Spinal Reflexes and Proprioception

Question 1

What is the topographical organisation of motor neurons?

Answer 1

Proximal limb muscles- medial in spinal cord
Distal limb muscles- lateral
Control of extensors- ventral
Control of flexors- proximal

Question 2

What is the difference between intrafusal and extrafusal muscle fibres?

Answer 2

Intrafusal muscle fibres are inside muscle spindles and are responsible for changing spindle length and therefore, sensitivity.
Extrafusal muscles are responsible for force generation.

Question 3

True or false? The tendon reflex (myotatic reflex) involves the use of the Golgi tendon organ,

Answer 3

False, it involves the use of motor spindle fibres.