Thermal biofeedback and lower extremity blood flow in adults with diabetes: is neuropathy a limiting factor?

Thermal biofeedback may be a useful adjunctive technique for enhancing cutaneous blood flow in patients with lower-extremity vascular complications of diabetes. However, autonomic, sensory, and/or motor neuropathies may impair vasomotion and limit the ability to alter blood flow and achieve significant foot warming with thermal biofeedback. We examined nerve function associated with four common types of diabetic neuropathy (sympathetic–autonomic, vagal–autonomic, sensory, and motor), hypothesizing that both sympathetic–autonomic and sensory neuropathies would limit the acquisition of biofeedback-mediated foot warming. Twenty-four participants with diabetes mellitus (19 with type II and 5 with type I) received a nerve conduction study and neurological evaluation of the upper and lower extremities. Hand temperature, foot temperature, and electrodermal gradient at the toes were monitored across six thermal biofeedback sessions. Participants were able to significantly raise p < .01) foot temperatures across sessions, an average of 2.2°F. Consistent with our hypotheses, 41% of the variance in foot warming was explained by lower-extremity sympathetic–autonomic and sensory nerve function tests. This study demonstrated that a general diabetic population, including patients with mild-to-moderate neuropathy, can increase skin perfusion with thermal biofeedback. As hypothesized, lower-extremity sympathetic–autonomic and sensory neuropathies interfered with foot warming.     

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.     

How Does Biofeedback Reduce Clinical Symptoms and Do Memories and Beliefs Have Biological Consequences? Toward a Model of Mind-Body Healing

Changes in the magnitude and direction of physiological measures (EMG, EEG, temperature, etc.) are not strongly related to the reduction of clinical symptoms in biofeedback therapy. Previously, nonspecified perceptual, cognitive, and emotional factors related to threat perception (Wickramasekera, 1979, 1988, 1998) may account for the bulk of the variance in the reduction of clinical symptoms. The mean magnitude of these previously nonspecified or placebo factors is closer to 70% whenboththe therapist and patient believe in the efficacy of the therapy. This powerful placebo effect is hypothesized to be anelicitedconditioned response (Wickramasekera, 1977a, 1977c, 1980, 1985) based on the memory of prior healings. These memories of healing are more resistant to extinction if originally acquired on a partial rather than continuous reinforcement schedule. High and low hypnotic ability in interaction with threat perception (negative affect) is hypothesized to contribute to both the production and reduction of clinical symptoms. High and low hypnotic ability respectively are hypothesized to be related to dysregulation of the sympathetic and parasympathetic arms of the autonomic nervous system. Biofeedback is hypothesized to be most effective for reducing clinical symptoms in people of low to moderate hypnotic ability. For people high in trait hypnotic ability, training in self-hypnosis or other instructional procedures (e.g., autogenic training, progressive muscle relaxation, mediation, CBT, etc.) will produce the most rapid reduction in clinical symptoms.     

The Effects of Respiratory Sinus Arrhythmia Biofeedback on Heart Rate Variability and Posttraumatic Stress Disorder Symptoms: A Pilot Study

Recent studies have found a significant association between PTSD and low heart rate variability (HRV), a biomarker of autonomic dysregulation. Research indicates that respiratory sinus arrhythmia (RSA) biofeedback increases HRV while reducing related pathological symptoms. This controlled pilot study compared RSA biofeedback to progressive muscle relaxation (PMR) as adjunctive interventions for 38 persons with PTSD symptoms in a residential treatment facility for a substance use disorder. Both groups were assessed at pre-intervention and 4-week post-intervention. Group × time interactions revealed significantly greater reductions in depressive symptoms and increases in HRV indices for the RSA group. Both groups significantly reduced PTSD and insomnia symptoms and a statistical trend was observed for reduced substance craving for the RSA group. Increases in HRV were significantly associated with PTSD symptom reduction. Overall, these results provide preliminary support for the efficacy of RSA biofeedback in improving physiological and psychological health for individuals with PTSD.     

