Motor

Question 1

Learnt threat =

Answer 1

cortex and limbic system

Question 2

Loom =

Answer 2

sensorimotor midbrain

Question 3

Pain=

Answer 3

SPinal cord

Question 4

How do muscles contract

Answer 4

The Myosin cross bridge
Calcium
Actin
AtP

Question 5

The motor unit is

Answer 5

a single alpha + all the muscle fibres it innervates

Question 6

The motor pool is

Answer 6

All the lower motor neurons which innervate a single muscle

Question 7

Dorsal route

Answer 7

Back.

Sensory, input ascending. unipolar, afferent. CNS spinal cord.

Question 8

VEntral route

Answer 8

Front

Motor, descending. Multipolar, efferent. Muscles.

Question 9

Proprioception is

Answer 9

Sensing in muscles

Question 10

What detects tension in a muscle

Answer 10

Golgi tendons- in the tendon, signals to spinal cord to make adjustments.

Question 11

What detects strecth in a muscle

Answer 11

Muscle spindles- wrap around the intrafusal, innervated by gamma (seperately to detect stretch)

Question 12

Control of muscle force?

Answer 12

1. Level of control - little force= muscle fibres which recruit fewer fibres.
2. Strength
   The size principle- recruits smallest first.

Question 13

How many layers or the motor cortex

Answer 13

6

Question 14

Where do the projections originate

Answer 14

motor cortex pyramidal cells

Question 15

where are the cell bodies located

Answer 15

grey matter of the cortex

Question 16

Cortical projections innervate…

Answer 16

contralateral motor units.

Question 17

The basal ganglia

Answer 17

Group of nuclei deep within the cerebral hemispheres.
motor control
Receives excitatory input from cortex- GLU
Outputs via thalamus
Output is inhibitory - GABA
The selection problem. Centralised selection.
Recurrent reciprocal inhibition.

• PArkinsons disease
• Huntingtons disease
• Tourettes
• TArdire Dyskinesia
• Hemiballismus

Question 18

The cerebellum

Answer 18

Conains half of the CNS neurons
INtention tremor, Dysarthia, jerky unco-ordinated.
Computes motor errors.
Excitatory output.

Question 19

The dorsolateral corticospinal tract?

Answer 19

Betz cells- Extremely large pyramidal cells of the motor cortex
Synapse on the medullary pyramid- contrlaterally to the distal muscles of the hands.

Question 20

The dorsolateral corticorubrospinal tract

Answer 20

synapses on the red nucleus. - distal muscles of arms and legs.
contralateral.

Question 21

Ventromedial corticospinal tract

Answer 21

Ipsilaterally. Motor.

Proximal.

Question 22

Ventromedial cortico- brainstem spinal tract

Answer 22

ipsilaterally

1. tectum
2. the vestibular nucleus
3. the reticular formation
4. the motor nucleus of the cranial nerves which control the muscles

Question 23

where are betz cells found?

Answer 23

they are extremely large pyramidal cells of the primary motor cortex.

Question 24

what is recurrent collateral inhibition

Answer 24

distributes the work between different motor neurons of the muscles motor pool

Question 25

what cells are recurrent collateral inhibition mediated by

Answer 25

renshaw cells