Recommended
More Related Content
Similar to Physiology Special senses vestibular system.pptx
Similar to Physiology Special senses vestibular system.pptx (20)
Recently uploaded
Recently uploaded (20)
Physiology Special senses vestibular system.pptx
- 2. Vestibular system • There are five vestibular receptor organs in the inner ear: • The utricle • The saccule and • Three ampulla of semicircular canals.
- 3. • All components of vestibular apparatus contains endolymph ad are surrounded by perilymph Bony labyrinth
- 5. • Vestibular apparatus contains hair cells • The ampulla of the canals, the utricle and saccule have receptors that respond to movement • Hair cells in receptors
- 6. Equilibrium • Equilibrium is the sense of body orientation and motion
- 7. Types of Equilibrium • Static • Linear • Utricle and Saccule • Dynamic • Angular • Semicircular canals
- 8. Semicircular canals • Each canal lies perpendicular to each other • At the point where they meet, the canal is expanded to form the ampulla
- 12. • Vestibule
- 13. Semicircular canals- detect rotational acceleration
- 21. • Hair cells in ampulla are embedded in cupula- gelatinous layer
- 24. • Depolarization in direction of kinocilium • Hyperpolarization in direction opposite to kinocilium
- 25. • Cupula bends opposite to head rotation
- 26. Movement of head on left side • Movement of fluid opposite to head direction i.e right
- 27. • Fluid movement cause cupula or hair cells to bend • Stimulating one side (same) • Inhibiting other side (contralateral)
- 29. If head continues to move • Fluid catches up and move in direction of head
- 30. If head movement stops • Movement of fluid reverse situation occurs
- 32. • Only detects changes in rate of rotational movement • Do not respond when head is motionless or moving in circle at constant speed
- 34. Utricle and saccule • The utricle and the saccule, are housed within two cavities in the vestibule. • Utricle oval shaped adjacent to semicircular canals • Saccule towards cochlea
- 35. • Saccule lie perpendicular to utricle
- 36. Utricle and saccule-detect linear acceleration
- 43. • Plane • Hair cells arangement
- 44. • Hair cells in utricle is arranged vertically • Hair cells in saccule arranged horizontally
- 45. The utricle cells with beat in forward/backward and saccule in Up/down direction
- 46. Utricle detects forward/backward movement
- 47. Saccule detects up/down movement
- 48. Head movement • Utricle hair cells tilt in direction of head tilt due to gravitational force exerted on gelatinous layer
- 49. Body movement • Utricle hair cells displaced by change in horizontal linear movement i.e backward forward or side ways • This person moving forward • Hair cells moving backward
- 50. • When person continues to walk hair cells bend no longer • When person stops hair cell bend in forward direction
- 53. • Saccule responds to tilting head away from horizontal position such as getting up from bed and to vertically directed linear motion
- 54. Vestibular pathway • Nerve fibers coursing from hair cells in vestibular apparatus project to vestibular ganglion (scarpa’s ganglion)
- 58. Vestibular pathway Vestibular Nuclei • Superior • Inferior • Lateral • Medial
- 64. Vestibulo-spinal reflex • Maintain body posture for balancing to prevent fall
- 69. Purpose of vestibulo-ocular reflex is to fix the gaze during head rotation
- 75. Balance is achieved by not only inner ear input but also sight and proprioceptors
Editor's Notes
- Normal balance needs: accurate sensory information from the eyes, proprioceptive receptors and the vestibular labyrinth with coordination of this information within the brain normal motor neural control by the central nervous system of an intact musculoskeletal system: normal muscles and joints