Alpha Motor Neurons

Question 1

Hierarchical organization of motor pathways

Answer 1

Like the Visual cortex, the motor cortex is hierarchically organised but than other way around

From a conceptual level -> response system -> motor implementation

1. Premotor and supplementary motor cortex regions
   1a. Cerebellum, 1b basal ganglia
2. Motor cortex
3. Brainstem
4. Spinal cord

Question 2

Ventral horn

Answer 2

Spinal cord is the final common pathway of all motor output

Alpha Motor neurons are fairly large neurons in the ventral horn (ventral root in the grey matter). They form the basis for the stretch reflex.

Question 3

Alpha motor neuron route

Answer 3

Ventral root; connects to the muscle

Dorsal root; connected tot he muscle spindle, sensory neuron comes into the ventral horn, activates the ventral root

Question 4

Distal vs proximal muscles

Answer 4

Dorsolateral part: distal muscles, important for fine movements

Ventromedial part: proximal muscles, important for posture