Task 7 - the motor system

Question 1

three levels of motor control

Answer 1

1. high: mental image of your body in space
2. middle: based on past movements
3. low: muscle length tension

Question 2

smooth muscles

Answer 2

involuntary control, innervate by ANS nerve fibers, lining digestive tract and helps blood pressure

Question 3

stratieted muscles

Answer 3

1. cardiac muscle - involuntary, contracts the heart
2. skeletal muscle - somatic motor system, voluntary control, generate behavior –> bone movement around the joints etc.

Question 4

Axial (somatic musculature )

Answer 4

trunk and torso movement

Question 5

proximal (somatic musculature )

Answer 5

moves shoulder, elbow, pelvis and knee joints

Question 6

distal (somatic musculature )

Answer 6

toes and fingers

Question 7

Lateral pathway (brain and spinal cord)

Answer 7

voluntary movement of distal musculature - under direct cortical control

Question 8

cortico spinal tract (brain and spinal cord)

Answer 8

major neuronal pathway providing voluntary motor function. This tract connects the cortex to the spinal cord to enable movement of the distal extremities.

Question 9

Rubrospinal tract (brain and spinal cord)

Answer 9

receives input from frontal cortex

Question 10

Ventromedial pathway (brain and spinal cord)

Answer 10

body position and visual environment, posture and reflex movement

Question 11

vestibulospinal tract (brain and spinal cord)

Answer 11

postural reflexes - keeps head balanced on shoulders at the body moves in space

Question 12

tectospinal tract (brain and spinal cord)

Answer 12

control neck, upper truck and shoulders via superior colliculus input (receives info from the retina, somatosensory and auditory to construct map of the world ) = orient responses

Question 13

pontline reticulospinal tract (brain and spinal cord)

Answer 13

enhances antigravity reflex of the spinal cord

Question 14

medullary rectrospinal tract (brain and spinal cord)

Answer 14

liberates antigravity muscles from reflex control

Question 15

basal ganglia - movement

Answer 15

direct pathway allows it to enhance desired movements and indirect pathway inhibits unwanted movements

Question 16

cerebellum - movement

Answer 16

responsible for sequencing movement (right force, posture, balance)

planned voluntary and multi-joint movements

input from sensory and visual feedback

Question 17

primary motor cortex

Answer 17

much of it is active for all movements

Question 18

premotor area

Answer 18

primarily connects with recticulospinal neurons and innervates proximal motor units

Question 19

supplementary motor area

Answer 19

innervates distal motor units via axons

Question 20

posterior parietal cortex

Answer 20

receives input from the primary somatosensory cortex and visual input

Question 21

prefrontal cortex

Answer 21

decision making - when to initiate the movement (association areas of the neocortex)

Question 22

what happens if this structures suffer any damage (5)

Answer 22

• parkinsons disease: willed movements, rgidity and tremors
• degeneration of substancial nigra neurons and dopamine inputs to the striatum
• huntingtons diseases: dementia and disorder of personality
• Ballism: large movements of proximal limbs - damage to the nucleus via stroke
• Ataxia: lesions in the cerebellum - uncoordinated movements