnosis was moderately stable over the 3-week interval (kappa = .58, combined sample). Using self-monitoring data completed by the self-referred subjects, predictive efficiency analyses indicated that the QEWP was able to identify both high and low probability binge eaters. Implications of the findings for the definition, assessment, and utility of the BED diagnosis are discussed.

We discuss the use of synchronous-demodulation (lock-in) techniques for evoked potential retrieval. Application to electronically swept visual displays is emphasized. These techniques permit a visual threshold to be specified in 20 s, but their application to visual assessment requires careful consideration of several problems, notably alleged delay in the instrumentation, specification of the baseline response level, and the nature of EEG interference. In addition, since stimulus waveform information is lost in all lock-in methods, questions concerning what activity is contributing to the measured response must be answered. A technique addressing these issues and combining phase-sensitive detection and vector computation is presented.

2. The improper integral defined as the limit of a sum. We first consider the case where ak = 1 (k =1, 2, 3, * * * ). A fundamental difficulty not encountered in the previous paper is apparent from the definition of .fof(x)dx. Bromwich and Hardy have considered this problem [2]. As they point out, the ordinary definition of this improper integral is by means of a double (repeated) limit; and in order to replace this limit by the single limit

NASA and the Max Planck Institute for Extraterrestrial Physics (MPE), Munich, Germany, conducted a cooperative experiment involving the release and study of a barium cloud at 31,500 km altitude near the equatorial plane. The release was made near local magnetic midnight on Sept. 21, 1971. The MPE-built spacecraft contained a canister of 16 kg of Ba CuO mixture, a two-axis magnetometer, and other payload instrumentation. The objectives of the experiment were to investigate the interaction of the ionized barium cloud with the ambient medium and to deduce the properties of electric fields in the proximity of the release. An overview of the project is given to briefly summarize the organization, responsibilities, objectives, instrumentation, and operational aspects of the project.

We discuss the use of synchronous-demodulation (lock-in) techniques for evoked potential retrieval. Application to electronically swept visual displays is emphasized. These techniques permit a visual threshold to be specified in 20 s, but their application to visual assessment requires careful consideration of several problems, notably alleged delay in the instrumentation, specification of the baseline response level, and the nature of EEG interference. In addition, since stimulus waveform information is lost in all lock-in methods, questions concerning what activity is contributing to the measured response must be answered. A technique addressing these issues and combining phase-sensitive detection and vector computation is presented.

Sudden, repetitive illumination of the dark-adapted monkey eye produces transient changes in the electroretinogram and transocular potential which can last an hour or longer.