Proprioception And Movement Flashcards
define proprioception
sensations in the musculoskeletal system - muscles, tendons and joints
provide info about position and movement of body
describe muscle receptors
Encapsulated intrafusal muscle (parallel to extrafusal) has spindle of afferent nerves at centre - stretching opens mechanical ion gated channels
Thick and thin filaments at end of intrafusal for contracting
decribe golgi tendon organ
Golgi in series with muscle
Afferent neuron and collagen in capsule
When muscle contracts - collagen pulled activating afferent nerve
When muscle stretches - absorbed by muscle so no effect on Golgi
define extrafusal muscle fibres
large majority of muscle fibers that allow the muscle to do work
define intrafusal muscle fibres
specialized receptors that signal (a) the length and (b) the rate of change of length (velocity) of the muscle
covered by afferent nerves
define afferent nerves
wrap around interfusal muscle fibers
primary afferent wrap around centre of all inrafusal to provide info on length and velocity
secondary afferent at end of fibres and only info about length
respond differently to different types of muscle movements
describe joint receptors
Riffini endings in layers of joint capsules
Many types
- offer kinaesthetic info about movement, position and acceleration
Proprioceptive loss
Remove sensory info on limb and joint position
Describe sacks 1985
Woman lose all proprioception
Use vision/environmental feedback
Show we Rely on vision, vestibular system and proprioception for our sense of self
Describe lackner 1988
Vibrate muscle at 100Hz in diff postures produce impossible perceptions
Describe Visio-proprioception
Absence of visual feedback = drift of hand
Can cause conflict - prism distort hand placement and feel as between
Describe welch and warren 1986
vision dominates proprioception 70:30
What is brodmans area 5
Visio-proprioceptive integration
Neutrons respond strongly to position of real hand but also respond to dummy hand position