Characteristics of Resonance in Heart Rate Variability Stimulated by Biofeedback

As we previously reported, resonant frequency heart rate variability biofeedback increases baroreflex gain and peak expiratory flow in healthy individuals and has positive effects in treatment of asthma patients. Biofeedback readily produces large oscillations in heart rate, blood pressure, vascular tone, and pulse amplitude via paced breathing at the specific natural resonant frequency of the cardiovascular system for each individual. This paper describes how resonance properties of the cardiovascular system mediate the effects of heart rate variability biofeedback. There is evidence that resonant oscillations can train autonomic reflexes to provide therapeutic effect. The paper is based on studies described in previous papers. Here, we discuss the origin of the resonance phenomenon, describe our procedure for determining an individual's resonant frequency, and report data from 32 adult asthma patients and 24 healthy adult subjects, showing a negative relationship between resonant frequency and height, and a lower resonant frequency in men than women, but no relationship between resonant frequency and age, weight, or presence of asthma. Resonant frequency remains constant across 10 sessions of biofeedback training. It appears to be related to blood volume.     

Respiratory Sinus Arrhythmia Biofeedback Therapy for Asthma: A Report of 20 Unmedicated Pediatric Cases Using the Smetankin Method

This multiple case study describes pulmonary function changes in 20 asthmatic children from 30 consecutive cases undergoing biofeedback training for increasing the amplitude of respiratory sinus arrhythmia (RSA). The Smetankin protocol was used, which, in addition to RSA biofeedback, includes instructions in relaxed abdominal pursed-lips breathing. Ten individuals were excluded, including 6 who had been taking asthma medication, 2 who developed viral infections during the treatment period, and 2 who dropped out prior to completing treatment. Patients each received 13 to 15 sessions of training. Asthma tended to be mild, with mean spirometric values close to normal levels. Nevertheless, significant improvements were noted in 2 spirometry measures taken during forced expiratory maneuvers from maximum vital capacity: FEV₁ and FEF50. These preliminary uncontrolled data suggest that the Smetankin protocol warrants further evaluation as a nonpharmacological psychophysiological treatment for this condition, although these data could not definitively prove that the method is effective.     

Restoration of Vagal Tone: A Possible Mechanism for Functional Abdominal Pain

Functional abdominal pain (FAP) causes disruption of daily activities/missed school days, over utilization of healthcare, unnecessary surgeries, and anxiety in 10–15% of children. Its etiology is not clearly understood, however the success of several clinical protocols suggests that autonomic dysregulation is a factor. In this study autonomic activity, including heart rate variability (HRV), was compared between children with FAP and a comparison group. Twenty children with FAP and 10 children without FAP between the ages of 5 and 17 years old were compared on autonomic regulation using an ambulatory system at baseline and 8 weeks later. Children with FAP participated in 6 sessions of HRV biofeedback aimed at normalizing autonomic balance. At baseline, children with FAP appear to have more autonomic dysregulation than children without FAP. After completing HRV biofeedback, the FAP group was able to significantly reduce their symptoms in relation to significantly increasing their autonomic balance. In a sample of children with FAP, it appears that HRV biofeedback treatment improved their symptoms and that a change in vagal tone was a potential mediator for this improvement. The present study appears to point to excessive vagal withdrawal as an underlying mechanism of FAP.     

A Scoring System for Capnogram Biofeedback: Preliminary Findings

Labored breathing and irregularities in the breathing pattern may be assessed by capnography; and, an abnormal capnogram wave form may often be rectified with the help of capnogram biofeedback. Clinical experience suggests this may relieve dyspnea but to what degree, for how long and for what conditions have not been determined; the issue is complex and much remains to be discovered. The more that can be learned about the various capnogram irregularities, the more effectively such information will guide us in therapy and research. To this end a 15-category capnogram disordered breathing scale (Landis CDBS) was developed to provide a measure of disordered breathing. The CDBS score is the ratio of the total number of abnormal capnogram forms to the total number of capnogram configurations in the test sample, expressed as a percentage. The total score as well as an accounting of each abnormal scoring category was tabulated for each subject. In this retrospective and preliminary study, findings of a normal comparison group were compared with capnogram data for 3 clinical groups: asthma, anxiety/panic attacks, and patients with diverse stress-related somatic symptoms. Mean CDBS scores were: a low 14% for the Normal group compared with 64% for the Asthma group; 66% for the Anxiety patients; and 47% for the Somatic group. Each group was characterized by distinctive clusters of capnogram abnormalities. As there are methodological limitations to this small group study, the findings require validation. However, as an introduction to the scoring system and because of its potential clinical value we present this paper now.     

