(S1W2) Control of Muscle Activation part 10

Question 1

What’s the difference in where muscle spindles and Golgi tendon organs are location?

Answer 1

• muscle spindles run along and within the muscle (intrafusal)
• Golgi tendon organs is in series (at the end of the muscle)

Question 2

What do Golgi tendon organs have instead of Ia afferent neurons?

Answer 2

Ib afferent neurons

Question 3

What do Golgi tendon organs detect?

Answer 3

changes in tension/force

Question 4

What happens if a Golgi tendon organ detects too much tension/force?

Answer 4

• sends signal along Ib afferent neuron, via Ib interneuron, along alpha ⍺ motoneuron to inhibit the same muscle it is attached to

Question 5

Fill in the missing labels

Answer 5

1. Ib afferent neuron
2. tendon
3. Golgi tendon organ
4. muscle
5. alpha ⍺ motoneuron

Question 6

Explain, using an example, how the Golgi tendon organ disinhibits the opposite muscle

Answer 6

• during elbow extension, Golgi tendon organ detects too much tension in triceps
• so inhibits the triceps
• but also disinhibits the biceps to pull in the opposite way, doubling the effect
• sends signal along Ib afferent neuron, via Ib interneuron, along alpha ⍺ neuron to opposite muscle (biceps) to excite the biceps
• does this by inhibiting the inhibitor of the biceps (disinhibitation)
• this is trisynaptic excitation

Question 7

What does trisynaptic excitation mean?

Answer 7

exciting a muscle via 3 synapses