biofeedback study guide

what is biofeedback?

information provided from some measuring instrument about a specific biologic function

what is electromyographic (EMG) biofeedback?

the use of electronic or electrochemical instruments to accurately measure, process, and feedback reinforcing information via auditory or visual signals

what is biofeedback commonly used for?

used a lot for incontinence issues

what can be a learned response?

muscle relaxation

what can help the patient develop greater voluntary control in terms of either neuromuscular relaxation or muscle re-education following injury or stroke?

electromyographic biofeedback

what can biofeedback be used for on a muscle?

- work

- relax

what is electromyography?

a clinical technique that involved recording of the electrical activity generated in a muscle for diagnostic purposes

what kind of electrode(s) does electromyography use for measuring electrical activity in the muscle and nerve conduction?

uses with surface or needle electrodes

what can be detected by an electrode placed in close proximity?

changes in potential difference or voltage associated with depolarization

in EMG biofeedback, a nerve fiber conducts an impulse to where?

to the neuromuscular junction

in EMG biofeedback, acetylcholine binds to what?

receptor sites on the sarcolemma inducing a depolarization of the muscle fiber

inducing a depolarization of the muscle fiber through EMG biofeedback creates movement of ions and thus causing what to happen?

an electrochemical gradient around the muscle fiber

based on the principles of electromyography, what does it monitor?

monitors motor unit action potentials (MUAPs) during muscle contractions

biofeedback devices measure what?

the amplitude of MUAPs in microvolts

a biofeedback unit amplifies, filters, rectifies, integrates, and displays what?

the MUAPs in audio and visual formats

the magnitude of the contraction reflects what?

- the number of motor units firing

- the electrode size and placement

- the distance of the active fibers from the recording electrodes

what two parameters are adjusted in EMG biofeedback treatment?

- gain/sensitivity

- threshold/goal

as a goal is accomplished through electromyography what then takes place?

if a goal is accomplished, then the sensitivity will decrease making it harder and requiring more motor units

biofeedback equipment displays the output voltage via what?

- bar graph

- number graph

- liquid crystal display

- oscilloscope screen

what is a peloton?

a type of biofeedback where a bike can be rode "anywhere in the world" which therefore increases motivation

what is the gain parameter?

the amplification of the signal to a size that may be displayed

high gain settings are what?

more sensitive

low gain settings are what?

less sensitive and scaled to high microvoltage

what allows the signal to be views in the middle of the screen so the patient can see what they're doing?

adjusting the gain/sensitivity

what is the threshold/goal parameter?

a predetermined level of muscle activity at which audio/visual feedback is given

what provides a clear goal for the patient and is altered by the practitioner to achieve motor recruitment or inhibition?

a threshold/goal

visual feedback can be what?

sophisticated computer graphics or a simple LCD

auditory feedback may be what?

a click or a tone that sounds when threshold is reached or that becomes quiet when threshold is reached

what is the electromyogram nerve conduction study?

a graphic representation of those electrical currents associated with muscle action

what can be looked at as a form of coaching?

biofeedback

what is the role of biofeedback?

providing the patient with information so that they can make small changes in performance that are immediately rewarded and noted ultimately leading toward improved functional outcomes

what can be set all the way from inhibiting a certain muscle to a functional activity?

biofeedback

biofeedback equipment is designed to do what?

record some aspect that is highly correlated with the physiologic event

what was biofeedback instrumentation designed to do?

- monitor some physiologic event

- objectively quantify these readings, and then interpret the measurements as meaningful information

is a goniometer considered biofeedback? why or why not?

yes, its a type of non-electric biofeedback

biofeedback instruments can be used to measure what?

- peripheral skin surface temperature

- heart rate

- finger photo transmission

- skin electrical conductance activity

- electromagnetic muscle activity

- brain wave activity

- skin condition

- blood pressure

how can biofeedback be used to measure skin electrical conductance activity?

via the galvanic skin response (GSR)

why is biofeedback considered a therapeutic modality?

because it uses different means to provide patients with instant feedback concerning information about physiological function

what can biofeedback be used to do?

- train for relaxation

- treatment of stress related disorders

- increase muscle activity to strengthen or decrease muscle activity in order to overcome spasms

what are 3 examples of stress related disorders?

hypertension, headaches, chronic pain

electrogoniometers, electroencephalographs, and pressure transducers are all examples of what?

biofeedback equipment available

how is the Wii considered biofeedback?

great biofeedback device

- due to gaming and being able to progress and get better

- due to competition to win

what is peripheral skin temperature?

an indirect measure of the diameter of the peripheral blood vessels

during stress, what is the effect on the blood in the body?

it is shunted away from the distal extremities therefore there is a decreased in temperature of the distal extremities

through relaxation exercises, mental visualization, and biofeedback, what is the effect on stress?

it can be reduced which will redirect blood flow to the extremities and result in relaxation to the patient

as vessels dilate, what is delivered to a particular area?

more warm blood thus increasing the temperature in that area

how is peripheral skin temperature measured and with what insrument?

measured using a skin temperature probe called a thermistor that is placed on the finger or toe and velcroed into place

when a patient has vascular headaches, what type of biofeedback is best and why?

