Lecture 5 - Proprioceptors and muscle sense Flashcards
What is proprioception?
Sense the position and movement of you own limbs
What mediates proprioception?
- Muscle receptors
- Joint capsule receptors
- Cutaneous receptors
What are muscle receptors that contribute to proprioception?
- Muscle spindles
- Golgi tendon organs
What are cutaneous receptors that contribute to proprioception?
- Reffini endings
- Merkel disks
- Field receptors
What are two somatic sensations? [2]
- Epicentric: touch mediated
- Protophatic: pain and temperature
What is the role of proprioceptors?
Signal to the central nervous system information about relation position of body parts
What is muscle sense?
The sensation from receptors in the skeletal muscles
What are muscle spindles?
- Stretch receptors
- Excited by stretching
What are the sensory functions of muscle spindles?
- Stretch detectors
- Primary endings : velocity & position
- Secondary endings: position
What does stretching of intrafusal fibres cause?
- Stretching of sensory endings
- Increases receptor firing rate
What affect can gamma motor neurons have on muscle spindles?
They can adjust the sensitivity/responsiveness
How is the muscle spindle sensitivity regulated?
- Muscle stretched
- Muscle contracts: decreased sensory firing
- Increases gamma-motor neuron activity
What do changes in gamma spindle sensitivity during different tasks lead to?
- The static and dynamic spindle responsiveness is regulated
Where are golgi tendon organs located?
The junction of skeletal muscle and its tendon
What are golgi tendon organs respond to?
Active contractile force