This study validates real-time biofeedback for lumbopelvic control training in baseball. The lumbopelvic region is crucial for generating kinetic energy in pitching. Real-time biofeedback enhances ...training effectiveness and reduces injury risk. The validity and reliability of this system were examined.
This study was to investigate the validity and reliability of the real-time biofeedback system for lumbopelvic control training.
Twelve baseball players participated in this study, with data collected in two sessions separated by a week. All participants needed to do the lateral slide exercise and single-leg squat exercise in each session. Pelvic angles detected by the real-time biofeedback system were compared to the three-dimensional motion capture system (VICON) during training sessions. Additionally, pelvic angles measured by the biofeedback system were compared between the two training sessions.
The real-time biofeedback system exhibited moderate to strong correlations with VICON in both exercises: lateral slide exercise (
= 0.66-0.88,
< 0.05) and single-leg squat exercise (
= 0.70-0.85,
< 0.05). Good to excellent reliability was observed between the first and second sessions for both exercises: lateral slide exercise (ICC = 0.76-0.97) and single-leg squat exercise (ICC = 0.79-0.90).
The real-time biofeedback system for lumbopelvic control training, accurately providing the correct pelvic angle during training, could enhance training effectiveness.
To evaluate the efficacy of MP-3 microperimeter biofeedback fixation training (MBFT) in vision rehabilitation of low-vision patients affected by macular disease with central vision loss.
Seventeen ...eyes (7 age-related macular degeneration, 10 myopic maculopathy) of 17 patients were included in this prospective, interventional study. The preferred retinal locus was determined by comprehensive ophthalmoscopic fundus evaluation including fundus photography, autofluorescence, optical coherence tomography, and microperimetry. The rehabilitation consisted of three 10-min sessions per eye to be performed twice per week for 20 consecutive weeks using the MP-3 microperimeter. Best corrected visual acuity (BCVA), reading speed, mean central sensitivity, the percentages of fixation points within specified regions, bivariate contour ellipse area (BCEA) and the 25-item National Eye Institute visual function questionnaire (NEI-VFQ-25) were recorded pre- and post-training.
The final BCVA, reading speed and mean central sensitivity all showed significant improvements after rehabilitation (P < 0.0001, P = 0.0013, and P = 0.0002, respectively). The percentages of fixation points located within 2° and 4° diameter circles both significantly increased after training (P = 0.0008 and P = 0.0007, respectively). The BCEA encompassing 68.2, 95.4, 99.6% of fixation points were all significantly decreased after training (P = 0.0038, P = 0.0022, and P = 0.0021, respectively). The NEI-VFQ-25 scores were significantly increased at the end of the rehabilitation training (P < 0.0001).
Rehabilitation with MP-3 MBFT is a user-friendly therapeutic option for improving visual function, fixation stability, and quality of life in advanced macular disease.
The prospective study was registered with the Chinese Clinical Trial Registry ( http://www.chictr.org.cn/ ).
ChiCTR2000029586 . Date of registration: 05/02/2020.
This review summarizes my own involvement in heart rate variability (HRV) and HRV biofeedback studies, as a tribute to the late Dr. Evgeny Vaschillo. I first review psychophysiological studies on ...behavioral stress and relaxation performed in my laboratory using an assessment of cardiac parasympathetic activity. Although magnitude of high-frequency (HF) component of HRV corresponding respiratory sinus arrhythmia (RSA) is widely used as an index of cardiac parasympathetic function, a respiratory confound during stress or relaxation may have interfered with the proper assessment of the HF HRV. An enhanced method under frequency-controlled respiration at 0.25 Hz provided a reliable assessment of cardiac parasympathetic activity. I then review findings from HRV biofeedback research in my laboratory. Based on the hypothesis that RSA measured as an HF component of HRV represents cardiorespiratory resting function, it was demonstrated that HRV biofeedback before sleep enhanced the magnitude of HF HRV during sleep, a cardiorespiratory resting function. Moreover, by focusing on the spectral peak of the low-frequency (LF) component of HRV, paced breathing at the LF-peak frequency was shown to increase baroreflex sensitivity. Finally, I describe the potential of slow-paced abdominal breathing (i.e.,
Tanden
breathing) performed in Zen meditation. The concept of
Tanden
breathing as described in a regimen from early modern Japan is introduced, and recent research findings on slow-paced abdominal breathing are summarized. Future research directions of slow-paced abdominal breathing are also discussed.
