Biofeedback Flashcards
What is biofeedback?
the use of electronic instrumentation to provide objective information (or feedback) to an individual about a physiologic function or response so that the individual becomes aware of his or her response
How is biofeedback used in clinical practice?
it is used to help the patient develop greater voluntary control following injury or dysfunction
______ are instruments of biofeedback
Clinicians
Feedback includes information related to what 2 things?
- Sensations associated with movements itself
- Result of the action relative to some goal or objective
Feedback is ongoing. What does this mean?
It is occurring before, during, and after any motor or movement task
What are 5 types of intrinsic feedback?
- Kinesthetic
- Visual
- Cutaneous
- Vestibular
- Auditory
What are 4 types of extrinsic feedback?
- Knowledge of results
- Verbally
- Mechanically
- Electronically
How do biofeedback instruments work?
They provide moment to moment information about a biologic function
What are the advantages of biofeedback?
- Information is provided with speed and continuity
- EMG biofeedback is sensitive, objective, accurate and quantitative
- Eventually larger changes or improvement in performance can be accomplished
What is the goal of biofeedback?
to teach the patient to perceive these changes without the use of the instrument
What are the 5 things biofeedback instruments measure?
- Peripheral skin temperature
- Finger phototransmission
- Skin conductance activity
- Electroencephalograph (EEG)
- Electromyographic activity (EMG)
What does peripheral skin temperature indicate?
vasoconstriction
What does finger phototransmission indicate?
vasoconstriction or vasodilation
What does skin conductance activity indicate?
sweat gland activity
What does EEG record?
The brain’s spontaneous electrical activity over a period of time
What does EMG record?
electrical activity during muscle contraction
What causes EMG activity?
Changes in potential difference as the ACh binds to receptor sites on the sarcolemma causing depolarization
The amount of tension developed in a muscle is proportional to?
the number of active motor units
What does the pattern of motor unit recruitment depend on?
- Inherent properties of specific motor neurons
- Force required during the activity
- Speed of contraction
Do fast or slow muscle contractions tend to excite larger motor units? Why?
Fast, because they depress smaller motor units
Does biofeedback measure muscle contraction?
No, it measures electrical activity associated with muscle contraction
When can biofeedback readings be compared?
Only when the same equipment is used for all readings
How can electrical activity be amplified?
By using two active electrodes and one ground “reference” electrode
The electrodes are arranged in __polar arrangement
bipolar
How should the 3 electrodes be placed?
- Active electrodes should be placed in close proximity, with the reference electrode placed between the tow of them
Which electrode picks up the electrical activity from the motor units firing in the muscles?
The active electrodes
How are 2 separate signals created?
Because the magnitude of the voltages detected will differ with respect to the reference electrode
What amplifies the difference between the 2 signals?
A differential amplifier
What does the differential amplifier uses to compare the signals of the 2 active electrodes?
the reference electrode
Describe the concept of “raw” activity
After amplification and filtering, the signal is indicative of the true electrical activity within the muscles being monitored and can be referred to the raw activity
The direction of raw EMG polarity is constantly reversing, making it an _____ voltage.
alternating
Biofeedback measures the overall increase and decrease in what?
electrical activity
What does rectification of the wave create?
a pulsed direct current
Following rectification of the wave what can happen to it?
It can be smoothed and integrated
What does smoothing mean?
eliminating the high-frequency fluctuations that are produced with a changing electrical signal
How is the wave integrated?
the area under the curve is measured for a specified period of time
What forms the basis for quantification of EMG activity?
wave integration
What are the 3 questions you must ask in order to determine of a patient is appropriate for biofeedback?
1) Does the patient have a motor impairment that would suggest that the information provided by biofeedback would be of benefit?
2) Do they have the ability for voluntary control?
3) Are they motivated and cognitively aware?
What are the 9 health issues biofeedback is used to help manage?
- Anxiety or stress
- Asthma
- Chemotherapy side effects
- Chronic pain
- Constipation
- High blood pressure
- Incontinence
- Irritable bowel syndrome
- Raynaud’s disease
What are the 7 indications for biofeedback?
- muscle re-education
- regaining neuromuscular control
- increasing isometric and isotonic strength
- relaxation of muscle spasm
- decreasing muscle guarding
- pain reduction
- psychological relaxation
What is the main contraindication to biofeedback?
Any musculoskeletal condition that a muscular contraction might exacerbate
What are some reasons that biofeedback appeals to people?
- It’s non-invasive
- It may reduce or eliminate the need for medications
- It may be a treatment alternative for those who can’t tolerate medications
- It may be an option when medications haven’t worked well
- It may be an alternative to medications for some conditions during pregnancy
- It helps people take charge of their health
Describe the requirements of the electrodes that are used during biofeedback
They must be surface electrodes that are 4 mm to 12.5 mm and have conducting gel with a high salt content
Where should the electrodes be placed?
Near to the muscle being monitored and parallel to the direction of the muscle fibers
The electrodes are able to detect measurable signals that are how far away?
from a distance equal to that of the interelectrode spacing
What does increased spacing between electrodes allow?
other muscles to interfere with signal processing
How does the skin need to be prepared for biofeedback?
Excessive hair, oil, and dead skin have to be removed
What are the 2 types of biofeedback?
Visual and auditory
____ sensitivity should be used for muscle relaxation.
____ sensitivity should be used for muscle re-education.
High
Low
What are some examples of unique biofeedback uses?
- Pelvic Floor Dysfunction
- Stress Urinary Incontinence
- Fecal Incontinence
- Erectile Dysfunction
