Kinesiology 1080A/B Lecture Notes - Lecture 21: Semicircular Canals, Sagittal Plane, Angular Acceleration
7 Oct 2016
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Lecture 21- March 18th
Proprioception:
• Definition:
o Sensory signals (afferent kinesthesia) regarding position of body in space
Proprioception:
1. Vestibular - not very well studied.
2. Muscle Receptors - (spindles/golgi tendon organs)
3. Joint Receptors - not very well studied
4. Cutaneous Receptors - not very well studied
Vestibular System Has Two Main Structures:
1. Three fluid-filled half circles termed semicircular canals.
• Horizontal canal detects rotation of head around vertical axis (i.e. spinning)
• Anterior and posterior canals detect rotation in the sagittal plane (i.e.,
nodding) and in the frontal plane (i.e., completing a somersault) –the frontal
plane divides the body in half.
• They are also important at detecting angular acceleration.
2. Otolith organs - both contain fluid called endolymph, these structures also contain
cilia.
• Provides information regarding position of head relative to the rest of our
body
• It is sensitive to each directional plane (x,y,z)
• Important in angular acceleration
• We have a loop in each plane!
• Movement of head is an intrinsic movement, (it can be an extrinsic
movement which is the whole body being moved by someone else –aka you
get pushed)
• What happens:
• The endolymph fluid moves.
• It causes the cilia to bend, this sends sensory information
regarding where we are in space out of the vestibular system
and into the CNS.
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Proprioception: definition, sensory signals (afferent kinesthesia) regarding position of body in space. Proprioception: vestibular - not very well studied, muscle receptors - (spindles/golgi tendon organs, joint receptors - not very well studied, cutaneous receptors - not very well studied. It is sensitive to each directional plane (x,y,z) It causes the cilia to bend, this sends sensory information regarding where we are in space out of the vestibular system and into the cns. Otolith organ: detect changes in gravity and acceleration, two components, utricle- detects change in horizontal movement and linear acceleration (e. g. walking) Important for posture prevents you from falling down. Neither of these two structures detect constant velocity they only detect linear acceleration. They are detecting changes in gravity due to acceleration endolymph moves, astronauts have difficulty because the first 2-3 weeks they do not get accurate information from the vestibular system and get sick due to no presence of gravity.
