Week 10 Lecture

Question 1

What did Charles Sherrington quote in 1953 about cognitive decision making?

Answer 1

life’s goal is an act, not a thought

Question 2

What are 3 key aspects of the motor systems?

Answer 2

1. hierarchical and parallel organisation
2. sensory input guides output
3. nature and locus of control change to learning (conscious to automatic)

Question 3

What are physical actions performed by

Answer 3

muscles

Question 4

Muscles act under what?

Answer 4

tensions

Question 5

Alpha motor neurons + muscle fibres equal what?

Answer 5

Motor unit

Question 6

How is muscle activity measured?

Answer 6

using electromyography (EMG)

Question 7

What are golgi tendon organs

Answer 7

• embedded in tendons
• tendons connect to muscle to bone
• GTOs detect muscle tension

Question 8

What are muscle spindles?

Answer 8

• embedded in muscle tissue
• detect changes in muscle length (stretch receptors)
• have their own muscle control system

Question 9

What are simple reflexed controlled by?

Answer 9

circuits in the spinal cord

Question 10

What impacts directly onto motor neurons and act to counteract muscle stretch?

Answer 10

sensory afferents (muscle spindles) synapse

Question 11

What is the stretch reflex?

Answer 11

monosynaptic

Question 12

Is withdrawal reflex monosynaptic?

Answer 12

no

Question 13

What does monosynaptic mean

Answer 13

serves to maintain limb stability

Question 14

Action is mediated by multiple descending pathways, which are what 2 tracts?

Answer 14

pyramidal and extrapyramidal

Question 15

Damage to the basal ganglia would result in what?

Answer 15

difficulty in learned movements

Question 16

What is the neocerebellum?

Answer 16

newest part (outer layers) involved in motor planning

Question 17

What is vestibulocerebellum?

Answer 17

involved in balance, significantly affected by alcohol

Question 18

What are the 3 divisions of the cerebellum?

Answer 18

1. neocerebellum
2. spinocerebellum
3. vestibulocerebellum

Question 19

What are the secondary motor areas involved in?

Answer 19

planning on movement, rhythmic coordination, higher order coordination, anything which involved two limbs

Question 20

Is sensory feedback required for action? (severed dorsal route)

Answer 20

no, sensory feedback is not required for action.

Question 21

What is the theory of endpoint control?

Answer 21

the hypothesis that movements are planned based on the final goal of movement (not planning how to get there).

Question 22

What are some questions which are asked in the neural coding of movements?

Answer 22

What are the neurons coding? muscle activation? direction? position?

Question 23

If a monkey are using different grips and therefore different muscles, what is the correlation between each grip?

Answer 23

muscle activation is important for coding, regarding what that muscle is.

Question 24

Can we use robots to pick up neural signals from the brain to control their movements?

Answer 24

yes, observed in rat experiments, thinking about something can activate neural activity which can move the robotic arm

Question 25

Basal ganglia are important for movement and mediating what?

Answer 25

response competition; the most active response "wins", gets released

Question 26

the output neurons of the basal ganglia to the thalamus are what?

Answer 26

inhibitory

Question 27

The direct pathway from the striatum inhibits the basal ganglud. Therefore:

Answer 27

there is less (inhibitory) output into the thalamus, this means it is the greatest driver to the cotex

Question 28

The indirect pathway excites the basal ganglia, therefore:

Answer 28

the basal ganglia has a greater inhibitory output onto the thalamus, and less cortical drive

Question 29

Parkinson's disease has what affect to the basal ganglia?

Answer 29

loss of dopamine production, affecting the direct pathway; less drive to thalamus and lack of movement

Question 30

How does Huntington's disease affect the basal ganglia?

Answer 30

reduced activity in the indirect pathway, increased cortical excitation/movement

Question 31

What is one way to help Parkinson's disease?

Answer 31

deep brain stimulation