EQUILIBRIOCEPTION: SENSE OF BALANCE

Presented by: Suhas DeshpandeEE 506 Theory & Practice Biomedical Instrumentation

Dr. Christopher Druzgalski

OUTLINE

Importance Balance as a sense Vestibular system Sensory factors affecting balance Balance disorders Postural diagnosis Postural balance indicator Research and applications References

IMPORTANCE

Dizziness is a common symptom affecting about 30% of people over the age of 65

Difficulty in performing one or more activities of daily living

May have serious outcomes even death Falls are the leading cause of fatal and

non-fatal injuries for old age person 

BALANCE AS A SENSE

A complex activity with interaction from various parts of the body.

Feedback control system

Vestibular system, Nervous system, Eyes, Muscles and tendons

www.ebaumsworld.com/pictures/view/80735176

VESTIBULAR SYSTEM

Semicircular canals detect the rotation

The fluid in the canals moves as our body rotates to produce neurological stimulus

VESTIBULAR SYSTEM

Otolith organs: Saccule and Utricle to detect linear acceleration

Movement of hair cells in the utricle and sacule innervate the neurons during the motion

VESTIBULAR SYSTEM Nervous system Eyes: VOR

(Vestibulo-ocular Reflex)

Stabilizes retinal image during rotation

Maintains the feedback gain of -1

SENSORY FACTORS AFFECTING BALANCE

Vision Provides necessary information for effective navigation

Provides input to the nervous system about the real world

SENSORY FACTORS AFFECTING BALANCE

Vision Vestibular sense Helps in positioning

the head

VOR helps in maintaining the visual fixation

SENSORY FACTORS AFFECTING BALANCE

Vision Vestibular sense Proprioception

Sensory information from muscles, tendons provide feedback of joint position, movement and touch.

Lower limbs input contributes to standing balance.

SENSORY FACTORS AFFECTING BALANCE

Vision Vestibular sense Proprioception Central Nervous

system

Receives feedback from other organs

Sends motor response to other organs

BALANCE DISORDERS

Related to Ear BPPV (Benign

Paroxysmal Positional Vertigo)

Meniere’s disease Labyrinthitis (inner

ear infection)

Related to brain Traumatic Brain

Injury Disorders of CNS Diseqillibrium

POSTURAL DIAGNOSIS

Rotation Tests ENG(Electronystagmography) CDP(Computerized Dynamic

Posturography) MRI CT Scan

POSTURAL DIAGNOSIS

Posturography  Non-invasive specialized technique Study the contributions of vestibular

inputs, visual inputs, somatosensory inputs, central integrating mechanisms and muscular system outputs for postural and balance control

POSTURAL DIAGNOSIS

Posturography Patient stands still in a set of conditions

with eyes open/closed in fixed and sway referenced surface conditions

Three kinds of tests: Sensory Organization Test (SOT), Motor Control Test (MCT) and Adaptation Test (ADT)

POSTURAL DIAGNOSIS

ENG Electrodes placed around the eye Detects the occurrence of a nystagmus

(involuntary eye movement) Ears flushed with warm and then cold

water. Amount of nystagmus measured.

POSTURAL DIAGNOSIS

Rotation tests Patient is seated on a rotary chair Chair rotates/moves in specific manner The eye movements are monitored to

diagnose the problem

POSTURAL BALANCE INDICATOR

Two level sensors: fluid filled tubes Photo-resistor and an LED coupled

detect the off balance position Signal sent to respective vibrators (left

or right or both) The patient senses the vibrations to

regain equillibrium

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RESEARCH AND APPLICATION

Application of human postural balance mechanism to humanoid robots

Study of the zero gravity condition and role of and effect on the human body for astronauts.

REFERENCES1. P. Ingerson, "Postural balance indicator and associated feedback

compensation system," Annual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings, vol. 26, pp. 2484, 2004.

2. V. Panzer, "Biomechanical changes in postural control concurrent with aging," J. Biomech., vol. 22, pp. 1067, 1989

3. F.Horak, "Clinical assessment of balance disorders", Gait & Posture, Volume 6, Issue 1, Pages 76-84

4. L. Kodde, "An application of mathematical models in posturography," J. Biomed. Eng., vol. 4, pp. 44, 1982

5. Hyon. "Integration of multi-level postural balancing on humanoid robots",2009 IEEE International Conference on Robotics and Automation, pp. 1549, 1556

6. http://www.physpharm.fmd.uwo.ca/undergrad/sensesweb/L10Balance/L10Balance.pdf

7. http://vestibular.org/index.php 8. http://www.nidcd.nih.gov/health/balance/balance_disorders.asp9. http://www.dizziness-and-balance.com/index.html10. http://resourcesonbalance.com11. http://spaceline.nasaprs.com/pdf/Astronaut_Study.pdf