Vestibular + proprioception Flashcards
true/false-membranous labyrinth floats in endolymph and is filled with perilymph.
false, it’s floating in perilymph and filled with endolymph.
how are perilymph and endolymph secreted and drained?
peri is secreted by arterioles in periosteum and drained via perilymphatic duct in cochlea aqueduct in temporal bone. endo is secreted by tissues in cochlear duct and drained by endolymphatic duct in vestibular aqueduct in temporal bone.
whats the cause of Meniere’s disease and Labyrinthitis?
excess pressure in peri and endolymph.
what are the otholith organs and where are they located?
they are utricle and saccule and located in vestibule.
what types of movements do utricle and saccule detect?
linear. utricle in horizontal/transverse plane, saccule in sagittal. hair cells located on horizontal floor and medial wall respectively.
what are the receptive tissue patches in otolith organs called?
maculae utriculi and sacculi
true/false, otolith organs are responsive to changes in endolymoh direction.
false, they respond to gravity
true/false, the ampulae in semicircular canals contain maculae as their neuroepithelium
false, macula is for otolith, semicircular canals have crista.
whats gives the heavy weight of otholith organs?
the calcium carbonate otoliths scattered on otolithic membrane.
what are the types of sensory hair cells in vestibular system?
flask shaped, and cylinder shaped.
where are the cell bodies of the vestibular sensory neurons located?
in the vestibular ganglion within internal auditory meatus.
where are the sensory receptors for proprioception located?
muscle spindle and golgi tendon organs
axon type for proprioception of golgi and muscle spindle?
golgi-1b,
spindle 1a
types of intrafusal muscles?
nuclear chain fibres and nuclear bag fibres
types of afferents to intrafusal fibres?
annulospiral endings-primary type 1a axons, flower-spray endings-type 2a
in the spinal cord the type 1a axons from annulospiral ending synapse with……which provide motor input to extrafusal.
alpha motor neurons
what is friedreich’s ataxia associated with ?
the atrophy of spinocerebellar pathways and hypoplasia of sc and DRG.
from what parts of body does the dorsal spinocerebellar tract get info and where does it synapse?
trunk and lower limbs below T6. synapses in clarke’s nucleus which is present from c8-L2, within lamina 7.
what info does anterior spinocerebellar tract carry and where does it synapse?
muscle tension from lower limb and trunk below L3, also attempted movement, synapses in lamina 5-7
what info does the cuneocerebellar tract carry and where does it synapse?
muscle stretch and tension from upper limb and trunk, above c8, synapse in lateral cuneate nucleus -exist above T6.
what info does rostral spinocerebellar carry and where does it synapse?
muscle tension of upper limb and trunk, above C8, synapses in lamina 7.
