M1-L18: Ax Vestibular Flashcards
What is the vestibular system?
- An appreciation of the complexity and importance of this sensory and motor system generally occurs when the system is not functioning as it should. (It is a quiet achiever when functioning normally).
- The vestibular system however is a unifying system for other sensory systems particularly visual, proprioceptive sensory information. The vestibular system plays a most essential role in movement and postural control particularly with respect to orientation and supporting gaze stability.
- The vestibular system has both a sensory and motor elements. The anatomical components of this system are extensive.
What are the 5 various elements in the vestibular system?
- Peripheral receptor apparatus ( utricle, saccule and 3 semicircular canals)
- Central vestibular nuclei
- The vestibule-ocular network
- The vestibule-spinal network
- The vestibulo-thalmic-cortical network
What does tthe vestibular system look like?
What are 5 types of perpheral vestibular receptors?
- Semicircular canals: detecting angular acceleration
- Otoliths: utricle and saccule respond to gravity + linear acceleration.
- Utricle - more sensitive to horizontal acceleration,
- Saccule - more sensitive to vertical acceleration.
- A hair cell is the common receptor cell for this motion sensor system.
- Mechanical deflection of hair cells initiate nerve impulses.
What are semi-circular canals?
detecting angular acceleration
What are otoliths?
utricle and saccule respond to gravity + linear acceleration.
What are utricles?
more sensitive to horizontal acceleration
What are saccules?
more sensitive to vertical acceleration.
What is a hair cell?
A hair cell is the common receptor cell for this motion sensor system.
______ of hair cells initiate nerve impulses
Mechanical deflection
What is the central vestibular nuclei?
the vestibular nuclei processes positional and movement information
What is the vestibulo-ocular network?
stabilizes images on the retina & produces eye movement opposite to head movt : e.g. consider the importance of stable vision for learning to read and write.
Extremely difficult to learn when head is moving
What is the vestibulo-spinal network?
influences muscle tone and produces postural adjustments of the head and body
Post-rotatory nystagmus
What is the vestibulo-thalamic-cortical network?
conscious perception of motion and spatial orientation occurs from an amalgamation of vestibular, visual and somatosensory input at the thalmic -cortical level
What is the International Classification of Functioning Health and Disability (ICF): Hearing and Vestibular functions?
What are the characteristics of “low vestibular registration (doesn’t detect)” (1) and “hypersensitivity to vestibular stimuli (over sensitive)”(1) for SENSES in SENSATION for vestibular?
What are the characteristics of “avoids/dislikes” (1) and “overseeks/persevarates”(1) for ENGAGE in SENSATION for vestibular?
What is NOMINATES in SENSATION for vestibular?
What are the characteristics of “unable to perceive stimulus timing” (1) and “- or + unable to perceive sensory intensity”(1) for NOMINATES in SENSATION for vestibular?
What are the characteristics of “extinction” (1) and “localised hypersensitivity”(1) for SYMMETRY in SENSATION for vestibular?
What are the characteristics of “poor/delayed position adjustments” (1) and “excessive position adjustment”(1) for ADJUSTS in SENSATION for vestibular?
What are the characteristics of “under-responds to stimulus” (1) and “over-responds to stimulus”(1) for TUNES in SENSATION for vestibular?
What are the characteristics of “under-responds to vestibular stimulus” (1) and “over-responds to vestibular stimulus”(1) for INTEGRATES in SENSATION for vestibular?
What is one physical examination finding of INTEGRATES in SENSATION for vestibular?
Physical examination: Infant is visually exploring toys whilst concomitantly integrating ‘somatosensory information’ and vestibular information and achieving head and body orientation to gravity, weight shifting, positive supporting and equilibration whilst continuing to play with toys with motivating visual, tactile and auditory properties .
What are the characteristics of “unresolved sensory conflict/mismatch” (1) and “detects sensory confluct appropriately”(1) for OVERRIDES in SENSATION for vestibular?
What are the characteristics of “unsafe- accidental injury, risky, poor control” (1) and “too safe- efar, avoidance, low experience”(1) for NORMAL in SENSATION for vestibular?