The efficacy of pelvic floor muscle training (PFMT) alone and in combination with biofeedback (BFB), electrical stimulation (ES), or both for urinary incontinence in men following prostatectomy is ...inconclusive.
The purpose of this study was to determine whether PFMT works well alone or in combination with BFB, ES, or both in comparison with a control.
The databases Ovid Medline, EMBASE, CENTRAL, Scopus, and Web of Science, and the specialized register of the Citroen Incontinence Review Group were searched from study inception to August 2017. Abstract proceedings from urological meetings, including the European Association of Urology and the American Urological Association, were also searched.
Randomized controlled trials that compared PFMT alone and PFMT with ES, BFB, or both and no treatment, placebo, or sham were included in the review.
Two independent reviewers completed data extraction and quality appraisal. The Grading of Recommendations, Assessment, Development, and Evaluation tool was used for quality appraisal. Meta-analysis was done with software used for preparing and maintaining Cochrane reviews.
Methodological flaws in the included studies limited internal validity.
PFMT alone, PFMT plus BFB and ES, and PFMT plus ES were more effective than the control for urinary incontinence following prostatectomy. The effect of PFMT plus BFB on postprostatectomy incontinence remains uncertain.
Background
Various approaches to physical rehabilitation may be used after stroke, and considerable controversy and debate surround the effectiveness of relative approaches. Some physiotherapists ...base their treatments on a single approach; others use a mixture of components from several different approaches.
Objectives
To determine whether physical rehabilitation approaches are effective in recovery of function and mobility in people with stroke, and to assess if any one physical rehabilitation approach is more effective than any other approach.
For the previous versions of this review, the objective was to explore the effect of 'physiotherapy treatment approaches' based on historical classifications of orthopaedic, neurophysiological or motor learning principles, or on a mixture of these treatment principles. For this update of the review, the objective was to explore the effects of approaches that incorporate individual treatment components, categorised as functional task training, musculoskeletal intervention (active), musculoskeletal intervention (passive), neurophysiological intervention, cardiopulmonary intervention, assistive device or modality.
In addition, we sought to explore the impact of time after stroke, geographical location of the study, dose of the intervention, provider of the intervention and treatment components included within an intervention.
Search methods
We searched the Cochrane Stroke Group Trials Register (last searched December 2012), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 12, 2012), MEDLINE (1966 to December 2012), EMBASE (1980 to December 2012), AMED (1985 to December 2012) and CINAHL (1982 to December 2012). We searched reference lists and contacted experts and researchers who have an interest in stroke rehabilitation.
Selection criteria
Randomised controlled trials (RCTs) of physical rehabilitation approaches aimed at promoting the recovery of function or mobility in adult participants with a clinical diagnosis of stroke. Outcomes included measures of independence in activities of daily living (ADL), motor function, balance, gait velocity and length of stay. We included trials comparing physical rehabilitation approaches versus no treatment, usual care or attention control and those comparing different physical rehabilitation approaches.
Data collection and analysis
Two review authors independently categorised identified trials according to the selection criteria, documented their methodological quality and extracted the data.
Main results
We included a total of 96 studies (10,401 participants) in this review. More than half of the studies (50/96) were carried out in China. Generally the studies were heterogeneous, and many were poorly reported.
Physical rehabilitation was found to have a beneficial effect, as compared with no treatment, on functional recovery after stroke (27 studies, 3423 participants; standardised mean difference (SMD) 0.78, 95% confidence interval (CI) 0.58 to 0.97, for Independence in ADL scales), and this effect was noted to persist beyond the length of the intervention period (nine studies, 540 participants; SMD 0.58, 95% CI 0.11 to 1.04). Subgroup analysis revealed a significant difference based on dose of intervention (P value < 0.0001, for independence in ADL), indicating that a dose of 30 to 60 minutes per day delivered five to seven days per week is effective. This evidence principally arises from studies carried out in China. Subgroup analyses also suggest significant benefit associated with a shorter time since stroke (P value 0.003, for independence in ADL).