The Raynaud's Treatment Study: Biofeedback Protocols and Acquisition of Temperature Biofeedback Skills

The Raynaud's Treatment Study (RTS) compared temperature biofeedback training and a behavioral control procedure (frontalis EMG biofeedback) with nifedipine-XL and a medication placebo for treatment of primary Raynaud's phenomenon (RP) in a large (N = 313) multicenter trial. The present study describes the RTS biofeedback protocols and presents data on the acquisition of digital skin temperature and frontalis EMG responses in the RTS. The findings point to substantial problems with acquisition of physiological self-regulation skills in the RTS. Only 34.6% of the Temperature Biofeedback group (N = 81) and 55.4% of the EMG Biofeedback group (N = 74) successfully learned the desired physiological response. In contrast, 67.4% of a Normal Temperature Biofeedback group (N = 46) learned hand warming. Multivariate analysis found that coping strategies, anxiety, gender, and clinic site predicted acquisition of hand-warming skills whereas variables related to RP disease severity did not. Physiological data showed vasoconstriction in response to the onset of biofeedback and also found that performance in the initial sessions was critical for successful acquisition. These findings indicate that attention to the emotional and cognitive aspects of biofeedback training, and a degree of success in the initial biofeedback sessions, are important for acquisition.     

Mold Sensitivity in the Allergic Respiratory Diseases

A study to determine the role of mold allergens in the allergic respiratory diseases was made by reviewing the skin sensitivity reactions to molds of 257 consecutive cases of asthma and/or rhinitis in southwestern British Columbia. Failure to adequately seek out and to treat even minor mold allergy was noted to be a frequent cause of therapeutic failure or of only limited success. Apparently bearing a consistent relation to age and being most prevalent in the mature adult, allergy to fungi appeared to develop slowly and insidiously. The incidence of mold sensitivity was 78.5% and exceeded that of house dust sensitivity by 3.1%. Evidence of clinical sensitivity was present in excess of 52.4% of mold-sensitive patients. Asthmatic patients showed a greater incidence of sensitivity to molds and to multiplicity of species than did patients with rhinitis only. The hypothesized evolution of rhinitis to asthma appeared to be paralleled by the acquisition of sensitivity to increasing numbers of species of fungi. This suggests that the development of sensitivity to multiple mold species may be an etiologic factor in the production of the asthmatic state.     

A controlled trial of internet-based cognitive-behavioural therapy for panic disorder with face-to-face support from a general practitioner or email support from a psychologist

Background Panic disorder (PD) is one of the most common anxiety disorders seen in general practice, but provision of evidence-based cognitive-behavioural treatment (CBT) is rare. Many Australian GPs are now trained to deliver focused psychological strategies, but in practice this is time consuming and costly.Objective To evaluate the efficacy of an internet-based CBT intervention (Panic Online) for the treatment of PD supported by general practitioner (GP)-delivered therapeutic assistance.Design Panic Online supported by GP-delivered face-to-face therapy was compared to Panic Online supported by psychologist-delivered email therapy.Methods Sixty-five people with a primary diagnosis of PD (78% of whom also had agoraphobia) completed 12 weeks of therapy using Panic Online and therapeutic assistance with his/her GP (n = 34) or a clinical psychologist (n = 31). The mean duration of PD for participants allocated to these groups was 59 months and 58 months, respectively. Participants completed a clinical diagnostic interview delivered by a psychologist via telephone and questionnaires to assess panic-related symptoms, before and after treatment.Results The total attrition rate was 20%, with no group differences in attrition frequency. Both treatments led to significant improvements in panic attack frequency, depression, anxiety, stress, anxiety sensitivity and quality of life. There were no statistically significant differences in the two treatments on any of these measures, or in the frequency of participants with clinically significant PD at post assessment.Conclusions When provided with accessible online treatment protocols, GPs trained to deliver focused psychological strategies can achieve patient outcomes comparable to efficacious treatments delivered by clinical psychologists. The findings of this research provide a model for how GPs may be assisted to provide evidence-based mental healthcare successfully.     

