Motor control Flashcards Preview

Building the nervous system > Motor control > Flashcards

Flashcards in Motor control Deck (14):
1

What is the highest level of motor control and how does it project to the middle layer

Primary motor cortex and projects to the brainstem via the corticospinal tract

2

What is the middle level of motor control

Brainstem - lateral descending system controlling the distal limbs - important for goal directed movement of the hand and arms

3

What is the lowest level of motor control

Spinal cord - Contains neuronal circuits that mediate automatisms such as walking
simplest reflex is mono-synaptic sensory neuron and motor neuron: monosynaptic tendon jerk reflex
Most reflexes are polysynaptic with interneurons

4

What happens if the primary motor cortex is stimulated with an electrode

Only a twitch is seen in the relevant response - no complicated movements

5

What is the role of the basl ganglia and cerebellum

Receive info from many different axons of the cortex - project back to the cortex via the thalamus
Aware of the situation the body is in and monitor commands going to the muscles
If these signals are inappropriate - steps in and calculates correction signals - send to motor cortex for approval before being sent to the muscles

6

What is the difference between the basal ganglia and cerebellar motor control

Basal ganglia loop only feeds back to the motor cortex - subcortical loop
Cerebellum mainly feeds to motor cortex but can send signals down to the brainstem/spinal cord/muscles in emergency situations

7

What does stimulation of one side of the frontal lobe produce

Response seen on contralateral side of the body - decussation

8

How were motor maps formed

Correlated with observations of effects of lesions

9

What is Brodmann's area 4

Area in which the lowest intensity of stimulation elicited movement

10

Where is Brodmann's area located

Just before the central culcus

11

How does Brodman's area 4 show orderly arrangement

Along the gyrus body parts are innervated for in a descending order

12

Why are finger areas widespread

In the event of motor cortex damage - reduces the chance of complete loss of a single digits function - instead all of the digits function becomes slightly worse

13

What are the motor cortex's first neurons called

Upper motor neurons

14

What are the motor cortex's upper motor neurons projections

Carry the motor command down the brain/brainstem/spinal cord - eventually synapse with the lower motor neurons via an interneuron