BIOFEEDBACK

What is Biofeedback? A clinical technique that involves recording electrical activity generated in body systems that are not generally felt to be under voluntary control. Uses an instrument that measures, processes & provides feedback reinforcing information via visual or auditory signals E.g. a tone gets lower when blood pressure goes down, etc.. Used for rehabilitation & research purposes It has numerous legitimate clinical applications, but some of its practitioners have strayed far from science.

Biofeedback Units 4 types of Units: Peripheral temperature, Finger Phototransmission, Electrical resistance units/ Skin Conductance Activity Electromyography (EMG), EMG - most typically used form of biofeedback Scale on unit can be both visual and audio Measured in microvolts, 0-10 scale, or some form of pitch

EMG & Other Units http://www.dynatronics.com/catalog/dsp_pro duct.cfm?ccats_id=D832477C-F4D0-11D5- AB25-0050DAB32CA6 http://www.bio- medical.com/results_igeneric.cfm?inventory_ _igeneric=emg

Biofeedback Units Peripheral temperature units Indirect measure of the diameter of peripheral blood vessels Easily seen in toes & fingers Variations in body reactions change temperature  temperature indicates relaxed state  temperature indicates stress, fear, anxiety Measured in degrees Fahrenheit

Biofeedback Units Finger Phototransmission Measured indirectly using a Photoplethysmograph Monitors amount of light reflected by subcutaneous tissues based on amount of blood flow As blood volume increases the amount of light detected decreases Monitor finger pulse

Biofeedback Units Electrical resistance units/ Skin Conductance Activity Measures amount of perspiration on the skin Sweat contains salt which increases electrical conductivity Passes a small current through the fingers (volar surface) and/or palm Measures impedance of electrical current Lie detector testing

Lie Detectors

Biofeedback Units Electromyographic (EMG) Measures electrical activity in skeletal muscle May be very simple to very complex Take-home models Electrodes – you will mostly see surface electrodes Active electrodes: Detects electrical activity from muscle contraction & converts into visual or auditory signals Reference electrode (ground electrode): Filters “noise” or unwanted electrical activity in the environment (other electromagnetic energy); Point of reference to compare the electrical activity recorded by the active electrodes

EMG Units

Indications for EMG Use Facilitation for muscle reeducation Restoration of neuromuscular function Increase muscular strength Promotion of relaxation of spasm Reduction of muscle guarding Assistance with pain control Neurological Conditions (following stroke, spinal cord injury, cerebral palsy, incontinence)

Advantages for using EMG Provides feedback with a chance to make appropriate small changes in performance that are immediately noted & rewarded Patient learns early in rehab to do something for him/herself instead of relying on the athletic trainer Proven to reduce myofascial pain, migraine & tension headache pain and stress reduction With neuromuscular effects, biofeedback helps with input that is lost from receptor

Contraindications If movement of a joint or isometric contractions are contraindicated Conditions in which muscle contractions might exacerbate the condition Unhealed tendon grafts, avulsed tendons, 3rd degree tears of muscle fibers Unstable fractures, injury to joint structure, ligaments, capsule or articulating surfaces Generally, if your measurement or procedures might hurt your patient, don’t!

Patient Set-up & Application Shave area if applicable Clean skin to remove all dirt, oil, lotion, etc. Area may have to be mildly abraded if unit is sensitive Secure electrodes OVER the muscle belly. The active electrodes MUST be on target area. Reference electrode may be secured anywhere on the body, but is usually in between the two active electrodes Distance between active electrodes is usually close

Patient Set-up & Application Plug electrode lead(s) into unit Turn unit on Adjust output to desired mode THE PATIENT SHOULD NOT BE DISTRACTED BY OUTSIDE NOISES DURING SESSION. Various protocols