We found physical rehabilitation to be more effective than usual care or attention control in improving motor function (12 studies, 887 participants; SMD 0.37, 95% CI 0.20 to 0.55), balance (five studies, 246 participants; SMD 0.31, 95% CI 0.05 to 0.56) and gait velocity (14 studies, 1126 participants; SMD 0.46, 95% CI 0.32 to 0.60). Subgroup analysis demonstrated a significant difference based on dose of intervention (P value 0.02 for motor function), indicating that a dose of 30 to 60 minutes delivered five to seven days a week provides significant benefit. Subgroup analyses also suggest significant benefit associated with a shorter time since stroke (P value 0.05, for independence in ADL).
No one physical rehabilitation approach was more (or less) effective than any other approach in improving independence in ADL (eight studies, 491 participants; test for subgroup differences: P value 0.71) or motor function (nine studies, 546 participants; test for subgroup differences: P value 0.41). These findings are supported by subgroup analyses carried out for comparisons of intervention versus no treatment or usual care, which identified no significant effects of different treatment components or categories of interventions.
Authors' conclusions
Physical rehabilitation, comprising a selection of components from different approaches, is effective for recovery of function and mobility after stroke. Evidence related to dose of physical therapy is limited by substantial heterogeneity and does not support robust conclusions. No one approach to physical rehabilitation is any more (or less) effective in promoting recovery of function and mobility after stroke. Therefore, evidence indicates that physical rehabilitation should not be limited to compartmentalised, named approaches, but rather should comprise clearly defined, well‐described, evidenced‐based physical treatments, regardless of historical or philosophical origin.
The current study aimed to identify specific feedback mechanics and psychological processes that may contribute to positive outcomes in biofeedback applications for anxiety regulation. Specifically, ...using a dismantling study design, the unique impact of visualizations that directly mirror users' breathing was examined in relation to anxiety regulation as well as locus of control and self-efficacy. Following an anxiety induction, participants (
= 67) were randomly assigned to play one of two variations of a biofeedback video game. In both versions, players' in-game movement was contingent on their breathing; however, the experimental condition additionally included visualizations that directly mirrored players' breathing. Changes in self-reported state anxiety and physiological arousal were measured as well as the level of internal control and self-efficacy participants experienced while playing the game. Results showed that all participants were able to effectively reduce their anxiety and arousal, but no condition differences were found. Implementing mirroring visualizations did not contribute to individuals' ability to self-regulate nor their self-efficacy or locus of control above and beyond receiving feedback based on their in-game movement. Overall, individuals who experienced higher self-efficacy and a stronger internal locus of control were better able to regulate their anxiety, but no clear links were found with changes in self-reported physiological arousal. In light of these results, we recommend the continued exploration of the role of specific design choices and intervention components as well as underlying mechanisms of change in biofeedback interventions, especially pertaining to how individuals perceive themselves and their ability to change.
Brain machine interfaces (BMI) connect brains directly to the outside world, bypassing natural neural systems and actuators. Neuronal-activity-to-motion transformation algorithms allow applications ...such as control of prosthetics or computer cursors. These algorithms lie within a spectrum between bio-mimetic control and bio-feedback control. The bio-mimetic approach relies on increasingly complex algorithms to decode neural activity by mimicking the natural neural system and actuator relationship while focusing on machine learning: the supervised fitting of decoder parameters. On the other hand, the bio-feedback approach uses simple algorithms and relies primarily on user learning, which may take some time, but can facilitate control of novel, non-biological appendages. An increasing amount of work has focused on the arguably more successful bio-mimetic approach. However, as chronic recordings have become more accessible and utilization of novel appendages such as computer cursors have become more universal, users can more easily spend time learning in a bio-feedback control paradigm. We believe a simple approach which leverages user learning and few assumptions will provide users with good control ability. To test the feasibility of this idea, we implemented a simple firing-rate-to-motion correspondence rule, assigned groups of neurons to virtual "directional keys" for control of a 2D cursor. Though not strictly required, to facilitate initial control, we selected neurons with similar preferred directions for each group. The groups of neurons were kept the same across multiple recording sessions to allow learning. Two Rhesus monkeys used this BMI to perform a center-out cursor movement task. After about a week of training, monkeys performed the task better and neuronal signal patterns changed on a group basis, indicating learning. While our experiments did not compare this bio-feedback BMI to bio-mimetic BMIs, the results demonstrate the feasibility of our control paradigm and paves the way for further research in multi-dimensional bio-feedback BMIs.
