The document provides an overview of biofeedback, defining it as a process that helps the mind control body functions through real-time data from various physiological signals. It discusses the mechanisms and instruments used in biofeedback therapy, such as skin conductance monitors and electromyographs, which assist in training the body to respond appropriately to external stimuli. Additionally, it outlines the types of conditions treated with biofeedback, including tension headaches, incontinence, and asthma.

1. Biofeedback
Radhika Chintamani

2. Contents
Definition
Definitions of various system on the basis of biofeedback
Indications
Mechanism
Instruments following the principle of biofeedback

3. Definition
The goal of biofeedback is to unite the mind and the body to make
the conscious, thinking mind more aware and more in control of
what the body is doing.
At its simplest, biofeedback is a process that uses instruments to
make information about the body available to the mind.

6. Mechanism
Using instruments to assist the mind in controlling the body is the basis of
biofeedback. With exercise, the mind can learn to control the body’s signals.
Biofeedback comes in many forms, but all the instruments do have these
three main parts:
1. Signals
2. Instruments
3. Exercises.
Feedback: A skill which the brain understands and revises itself to search for
a proper strategy to deal with the external environment, to impart proper
forces and also to react to the stimulus given externally. Exists in two
varieties: feed-forward (conscious) feedback process and also feed-backward
feedback process (automatic).

7. Feed forward(Anticipatory
model- open loop)
Feed backward (closed loop)
Feed forward control system takes
the data between input and output.
Evidence from catch trial
Eg: patient repeats the movement
and till the normal movement is
performed by him.
It’s a prediction type of system
which helps in detection and
correction of movement or posture
thus preventing fall or causing
abnormal movement.
Faster movement
Evidence is taken from the fact
that subject usually gets to reach
the destination.
Eg: first I ask the patient to move
the normal limb and to look at it.
Then I ask her/him to move the
abnormal limb and correct it
according to the movement of
normal limb.
The look to movement can be
either performed by contralateral
extremity, by the therapist or by
any system till the beep is given to
stop the movement.
Uses sensory
system
• Slower movement

8. Instruments
According to an instruction manual for practitioners titled Biofeedback: A
Practitioner’s Guide, the instruments used in biofeedback have three tasks:
To monitor a signal from the body by skin conductance, myoelectric
sensors
To measure what is monitored by control box
To display what is monitored as meaningful information: by display unit
like computer, speaker or graph machine

10. Finger
phototransmitter
A finger phototransmitter is a small sensor that clips softly to a
patient’s fingertip and uses light to measure vasoconstriction. The
finger phototransmitter shines a small light through the finger’s
blood vessels. The light is then reflected back to the sensor. The
amount of light reflected tells the practitioner what the blood vessels
are doing. Narrow blood vessels hold less blood, and less blood
allows more light to be reflected. Relaxed, open vessels hold more
blood, and more blood blocks more light. The more the light is
blocked, the more blood is flowing in the vessels.

12. Galvanic Skin Response
Galvanic skin response (GSR) monitors indicate how much a person
is sweating by measuring how much electricity can pass through the
skin. Some GSR monitors produce a tiny current of electricity and
are connected to the fingertips or palm of the hand, where many
sweat glands are present. These monitors measure the skin’s ability
to resist passing an electrical current.

13. Second picture
denotes Galvanic
Skin Response.

14. Surface EMG
SEMG: An electromyograph (EMG) is an instrument that records the
electrical signals produced when a muscle gets tense, or contracts.
Muscles produce electricity when they contract. When more muscles
contract, more electricity is produced.
In biofeedback, small EMG sensors are placed on the surface of the
skin to detect the amount of electricity being produced by the
muscles.
The SEMG can help them pinpoint which muscles need to be
relaxed, and the biofeedback practitioner can help the patient learn to
relax those muscles.
The SEMG monitor tells the practitioner and patient immediately
whether the exercises are working.

15. Surface EMG
SEMG biofeedback is used to treat a wide variety of conditions
including tension headaches, incontinence, muscle spasms, and
paralysis. Positive imagery and reinforcement are also used to help
the patient learn to control these muscles. At the same time, patients
might be asked to exercise these muscles and strengthen their ability
to control the action of the muscle and amount of activity.

16. Mechanism of SEMG
Myoeletric signals
received from muscles
Myoeletric signals amplified so
that it becomes readable
Band pass filters pass
certain frequency along
with noise cancellation
Signals are converted to
graphs for visual or
audio for hearing as
output
Output system

17. Biofeedback games
Master-Quest: Pathways to Inward Journeys is a computer-based
game on CD, designed to teach children to relax using deep
breathing. Children first learn to recognize stress in their bodies and
then practice abdominal breathing and muscle relaxation
The Journey to Wild Divine is another computer-based game that
also teaches relaxation and deep breathing.

19. Instrument which can be used as
biofeedback devices
Sr. No Instrument Uses
1. Isokinetic device Stengthening
+Biofeedback
2. Virtual reality Strengthening +Balance
+Biofeedback
3. Wii Fii Nintendo ----do----
4. X-sense body suit Movements, JPS,
Biofeedback
5. Mox daily activity
monitor
----do----

20. Conditions treated with biofeedback
therapy are
Asthma
Raynaud’s disease (affects blood
flow)
Irritable bowel syndrome
Hot flashes
Nausea and vomiting associated
with chemotherapy
Incontinence
Headaches
Irregular heartbeats (cardiac
arrhythmias)
Epilepsy
Can be added to
strengthen program
Low back ache
Neck pain
ACL rehabilitation
Osteoarthritis

21. THANK YOU