Post on 23-Dec-2015
Biological Basis of Equilibrium Disorders
rina_susilowati@ugm.ac.id
rina_susilowati@ugm.ac.id 2011
Vision - external reference
Primary organ of equilibrium: Vestibular system internal reference
Somatosensory internal & external reference
Brain
Information about the body's position
Skeletal muscles
Postural adjustment BALANCE
rina_susilowati@ugm.ac.id 2011
Information about the body's position
If the brain receives inadequate information about the body's position
dysequilibrium
rina_susilowati@ugm.ac.id 2011
Otolith organs Utricle Sacculus
Semicircular canals Superior Posterior Horizontal
Vestibular organ
Linear acceleration of the head
Rotational acceleration of the head
Static tilt
Gravitationforce
rina_susilowati@ugm.ac.id 2011
rina_susilowati@ugm.ac.id 2011
rina_susilowati@ugm.ac.id 2011
rina_susilowati@ugm.ac.id 2011
Otolith organs Utricle: horizontal
Sacculus: vertical
Linear acceleration of the head
Lateral vestibular nuclei
rina_susilowati@ugm.ac.id 2011
AmpullaeSemicircular canals
Rotational acceleration of the head
Semicircular Canals
Superior
Posterior
Horizontal
Medial vestibular nuclei
rina_susilowati@ugm.ac.id 2011
The semicircular canals detect angular acceleration. There are 3 canals, corresponding to the three dimensions in which you move, so that each canal detects motion in a single plane. The actual hair cells sit in a small swelling at the base called the ampula
rina_susilowati@ugm.ac.id 2011
Rotation around y axis
Rotation around x axis
Translationalx,y,z axes
otolith organs
Rotational
semicircular canals
Rotation around z axisVestibular Navigation
rina_susilowati@ugm.ac.id 2011
Scarpa ganglion
Vestibular nuclei
Ventral posterior nucleus complex of thalamus
both sides
Vestibular cortex(Posterior parietal cortex)
rina_susilowati@ugm.ac.id 2011
Connections underlying the
vestibulo-ocular reflex
initiates compensatory eye movement
keep the eyes focused on a target during head movement
Scarpa’s ganglion
Midbrain
Pons
Rostral medullaMedial vestibular nucleusCaloric test
rina_susilowati@ugm.ac.id 2011
Caloric test
rina_susilowati@ugm.ac.id 2011
Balance – Anxiety links
Hypothalamus, amygdala, limbic cortexAnxiety
Parabrachial nucleus
somatic & visceral sensory Vestibular nuclei Spinal cord
Balance
ANS control
rina_susilowati@ugm.ac.id 2011
Clinical corelation: vertigo
rina_susilowati@ugm.ac.id 2011
Clinical corelation: vertigo
rina_susilowati@ugm.ac.id 2011
• Peripheral / otological – 85% (NIH); Indonesia?– ototoxic drug, infections,
vestibular neuroma, head trauma or natural aging process
• Central– central vestibular system,
psychogenic
Vertigo
rina_susilowati@ugm.ac.id 2011
Cerebellum: coordination
Medial Vestibular nucleus
Mid-Pons
Rostral Medulla
Spinal cord
Descending projections from vestibular nuclei to the spinal cord Vestibulocervical Vestibulospinal reflexes
Lateral Vestibular nucleus
Vestibular nuclei receive inputs from cerebellum
Motor cortex
Somatosensory
rina_susilowati@ugm.ac.id 2011
Familial Ataxia
rina_susilowati@ugm.ac.id 2011
Thank you