Neuroleptic-like electroencephalographic changes in schizophrenics through biofeedback

Nine schizophrenic patients participated in a study which explored whether EEG feedback techniques could effect changes in the EEG similar to those associated with neuroleptic-induced improvement. During five sessions, each patient was presented feedback signals which continuously reflected the discrepancy between characteristics of the patient's EEG power spectral profile and spectral profile characteristics associated by past research with neuroleptic induced clinical improvement. Significant within-session changes were observed for two of three EEG power spectrum bands of interest. No significant session-to-session EEG changes were observed. The results suggest that the EEG of schizophrenics can be temporarily altered, using feedback techniques, in a way that mimics the EEG changes that have been shown to occur with neuroleptic induced clinical improvement.     

Behavioral and electroencephalographic correlates of 40-Hz EEG biofeedback training in humans

Two groups of eight adults successfully trained with biofeedback for increases in 40-Hz EEG responses in left or right hemispheres also demonstrated significant 40-Hz EEG increases during baseline periods, and increases in the contralateral hemisphere during training periods. No changes in heart rate, 40-Hz EMG, or 21- to 31-Hz beta, alpha, or theta EEG occurred over training days. Three subjects returning for additional training demonstrated suppression of 40-Hz EEG. A group of four subjects experiencing daily bidirectional training produced substantial within-session control of 40-Hz EEG but no changes over days. Data from posttraining tests without feedback for successful subjects in both groups indicated significant control of 40-Hz EEG responses in the initial parts of these sessions, and some correlated changes in other EEG responses. Measures of successful subjects' experiences during training and control tests indicated awareness of changes in subjective concomitants of EEG responses. This study suggests further strategies for research on behavioral correlates of EEG activity.     

Distinct translatome changes in specific neural populations precede electroencephalographic changes in prion-infected mice

Selective vulnerability is an enigmatic feature of neurodegenerative diseases (NDs), whereby a widely expressed protein causes lesions in specific cell types and brain regions. Using the RiboTag method in mice, translational responses of five neural subtypes to acquired prion disease (PrD) were measured. Pre-onset and disease onset timepoints were chosen based on longitudinal electroencephalography (EEG) that revealed a gradual increase in theta power between 10- and 18-weeks after prion injection, resembling a clinical feature of human PrD. At disease onset, marked by significantly increased theta power and histopathological lesions, mice had pronounced translatome changes in all five cell types despite appearing normal. Remarkably, at a pre-onset stage, prior to EEG and neuropathological changes, we found that 1) translatomes of astrocytes indicated reduced synthesis of ribosomal and mitochondrial components, 2) glutamatergic neurons showed increased expression of cytoskeletal genes, and 3) GABAergic neurons revealed reduced expression of circadian rhythm genes. These data demonstrate that early translatome responses to neurodegeneration emerge prior to conventional markers of disease and are cell type-specific. Therapeutic strategies may need to target multiple pathways in specific populations of cells, early in disease.     

Rehabilitation of an electrical burn patient through thermal biofeedback

A 22-year-old male subject, with high-voltage electrical burns to one wrist, utilized differential relaxation and visual biofeedback to increase skin temperature in the damaged hand. Through 14 thermal biofeedback and passive relaxation sessions, the subject was able to produce temperature increases in his damaged hand of up to 21 degrees F, which considerably diminished the pain. Healing, feeling, and movement control seemed to progress with extreme rapidity, suggesting that axoplasmic transport was greatly enhanced.     

Rehabilitation of an electrical burn patient through thermal biofeedback

A 22-year-old male subject, with high-voltage electrical burns to one wrist, utilized differential relaxation and visual biofeedback to increase skin temperature in the damaged hand. Through 14 thermal biofeedback and passive relaxation sessions, the subject was able to produce temperature increases in his damaged hand of up to 21°F, which considerably diminished the pain. Healing, feeling, and movement control seemed to progress with extreme rapidity, suggesting that axoplasmic transport was greatly enhanced.The authors gratefully acknowledge the assistance of Dr. Ranjit Singh, M.B., FRCP (C).     

Biochemical changes associated with thermal biofeedback treatment of hypertension

Fifty-two hypertensive patients whose blood pressure (BP) was controlled on two medications received either 16 sessions of thermal biofeedback (n = 30) for hand warming or 8 sessions of progressive muscle relaxation (n = 22) prior to medication withdrawal. A number of biochemical measures, including plasma norepinephrine (NEPI) (supine and standing), plasma renin activity, plasma aldosterone, and urinary sodium and potassium, were taken before treatment and after treatment while medication remained constant. Results for the biofeedback-treated patients showed significant reductions in mean arterial pressure as well as in both supine and standing NEPI, while the other biochemical measures were unchanged. There were no significant changes on any variable for the relaxation-treated patients. Although the group data support a reduction in peripheral sympathetic tone as associated with the decrease in BP for the thermal biofeedback condition, dose-response relations were not significant.     