Biofeedback potentially provides non-invasive, effective psychophysiological interventions for psychiatric disorders. The encompassing purpose of this review was to establish how biofeedback ...interventions have been used to treat select psychiatric disorders anxiety, autistic spectrum disorders, depression, dissociation, eating disorders, schizophrenia and psychoses to date and provide a useful reference for consultation by clinicians and researchers planning to administer a biofeedback treatment. A systematic search of EMBASE, MEDLINE, PsycINFO, and WOK databases and hand searches in Applied Psychophysiology and Biofeedback, and Journal of Neurotherapy, identified 227 articles; 63 of which are included within this review. Electroencephalographic neurofeedback constituted the most investigated modality (31.7 %). Anxiety disorders were the most commonly treated (68.3 %). Multi-modal biofeedback appeared most effective in significantly ameliorating symptoms, suggesting that targeting more than one physiological modality for bio-regulation increases therapeutic efficacy. Overall, 80.9 % of articles reported some level of clinical amelioration related to biofeedback exposure, 65.0 % to a statistically significant (
p
< .05) level of symptom reduction based on reported standardized clinical parameters. Although the heterogeneity of the included studies warrants caution before explicit efficacy statements can be made. Further development of standardized controlled methodological protocols tailored for specific disorders and guidelines to generate comprehensive reports may contribute towards establishing the value of biofeedback interventions within mainstream psychiatry.
In contemporary western societies stress is highly prevalent, therefore the need for stress-reducing methods is great. This randomized controlled trial compared the efficacy of self-help physical ...activity (PA), mindfulness meditation (MM), and heart rate variability biofeedback (HRV-BF) in reducing stress and its related symptoms. We randomly allocated 126 participants to PA, MM, or HRV-BF upon enrollment, of whom 76 agreed to participate. The interventions consisted of psycho-education and an introduction to the specific intervention techniques and 5 weeks of daily exercises at home. The PA exercises consisted of a vigorous-intensity activity of free choice. The MM exercises consisted of guided mindfulness meditation. The HRV-BF exercises consisted of slow breathing with a heart rate variability biofeedback device. Participants received daily reminders for their exercises and were contacted weekly to monitor their progress. They completed questionnaires prior to, directly after, and 6 weeks after the intervention. Results indicated an overall beneficial effect consisting of reduced stress, anxiety and depressive symptoms, and improved psychological well-being and sleep quality. No significant between-intervention effect was found, suggesting that PA, MM, and HRV-BF are equally effective in reducing stress and its related symptoms. These self-help interventions provide easily accessible help for people with stress complaints.
Myoelectric control offers a direct interface between human intent and various robotic applications through recorded muscle activity. Traditional control schemes realize this interface through direct ...mapping or pattern recognition techniques. The former approach provides reliable control at the expense of functionality, while the latter increases functionality at the expense of long-term reliability. An alternative approach, using concepts of motor learning, provides session-independent simultaneous control, but previously relied on consistent electrode placement over biomechanically independent muscles. This paper extends the functionality and practicality of the motor learning-based approach, using high-density electrode grids and muscle synergy-inspired decomposition to generate control inputs with reduced constraints on electrode placement. The method is demonstrated via real-time simultaneous and proportional control of a 4-DoF myoelectric interface over multiple days. Subjects showed learning trends consistent with typical motor skill learning without requiring any retraining or recalibration between sessions. Moreover, they adjusted to physical constraints of a robot arm after learning the control in a constraint-free virtual interface, demonstrating robust control as they performed precision tasks. The results demonstrate the efficacy of the proposed man-machine interface as a viable alternative to conventional control schemes for myoelectric interfaces designed for long-term use.