Systolic Blood Pressure and Heart Rate Changes During Three Sessions Involving Biofeedback or No Feedback

Two groups of normotensive human subjects of both sexes received contingent feedback for increases or decreases in systolic blood pressure, and two additional groups received random (non-contingent) feedback or no feedback. Subjects in all groups served fur three 1-hr sessions separated by intervals of 24 hrs. Reliable decreases in blood pressure, reaching a maximum of 9.5 mm Hg at the end of the third session, were observed in the decrease group. No systematic changes in blood pressure were observed in the increase, random, or no-feedback groups. Heart rate increased or decreased in the groups receiving contingent feedback for increasing or decreasing blood pressure, respectively. It is concluded that contingent feedback is effective in lowering blood pressure and that decreases are augmented by extended training. The covariance of heart rate and blood pressure is discussed with reference lo curlier experiments.     

The Acquisition of Autonomic Control Through Biofeedback: Some Tests of Discrimination Theory

Thirty-two subjects participated in 6 biofeedback training sessions to produce increases and decreases in skin conductance (SC) or heart rate (HR). Performance on control trials was examined with respect to SC and HR, as well as respiratory and somatomotor variables. The subjects also participated in 3 test sessions (on days 2, 5, and 9), which evaluated their ability to discriminate the target autonomic response, and sought to identify the bases for SC and HR discriminations. This design permitted examination of three major predictions from Brener's theory about the process which underlies the acquisition of autonomic control through biofeedback. The first prediction, that positive correlations should be obtained between control and discrimination performance throughout training, was not supported by the data. The other predictions, that control and discrimination performance both should become more specific to the target response as a function of training, were likewise not supported. On the whole, neither for SC nor for HR control was the pattern of results favorable to Brener's views.     

综合康复治疗对急性脑血管病肢体功能的影响

采用肌电生物反馈及经皮神经电刺激疗法，配合肢体被动功能训练，对６８例急性脑血管病者进行早期康复干预，采用Ｂｒｕｎｎｓｔｒｏｍ法，Ｌｅｖｅｅｔ肌力６级法，关节活动范围等进行肢体功能综合评定。结果发现患者肢体运动功能明显改善，总有效率分别为９０％和６１．１％，两者间有显著差异（Ｐ〈０．０１）。说明早期健康干预对急性脑血管病体肢运动功能的恢复有相当重要的作用，治病效果与治疗开始时间，治疗技术，病人的意识     

An Alpha Detection and Feedback Control System

A system of detecting EEG alpha rhythms and using these to control stimulus displays is described. The detection system parameters are chosen to match the psychological and behavioral processes with the EEG index in the time domain. The feedback control system is designed to control visual and auditory displays, clock and counters, and computer sampling routines, and provide maximum flexibility in experimental design.     

Stable T wave effects during improvement of heart rate control with biofeedback.

Under audiovisual heart rate feedback the differences between attempts to accelerate and decelerate improved with practice. Simultaneously, T wave amplitude was reduced during acceleratory trials and remained constant during deceleratory trials. The T wave difference between acceleratory and deceleratory trials, unlike the heart rate differences, did not improve with trial repetition. It was concluded that the improvement in heart rate control was parasympathetically mediated.     

肢体阻抗生物反馈仪的研制

本文介绍一种新型肢体阻抗生物反馈仪。该仪器应用四电极法从人体检测出肢体阻抗血流图，应用ＭＣＳ－５１单片机对每一个心动周期实时计算出变动阻抗峰峰值ΔＺｐｐ和心动周期时间Ｔ。用ΔＺｐｐ和Ｔ控制一组视觉和听觉反馈信号。     

Heart Rate Regulation With Success and Failure Signals

The purpose of this study was to examine the effects of success and failure signals on performance of subjects attempting heart rate regulation. Thirty-two experimental subjects formed two major groups, one speeding and the other slowing; half of the subjects in each group were signalled for their successes only, and the other half, for their failures only. The session consisted of three phases: Feedback, No Feedback, and Feedback. The data showed that: subjects receiving success signals increased their heart rate significantly more than those receiving failure signals; subjects receiving failure signals decreased their heart rate significantly more than those receiving success signals; there were no differences between the Feedback and No Feedback phases. The results are discussed in terms of their implications for the understanding of the compatibility between task and signal.     

A Proposed Feedback Method For Studying the Inhibition of EEG Responses to Visual Stimuli

A new method for studying inhibition of an electroencephalographic component of the OR to visual stimuli is described. The EEG response is suppression of the occipital alpha following visual stimulation. By a controlled feedback contingency, two stimuli are made to occur in sequence with a controlled time delay after the onset of alpha in the EEG. Inhibition is defined as a lack of EEG response to the first stimulus followed by a response to the second, delayed stimulus. Because the stimuli are feedback with regard to the occurrence of alpha, the dynamics of the alpha - alpha suppression system are different when a response is made to the first stimulus (elicitation of OR to first stimulus) compared to not responding to the first stimulus but responding to the second delayed stimulus (inhibition of OR to the first stimulus).     

Auditory Feedback and Conditioning of the Single Motor Unit

The effects of direct auditory feedback of the electromyogram (EMG) on learning to control a single motor unit (SMU) were investigated. Seventeen human subjects were injected with bipolar fine-wire electrodes into the tibialis anterior muscle. A trial light indicated the onset of a trial. If the subject activated an SMU, a correct light appeared. A non-SMU response was followed by an incorrect light. All subjects received an initial training series with auditory EMG feedback followed by a retest at 2 weeks without EMG feedback. Speed of initial learning was substantially improved by direct EMG feedback. The nature and amount of learning, including the ability to use proprioceptive cues in controlling an SMU, were not affected, nor was retention of learning.