Voluntarily Produced Increases in Heart Rate Variability Modulate Autonomic Effects of Endotoxin Induced Systemic Inflammation: An Exploratory Study

Exposure of healthy people to lipopolysaccharide (LPS; endotoxin) produces a pro-inflammatory response, subjective symptoms, and decreased heart rate variability (HRV). Given the efficacy of HRV biofeedback (BF) for treating asthma, the large autonomic effects of HRV BF, and the link between vagus nerve activity and inflammation, we hypothesized that HRV BF would dampen the acute manifestations of systemic inflammation induced by LPS challenge. Healthy participants age 18-40 were randomly assigned to four-one-hour training sessions of either HRV BF (n = 6) or a control 15/min paced breathing condition (n = 5) prior to acute experimentally induced LPS exposure. Participants were coached to do the procedures for 10 min each at five hourly time points after LPS injection, and then 2 h later. Subjective symptoms, HRV parameters, and plasma cytokine levels were measured at each time point, 2 h afterward, and the following morning. Participants were able to perform the procedures both during four pre-exposure training sessions and while experiencing LPS-induced symptoms. The HRV BF group showed significant attenuation of the LPS-induced decline in HRV for the 6 h following LPS exposure, suggesting that HRV BF decreased autonomic dysfunction produced by LPS-induced inflammation. HRV BF also reduced symptoms of headache and eye sensitivity to light, but did not affect LPS-induced levels of pro-inflammatory cytokines or symptoms of nausea, muscle aches, or feverishness. Further evaluation of HRV BF appears to be warranted among patients with inflammatory conditions.     

Evidence of association between interferon regulatory factor 5 gene polymorphisms and asthma

Asthma is a heterogeneous disorder hallmarked by chronic inflammation in the respiratory system. Exacerbations of asthma are correlated with respiratory infections. Considering the implication of interferon regulatory factor 5 (IRF5) in innate and adaptive immunity, we investigated the preferential transmission patterns of ten IRF5 gene polymorphisms in two asthmatic family cohorts. A common IRF5 haplotype was found to be associated with asthma and the severity of asthmatic symptoms. Stratified analysis of subgroups of asthmatic individuals revealed that the associations were more pronounced in nonatopic asthmatic individuals. In addition, the risk alleles of IRF5 polymorphisms for asthma were almost completely opposite to those for autoimmune disorders. Our study provides the first evidence of association between IRF5 and asthma, and sheds light on the related but potentially distinct roles of IRF5 alleles in the pathogenesis of asthma and autoimmune disorders.     

Applied Psychophysiology: Beyond the Boundaries of Biofeedback (Mending a Wall, a Brief History of Our Field, and Applications to Control of the Muscles and Cardiorespiratory Systems)

The field of applied psychophysiology overlaps a number of others, from behavioral and psychosomatic medicine to Eastern disciplines and complementary medicine. Although the proliferation of societies and professional identities across these fields emphasizes this diversity, it also may hinder growth. The history of our field is one of innovation, often at odds with conventional wisdom and practice. It is important that this innovativeness not be sacrificed in a justified quest for professional respectability. This paper reviews the earliest research in biofeedback and applied psychophysiology, and modern applications and interpretations in the areas of muscular and autonomic control, including progressive relaxation and heart rate variability biofeedback, and draws parallels to disciplines of Yoga, QiGong, and Zen practices and their psychophysiological effects.     