Biochemical changes associated with thermal biofeedback treatment of hypertension

Fifty-two hypertensive patients whose blood pressure (BP) was controlled on two medications received either 16 sessions of thermal biofeedback (n=30) for hand warming or 8 sessions of progressive muscle relaxation (n=22) prior to medication withdrawal. A number of biochemical measures, including plasma norepinephrine (NEPI) (supine and standing), plasma renin activity, plasma aldosterone, and urinary sodium and potassium, were taken before treatment and after treatment while medication remained constant. Results for the biofeedback-treated patients showed significant reductions in mean arterial pressure as well as in both supine and standing NEPI, while the other biochemical measures were unchanged. There were no significant changes on any variable for the relaxation-treated patients. Although the group data support a reduction in peripheral sympathetic tone as associated with the decrease in BP for the thermal biofeedback condition, dose-response relations were not significant.This research was supported by a grant from NHLBI, HL-27622.     

Quantification of sleepiness through principal component analysis of the electroencephalographic spectrum

Although circadian and sleep research has made extraordinary progress in the recent years, one remaining challenge is the objective quantification of sleepiness in individuals suffering from sleep deprivation, sleep restriction, and excessive somnolence. The major goal of the present study was to apply principal component analysis to the wake electroencephalographic (EEG) spectrum in order to establish an objective measure of sleepiness. The present analysis was led by the hypothesis that in sleep-deprived individuals, the time course of self-rated sleepiness correlates with the time course score on the 2nd principal component of the EEG spectrum. The resting EEG of 15 young subjects was recorded at 2-h intervals for 32-50 h. Principal component analysis was performed on the sets of 16 single-Hz log-transformed EEG powers (1-16 Hz frequency range). The time course of self-perceived sleepiness correlated strongly with the time course of the 2nd principal component score, irrespective of derivation (frontal or occipital) and of analyzed section of the 7-min EEG record (2-min section with eyes open or any of the five 1-min sections with eyes closed). This result indicates the possibility of deriving an objective index of physiological sleepiness by applying principal component analysis to the wake EEG spectrum.     

Methods of electroencephalographic signal analysis for detection of small hidden changes

The aim of this study was to select and evaluate methods sensitive to reveal small hidden changes in the electroencephalographic (EEG) signal. Two original methods were considered.     

Academic courses in biofeedback

The data presented here represent a sampling of the activities in programs offering academic courses in biofeedback that responded to the Education Committee's effort to develop a directory of such courses. A diversity of type and number of training experiences, equipment, resources, and approaches to training are represented. The committee is currently working on a format to share the wealth of course materials gathered in addition to the directory, which has already been published (Biofeedback Society of America, 1987).     

Quantitative electroencephalographic changes due to middle cerebral artery occlusion by endothelin 1 in conscious rats.

The powerful vasoconstrictor peptide endothelin-1 (ET1) has been shown to reduce local cerebral blood flow in brain areas supplied by the middle cerebral artery (MCA) to a pathologically low level upon intracerebral injection adjacent to the MCA. This reduction manifests itself as an ischemic infarct, that is fully developed within 3 days after ET1 injection. The aim of the present study is to examine the effect of ET1 on electroencephalographic (EEG) activity. ET1 was microinjected unilaterally at a dose of 60 pmol in 3 microl of saline to the MCA in conscious rats. EEG signals were recorded from the frontoparietal cortical area, supplied by MCA, from the first up to the fourteenth day after ET1 injection. EEG activity was analyzed by the fast Fourier transformation. A significant shift to a lower EEG frequency, i.e., augmentation of slow waves and a reduction of alpha-like and faster EEG waves was found post-ET1. This effect was maximal after 3-7 days when the most severe destruction of neurons in this cortical area occurs, as has been previously demonstrated. The results suggest that the quantitative EEG analysis may provide useful additional information about the functional disturbances associated with focal cerebral ischemia.     

Cognitive factors in biofeedback therapy

The role that the client's cognitions(viz., his self-statements and images) play in each of the various phases of biofeedback training is examined. Biofeedback training is conceptualized as including three phases: initial conceptualization, skills-acquisition and -rehearsal, and transfer of treatment. Cognitive-behavior modification procedures to alter or employ the clients' cognitions at each of these phases of treatment are described. A cognitive theory of self-control is offered, postulating a three-stage mediational change process whereby:(1) the client must become an observer of his behavior and physiological responses;(2) this recognition becomes the cue to emit incompatible cognitions and behaviors; and, finally,(3) the content of the client's cognitions following change influences the generalization and persistence of treatment effects. The implications of this theory for biofeedback training are discussed.     

Self-control procedures in biofeedback: A review of temperature biofeedback in the treatment of migraine

It is argued that in order to optimize the achievement of self-control and to evaluate the clinical effects of biofeedback three skills should be included in training and assessment, namely: (1) the ability of voluntary control with external feedback, (2) the ability of voluntary controlwithout external feedback, and (3) the ability toapply the self-control skill in critical situations in everyday life. A review of the literature concerning temperature-biofeedback in the treatment of migraine headaches shows that the research from this point of view is in a rather poor state of affairs and that no definite conclusion can in fact be drawn about the degree of self-control which has been achieved and hence of the ultimate clinical value of biofeedback.This study was supported by grant no. 80/66 from the Bank of Sweden Tercentenary Foundation.