Biofeedback provides users or patients with additional feedback and biological information in real time. Well known in the rehabilitation process, this augmented or extrinsic feedback can support learning. (1)

What is biofeedback and how does it work?

Biofeedback is a well-known technique used in areas of rehabilitation and athletic training to provide patients and athletes with real-time information about body processes. Established for over fifty years in the rehabilitation field, it provides patients with an additional opportunity for therapy.

Studies suggest biofeedback as a therapy option for motor recovery after stroke. (1,2)

By providing feedback, motor control can be re-educated. Through biofeedback, different responses can be assessed and self-control of those responses can be learned. Self-regulation and awareness are one of the goals of biofeedback. By heightening sensory cues and providing feedback, real results can be shown and adaptive strategies can be explored.

In a clinical setting, visual or audio biofeedback is provided by electromyogram (EMG) or other parameters in real time. This additional feedback-loop should help improve a patient’s motor control.

The theory behind it is that either new pathways are developed or that existing cerebral and spinal pathways are recruited. This means that biofeedback may enhance neuroplasticity through additional sensory inputs. (3,4)

Like other evidence-based concepts, biofeedback therapy also should build upon the importance of task-related training and motor learning principles.

Biofeedback, including faded feedback and variations of exercises, is recommended in studies for chronic stroke patients. (5)

In addition to output screens, biofeedback therapy requires specialized equipment to monitor and detect biological information. Signal inputs are necessary for biofeedback therapy. (4)

Different types of biofeedback

There are different types of biofeedback sources used in therapy. The main sources are electromyography (EMG), joint angle and position and pressure plates. The most frequently used feedback system is EMG. EMG can detect muscle activity and is used to reduce the activity of a hyperactive muscle or up-train the recruitment of a weak muscle.

Regardless of what type of biofeedback is applied the display is usually in a relatively simple format. Feedback is given through visual, auditory or tactile stimulation. (3)

Two biofeedback models

Generally, two biofeedback models can be identified.

  1. Direct feedback or operant conditioning where the measured values are displayed in a numerical value. The goal of the feedback is to modify the current type of behavior.
  2. Transformed feedback or feedback learning where the measured values are used to control feedback signals like visual display or auditory and tactile feedback. The effect of the measured action or values are shown and can help to modify behavior and promote learning.

The role of the therapist in these exercises is to answer questions, explain values and to modify tasks. (1,4)

Do I have to be active?

Biofeedback therapy is similar to other therapy techniques used with stroke patients and can be seen not as a treatment but as active training. Just like other skills, practice is necessary for using biofeedback in therapy or at home. The patient should be an active learner and self-responsibility is one key to develop self-activity.
Open access to the necessary knowledge in the form of a therapist or educational tutorial should be a focus. (4)

(EMG) Biofeedback and its use in therapy

EMG is one of the most common physiological values used for biofeedback therapy.
EMG biofeedback therapy has shown positive effects in stroke patients’ upper limb functions by providing visual and auditory feedback in adjusting the muscular tone. Its effectiveness in treating many musculoskeletal conditions is also known. Based on scientific research biofeedback training could be an important therapeutic tool for the rehabilitation of stroke patients. (1,4,6,7)

Other areas of application are dysphagia therapy, balance training, e.g for the reduction of spasticity and muscle strengthening in stroke patients. (5,8,9)

What’s new?

Supplementary use of biofeedback
In practical application, biofeedback can be a supplementary tool to CIMT or task-specific training. Especially in the acute phase of stroke rehabilitation, a multidirectional approach can be practical. (3,11,12)

Multimodal feedback as therapy strategies
The use of feedback combinations and gamification in stroke therapy is one strategy to reach better results. Recently virtual reality (VR) has shown to be useful as a biofeedback signal in improving exercise techniques. (1,12)

What bio information would you like to measure? Do you have experience with biofeedback in therapy?

Bibliography

  1. Giggins, O. M., Persson, U., & Caulfield, B. (2013). Biofeedback in rehabilitation. Journal of NeuroEngineering and Rehabilitation, 10(1), 60. https://doi.org/10.1186/1743-0003-10-60
  2. Langhorne, P., Coupar, F., & Pollock, A. (2009). Motor recovery after stroke: a systematic review. The Lancet Neurology, 8(8), 741–754. https://doi.org/10.1016/S1474-4422(09)70150-4
  3. Huang, H., Wolf, S. L., & He, J. (2006). Recent developments in biofeedback for neuromotor rehabilitation. Journal of Neuroengineering and Rehabilitation, 3, 11. https://doi.org/10.1186/1743-0003-3-11
  4. Frank, D. L., Khorshid, L., Kiffer, J. F., Moravec, C. S., & McKee, M. G. (2010). Biofeedback in medicine: who, when, why and how? Mental Health in Family Medicine, 7(2), 85–91. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/22477926%0Ahttp://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=PMC2939454
  5. Tsaih, P.-L., Chiu, M.-J., Luh, J.-J., Yang, Y.-R., Lin, J.-J., & Hu, M.-H. (2018). Practice Variability Combined with Task-Oriented Electromyographic Biofeedback Enhances Strength and Balance in People with Chronic Stroke. Behavioral Neurology, 2018, 1–9. https://doi.org/10.1155/2018/7080218
  6. Kim, J.-H. (2017). The effects of training using EMG biofeedback on stroke patients upper extremity functions. Journal of Physical Therapy Science, 29(6), 1085–1088. https://doi.org/10.1589/jpts.29.1085
  7. Lourenção, M. I. P., Battistella, L. R., de Brito, C. M. M., Tsukimoto, G. R., & Miyazaki, M. H. (2008). Effect of biofeedback accompanying occupational therapy and functional electrical stimulation in hemiplegic patients. International Journal of Rehabilitation Research, 31(1), 33–41. https://doi.org/10.1097/MRR.0b013e3282f4524c
  8. Benfield, J. K., Everton, L. F., Bath, P. M., & England, T. J. (2019). Does Therapy With Biofeedback Improve Swallowing in Adults With Dysphagia? A Systematic Review and Meta-Analysis. Archives of Physical Medicine and Rehabilitation, 100(3), 551–561. https://doi.org/10.1016/j.apmr.2018.04.031
  9. Zadnia, A., Kobravi, H. R., Sheikh, M., & Hosseini, H. A. (2018). Generating the Visual Biofeedback Signals Applicable to Reduction of Wrist Spasticity: A Pilot Study on Stroke Patients. Basic and Clinical Neuroscience Journal, 9(1), 15–26. https://doi.org/10.29252/nirp.bcn.9.1.15
  10. Seok, H., Lee, S. Y., Kim, J., Yeo, J., & Kang, H. (2016). Can Short-Term Constraint-Induced Movement Therapy Combined With Visual Biofeedback Training Improve Hemiplegic Upper Limb Function of Subacute Stroke Patients? Annals of Rehabilitation Medicine, 40(6), 998. https://doi.org/10.5535/arm.2016.40.6.998
  11. Wattchow, K. A., McDonnell, M. N., & Hillier, S. L. (2018). Rehabilitation Interventions for Upper Limb Function in the First Four Weeks Following Stroke: A Systematic Review and Meta-Analysis of the Evidence. Archives of Physical Medicine and Rehabilitation, 99(2), 367–382. https://doi.org/10.1016/j.apmr.2017.06.014
  12. Valdés, B. A., & Van der Loos, H. F. M. (2018). Biofeedback vs. game scores for reducing trunk compensation after stroke: a randomized crossover trial. Topics in Stroke Rehabilitation, 25(2), 96–113. https://doi.org/10.1080/10749357.2017.1394633