- peripheral skin temperature

- used to redirect blood flow in order to decrease blood flow to the brain

peripheral skin temperature is associated with what?

affective states like psychological or emotional states

when will peripheral skin temperature decrease?

with response to fear or stress

where is peripheral skin temperature most commonly seen?

in the fingers and toes where the surrounding tissue warms and cools rapidly

sweat gland activity can be indirectly measured how?

by determining electro-dermal activity

what is sweat gland activity most commonly referred to as?

galvanic skin response

what does sweat contain?

salt that increases electrical conductivity

sweaty skin is ___ conductive than dry skin

more conductive

how is galvanic skin response/skin conductance activity measured?

applies a very small amount of voltage across the skin and measures the impedance of the electrical current in micro-ohm units

where is galvanic skin response/skin conductance activity measurement taken?

usually on the palmar surface of the hand or the volar surface of the fingers where there are a lot of sweat glands

measuring skin conductance is a technique useful in what?

objectively assessing psychophysiologic arousal

where is measuring skin conductance activity most often used?

in lie detector testing

sociopaths will often ___ the skin conductance activity and why?

pass because they do not have the ability to feel empathy and care

normal people will often ___ the skin conductance activity and why?

fail because they care

because of the sympathetic response to stress, this has what affect on heart rate?

HR increases

how is heart rate biofeedback measured?

- uses a finger sensor to detect heart rate

- unit can provide visual/audible feedback for HR

what are used to decrease the sympathetic response and decrease HR?

relaxation techniques

what is the most commonly utilized form of biofeedback in the clinical setting?

electromyographic (EMG) biofeedback

what is going to cause a whole muscle to contract?

synchronous contraction of individual muscle fibers that make up the muscle

muscle fibers are innervated by what?

nerves that collectively comprise a motor unit

the axon of the motor unit conducts an action potential to where?

to the neuromuscular junction where a neurotransmitter is released

as the neurotransmitter binds to receptor sites on the sarcolemma, what occurs?

depolarization of that muscle fiber

what is creating movement of ions and thus an electrochemical gradient around the muscle fiber?

electromyography of muscle contraction

changes in potential difference or voltage associated with depolarization can be detected by what?

an electrode placed in close proximity

the amount of tension developed in a muscle is determined by what?

by the number of active motor units

as more motor units are recruited and the frequency of discharges increases, what increases?

muscle tension

motor units are recruited based on what?

the force required in an activity and NOT on the type of contraction performed for muscle contractions

what is biofeedback used to determine?

the muscle activity

biofeedback does not measure what?

the muscle contraction directly

biofeedback measures the ___ ___ associated with muscle contractions?

electrical activity

what are the indications for biofeedback?

- regaining neuromuscular control

- increasing isometric and isotonic strength of a muscle

- decreasing muscle guarding and muscle spasms from spasticity

- improving pain reduction

- improving the psychological relaxation response

what are the contraindications for biofeedback?

any musculoskeletal condition in which a muscular contraction might increase the symptoms of that condition or would be contraindicated

what are some examples of contraindications for biofeedback?

injury to an area with active bleeding or unstable fracture

can biofeedback be used for a patient with a pacemaker or a pregnant female?

yes, can do!

what kind of impact will the size of the biofeedback electrodes have?

will have no impact on the amplitude of the signal

the size of the biofeedback electrodes should be appropriate for the size of the treatment area and has what range for larger muscles?

from 4mm to 12.5mm for larger muscles

regardless of the size or type of electrodes, there needs to be what in between the electrode and the patient's skin?

a highly conductive interface like gel, paste, or cream

to prepare the skin prior to biofeedback treatment, why should you remove oils, dead skin and excessive hair?

to help reduce electrical impedance and with conduction

to prepare the skin prior to biofeedback treatment, can an alcohol wipe be used or do you have to wash with soap and water?

an alcohol pad may be used

light abrasion with sandpaper or a pumice may be used if what?

skin is calloused or hardened in order to decrease electrical impedance

what is a pumice?

like a buffer at the nail salon

where should the electrodes for biofeedback be placed?

as close to the muscle being monitored as possible

in what direction should the electrodes for biofeedback be placed?

parallel to the direction of muscle fibers to ensure that a better sample of muscle activity is monitored

what 2 meters are there for visual biofeedback?

- analog with a needle

- digital with numbers

visual biofeedback equipment can include what?

- line traveling across an oscilloscope

- light or series of lights that go on and off

- a bar graph

- video games

- meters

how can a bar graph be used as a type of visual biofeedback equipment?

with a bar graph that changes dimension in response to the incoming information

audible biofeedback equipment can include what?

- a tone

- buzzing

- beeping

- clicking

an increase in the pitch of a tone, buzz, or beep, or an increase in the frequency of clicking indicates what?

an increase in the level of electrical activity

a decrease in the pitch of a tone, buzz, or beep, or an increase in the frequency of clicking indicates what?

a decrease in the level of electrical

activity thus relaxing

what are the clinical applications for biofeedback?

- muscle re-education

- relaxation of muscle guarding

- pain reduction due to working on "thing" causing pain

- can use this when a patient has contraindications for electrical stimulation

what is muscle re-education?

regaining neuromuscular control and increasing muscle strength

EMG biofeedback for muscle re-education can be used for what conditions?

- hemiplegia following CVA

- spinal cord injury

- spasticity

- cerebral palsy

- facial paralysis like Bell's palsy

- urinary/fecal incontinence

what are the 2 ways to used 1 channel EMG biofeedback?

- to monitor activation of muscles to retrain after diagnoses such as CVA or knee surgery thus "working"

- to monitor relaxation to train for relaxation of the muscle to decrease pain secondary to the muscle spasms or HA or when trying to stretch a tight muscle thus "relaxing"