Biofeedback therapy in the colon and rectal practice

In coloproctology, biofeedback has been used for more than 20 years to treat patients with fecal incontinence, constipation, and rectal pain. It can be performed in a number of conditions with minimal risk and discomfort. However, it does require the presence of some degree of sphincter contraction and rectal sensitivity. Biofeedback can be time-consuming and demands motivation. The purpose of this paper is to review the indications, methodology, and results of anorectal biofeedback in the treatment of these disorders. Mean success rates for biofeedback range from 72.3% for fecal incontinence of diverse etiology, 68.5% for constipation attributable to paradoxical puborectalis syndrome, and 41.2% for idiopathic rectal pain. However, criteria to define success vary tremendously among researchers and there is a tendency to indicate biofeedback in a myriad of conditions when other therapeutic options, including surgery, fail or are inappropriate. These factors make comparison of the results difficult and reinforce the need for randomized controlled trials and studies assessing long-term follow-up. In summary, biofeedback is a simple, cost-effective, and morbidity-free technique and remains an attractive option, especially considering the complexity of the functional disorders of the colon, rectum, anus, and pelvic floor.     

Biofeedback in medicine: who,when, why and how?

Biofeedback is a mind-body technique in which individuals learn how to modify their physiology for the purpose of improving physical, mental, emotional and spiritual health. Much like physical therapy, biofeedback training requires active participation on the part of patients and often regular practice between training sessions. Clinical biofeedback may be used to manage disease symptoms as well as to improve overall health and wellness through stress management training. Research has shown that biofeedback interventions are efficacious in treating a variety of medical conditions, and many Americans are turning to biofeedback and other less traditional therapies for their routine healthcare.Clinical biofeedback training is growing increasingly popular in the USA, as many people are seeking out relatively new approaches to healthcare. This article provides an overview of clinical biofeedback training, outlines two models of training, details research which has established how effective biofeedback is in patients with a given disease, and describes who should be referred for biofeedback training.     

Biofeedback-assisted relaxation therapy in neurocardiogenic syncope: a pilot study

This controlled pilot study explored the effects of biofeedback assisted relaxation (BFRT) in neurocardiogenic syncope. Twenty-two patients who completed a 2-week pretest, were randomized to either treatment or wait list control, followed by a 2-week posttreatment/control period. Treatment comprised electromyograph and thermal biofeedback, autogenic and progressive relaxation, and symptom-specific recommendations. Significant differences (p < .05) between groups were observed in the headache index and loss of consciousness, favoring the BFRT group. Both groups decreased state anxiety and depression. The Millon Behavioral Health Inventory was used to assess patients' coping style and adjustment to illness. The majority of the adult participants evidenced illness overreaction, preoccupation with illness, depressive feelings, and tendencies to nonadherence to therapy. BFRT is of potential benefit to patients with neurocardiogenic syncope, but further study is necessary to define the influence of coping style on outcome.     

Applications of biofeedback to the treatment of asthma: a critical review

Both muscular and respiratory biofeedback procedures have been employed in attempts to reduce symptoms of bronchial asthma. Research relating to these approaches is reviewed in the present article. Biofeedback training both for facial muscle relaxation and for respiratory resistance decrease improves short-term pulmonary function in asthmatic individuals. These forms of training represent promising avenues for the management of asthma. However, unqualified endorsement of these procedures is premature, at the present time, since their influence on asthma-related variables other than pulmonary function has not been determined and since their long-term effects have not been investigated.     

Applications of biofeedback to the treatment of asthma: A critical review

Both muscular and respiratory biofeedback procedures have been employed in attempts to reduce symptoms of bronchial asthma. Research relating to these approaches is reviewed in the present article. Biofeedback training both for facial muscle relaxation and for respiratory resistance decrease improves short-term pulmonary function in asthmatic individuals. These forms of training represent promising avenues for the management of asthma. However, unqualified endorsement of these procedures is premature, at the present time, since their influence on asthma-related variables other than pulmonary function has not been determined and since their long-term effects have not been investigated.