Reflexes In Skeletal Muscle

Question 1

What is proprioception? What does it control?

Answer 1

The cognitive 6th sense that allows you to know where your body is in space. Controls balance, posture and walking.

Question 2

What is kinaesthesia?

Answer 2

The ability to feel movement

Question 3

What are the 3 types of muscle sensory receptors?

Answer 3

Muscle spindle
Golgi tendon organ
Joint capsule prioceptors

Question 4

What are the three types of movement? And what are their differences?

Answer 4

Reflex- minimal brain involvement, simplest, spinal cord or brain stem
Rhythmic- combination of reflex and voluntary, requires cerebral cortex, CNS and pattern generators
Voluntary- most complex, cerebral cortex, variety of pathways

Question 5

What is the pattern of control of voluntary movement

Answer 5

1. Sensory input (sensory cortex)
2. Planning and decision making (basal ganglia and cerebellum)
3. Coordination and timing (motor cortex)
4. Execution (cerebellum)
5. Continuous feedback

Question 6

What is an isotonic contraction?

Answer 6

Muscle contracts, shortens and moves the load

Question 7

What is an isometric contraction?

Answer 7

Elastic elements allow for the muscle to stay the same length once it has contracted, does not move the load

Question 8

Muscle spindle

Answer 8

More than 1 in each muscle
Within intrafusal fibres, surrounded by extrafusal fibres
Muscle contracts—> increased firing of alpha motor neurones
Spindle contracts—> increased firing of gamma motor neurones

Question 9

Golgi tendon Organ

Answer 9

Contraction activated sensory neurones
Synapse with inhibitory interneurons
Synapse with and inhibit motor neurones causing muscle relaxation

Question 10

Joint capsule proprioceptors

Answer 10

Type I: small corpuscles
Type II: large corpuscles
Type III: resemble GTO
Type IV: free nerve endings