LECTURE 11

Question 1

Motor behaviour requires cooperation between which 2 systems

Answer 1

Nervous system (orchestrates plan of action), Musculoskeletal system (execution and ongoing control)

Question 2

Where is motor control ‘located’

Answer 2

NOT localised within the brain, is distributed throughout the central nervous system

Question 3

4 main systems involved in motor planning and execution

Answer 3

1. Lymbic system - deciding to act
2. Association cortex - response selection
3. Projection system - scaling/fine tuning
4. Spinal system - execution/feedback

Question 4

What is the role of the limbic system

Answer 4

Motivation, emotion, learning, memory

Question 5

What parts of the brain are associated with the limbic system

Answer 5

Amygdala, Cingulate gyrus, Hypothalamus, Hippocampus

Question 6

What does the limbic system influence

Answer 6

Endocrine system and autonomic nervous system

Question 7

What do association areas in response selection do?

Answer 7

Integrate sensory and motor functions

Question 8

Where are association cortices located

Answer 8

Near primary sensory cortex of the same type
(eg. Auditory association cortex is next to primary auditory cortex)

Question 9

Role of association cortices

Answer 9

• Recognition of relevant inputs
• Makes sense of input
• Integration of input into motor response

Question 10

What are the appropriate parameters selected during scaling of the motor program

Answer 10

Force, displacement, velocity, body segment, posture, muscle groups

These parameters depend on information from input

Question 11

Anatomy of the projection system

Answer 11

Cerebral cortex (motor cortex, premotor cortex, supplementary motor area, parietal cortex), basal ganglia, cerebellum

Question 12

Anatomy of the spinal system

Answer 12

Brain stem, Corticospinal tracts, spinal cord with central nerves

Question 13

Parameters depend on information from which input sources

Answer 13

Environment, body, task goal

Question 14

Roles of the spinal system in motor control

Answer 14

• Carry information from CNS to neuromuscular (efferent)
• Carry information from periphery to CNS (afferent)
• Information processing at the spinal level - spinal reflexes

Question 15

Are the spinal cord and the spinal column the same thing

Answer 15

NO - spinal cord is a bundle of nerves running from brain to muscles and sensors. The spinal (vertebral) column protects the spinal cord.

Question 16

Where are more than half the neurons in the brain located

Answer 16

Cerebellum

Question 17

What is the cerebellum

Answer 17

Big player in motor control. Activates well in advance of EMG trace, indicates involvement in planning.

Question 18

What happens when the Cerebellum is damaged

Answer 18

Leads to hypotonia and ataxia. Therefore, trouble with coordination, regulation of muscle tone, timing and learning will be experienced

Question 19

What aspects of movement is the Cerebellum involved in

Answer 19

Timing, Learning

Question 20

What is the role of the Basal Ganglia

Answer 20

• Activation or retrieval of movement plans
• Scaling of movement parameters
• Movement preparation

Question 21

What happens when the Basal ganglia is damaged

Answer 21

Huntington’s disease, Parkinson’s

Question 22

What are the characteristics of Huntington’s

Answer 22

Clumsiness, forgetfulness, uncontrollable ballistic movements, dementia

Question 23

What are the characteristics of Parkinson’s

Answer 23

Dopamine deficit which is normally produced in basal ganglia.
Shuffling gait, resting tremor, slow initiation of movements, resistance to tugging

Question 24

What is the role of the Motor Cortex

Answer 24

MC is a trigger center rather than a planning center. Controls muscle activity particularly in distal muscles

Question 25

Signals in MC occur around ____ before electrical activity in muscles which means ___

Answer 25

50ms
NOT involved in planning but are involved in execution

Question 26

The motor cortex is found in which lobe of the brain

Answer 26

Frontal lobe

Question 27

How does the motor cortex represent body areas

Answer 27

Geographically in the motor homunculus. Larger parts of the mapping have more neurons. Greater neurons means better fine tuning of movements

Question 28

What does the premotor cortex control

Answer 28

Proximal muscles; trunk and shoulders

Question 29

Where are anticipatory postural adjusments made

Answer 29

In pre-motor cortex

Question 30

What is the function of the APA’s

Answer 30

Adapts the body position for movements. Prepares postural muscles to stabilise for movements

Question 31

What is the supplementary motor area involved in

Answer 31

Complex movements - two hand movements, movement sequences etc.

Question 32

When does the SMA activate

Answer 32

It is active long before movement onset which indicates high level of planning and production of complex movement sequences

Question 33

What is the parietal cortex

Answer 33

Association between sight and sound, movement and sensory consequence etc.

Question 34

What happens when the parietal cortex is damaged

Answer 34

Apraxia - movements separated not combined
Spatial neglect - people can only see what is directly in front of them and completely neglect other areas

Question 35

What is the function of the brain stem

Answer 35

Transports signals from spinal cord up to rest of brain.
Transports motor commands from NS to motor neurons in spinal cord.