Unit 8 Motor Control

Question 1

What is the role of the skeletal system

Answer 1

To control voluntary movement

Question 2

How are muscles organized around the joints

Answer 2

They are organized as antagonists and synergists

Muscles are connected to the bone via tendons

Question 3

What is the basic anatomy of a muscle

Answer 3

muscle fibres, myofilaments, actin and myosin

Question 4

What is the anatomy of the spinal cord and spinal motor neurons

Answer 4

The neurotransmitter junction contains axons, motor end plates, muscle fibre nucleus, axon terminal branch

Question 5

What are the general steps in a typical muscle contraction

Answer 5

ACh is released ➡️ nAChRs on muscle fibers ➡️ muscle fiber depolarizes ➡️ Ca2+ released into the muscle fiber (from internal stores) ➡️ muscle contracts

Question 6

What is the motor unit

Answer 6

It is a structure containing a motor neuron and the muscle fibers it innervates

Question 7

What is Proprioception

Answer 7

It is information about the position of your body

Question 8

What is the concept of a spinal reflex

Answer 8

Movements controlled by neuronal circuits in the spinal cord

Question 9

What is the sequence of events that occur during a stretch reflex

Answer 9

1. A change in weight is detected
2. Muscles stretch and lengthen causes the activation of the muscle spindle
3. The sensory information is sent to the spinal cord
4. The information is sent back to the motor neurons in the muscle

Question 10

When would you expect muscle spindles to be activated

Answer 10

During muscle lengthening

Question 11

When would you expect Golgi tendon organs to be activated

Answer 11

During muscle contraction

Question 12

What is the concept of a motor plan

Answer 12

A set of commands to muscles that is established prior to the start of a behaviour

Question 13

What is the evidence for a motor plan

Answer 13

Reaction time to stimulus isn’t fast enough to be random. It’s so fast it has to be planned out

Question 14

What is the role of the primary motor cortex (M1)

Answer 14

Different regions of the M1 control different muscles and movements. Neurons in the M1 are active during movement

Question 15

What is the role the non-primary motor cortex

Answer 15

Planning, visualizing and coordinating movement sequences

Question 16

What is the role of the pyramidal tract

Answer 16

Controls voluntary muscle movement

Question 17

What is the role of the cerebellum

Answer 17

receives sensory inputs from vestibular system, proprioceptors, and the other senses. It also sends outputs to motor cortex and motor regions of brainstem

Question 18

What is the role of the basal ganglia

Answer 18

Subcortical network that thought to facilitate desired movement and inhibit unwanted movement.

Question 19

What is OCD

Answer 19

It is when the direct pathway of the basal ganglia is overactive which reduces the capacity to Inhibit behaviours

Question 20

What is Parkinson’s disease

Answer 20

It is when the dopaminergic neuron is degenerating and cannot facilitate movement

Question 21

What is Huntington’s disease

Answer 21

It is when neurodegeneration of neurons in the basal ganglia cause reduced function in the indirect pathway. This happens because of a genetic mutation

Question 22

What are mirror neurons

Answer 22

Active during the execution of a movement and while the animal watches someone else complete the same movement

Question 23

What happens if the cerebellum is damaged

Answer 23

Loss of coordination

Movements become disconnected

Motor learning impact