Locomotion and posture Flashcards Preview

Hugh's MD1 Neuro > Locomotion and posture > Flashcards

Flashcards in Locomotion and posture Deck (36):
1

What is meant by having a secure synapse?

Only one signal is required to active the post synaptic cell

1

What is the pattern of loss of innervation in UMN lesions of the face?

Loss of innervation to the bottom quadrant on the contralateral side

1

What is the difference between UM and LM lesion signs?

UMNL

Spastic weakness

Increased tone

Increased reflexes

Babinski sign positive

 

LMN

Flaccid weakness

Atropy

Decreased tone

Decreased reflexes

Negative babinski sign

Signs of deinnervation - fasciculations and fibrillations

2

Most of the input from the brain to local spinal cord motor neurons is via what?

Local interneurons

4

What is scanning speech due to?

Problems in the cerebellum

4

What are fasciculations?

Groups of muscles fibres activating spontaneously, probably due to signs for dying MNs/axons

5

Which tract has direct connections from the cortex to local motor neurons in the spinal cord?

The lateral corticospinal tract

6

What are some signs of faulty motor control?

- paralysis weakness
- stiffness
- increased reactivity
- ticks, twitches and jerks
- fibrillation and fasciculations
- loss of coordination and smoothness
- loss of the effectiveness of movements.
- speech problems. 

7

What is Henneman's size principle?

In the recruitment of motor units for a movement, the smallest, least fatigable are recruited first while the biggest are recruited last

8

What is expressive aphasia?

Inability to formulate words despite being able to comprehend them, due to disconnection between the language and motor areas required for speech

9

The colliculospinal tract is for what?

Orientating reflexes

Visual looming - eg falling

9

Why are there different patterns of innervation loss between upper and lower motor neuron injuries of the facial nerve?

Because the upper half of the face receives innervation from both sides of the face

10

T/F Lateral motor tracts control more lateral motor neurons

True

12

In which part of muscular control do you find very secure synapses?

Peripheral muscle synapses

13

What is the receptor at the neuromuscular cleft?

Nicotinic receptor

14

Motor control from the lateral vestibular nuclei is important for what?

Maintenance of posture

15

When does the motor cortex come into locomotor?

Initiating locomotion

Modulating pattern generation in response to obstacles 

16

What controls the initiation of swing in locomotion?

Feedback from receptors in extensor muscles 

eg extension is still maintained while there is feedback from golgi tendon organs that a load is present

18

What is the purpose of post junctional folds at the neuromusclar cleft?

Increase the SA for ACh and nicotinic receptors

19

What is anticipation?

Learned movement that compensates for reflexes

eg When catching a ball, the muscle involved will contract in preparation and help with the reflexes to together control movement required for catching

20

What are UMNs?

Neuronal systems that influence the lower motor neuron

22

What are signs of de-activation of muscle?

Fibrillations

Fasciculations

Atropy and degeneration

22

What are fibrillations?

Tiny contraction of sinlge muscle fibres due to hyperreactivity or increased AChr expression

23

Gait abnormalities are good clinical signs because?

They correspond to specific CNS disorders

24

What does a change from decorticate to decerebrate sign tell you?

The lesion is spreading downwards towards to the reticular formation

25

What is the difference between decorticate and decerebrate signs?

In decerebrate the lesion has spread down to disrupt the rubrospinal tract of the red nucleus (that causes flexion) therefore you get extension of both limbs

26

Why do babies exhibit positive Babinski sign before they've learnt to walk?

The brain is yet to exert influence on the spinal cord

27

What does a decerebrate sign looks like?

Upper and lower limbs extended

28

What does a decorticate sign look like?

Extension of lower limb and flexion of upper limb

30

Where are the locomotion pattern generators?

In the spinal cord

31

As a rule, the ventromedial tracts are for much?

Control of posture

32

What is an example of preparatory control of postural stability?

Activation of hip and shoulder on the contralateral side of a abducting leg to compensate for increased weight

33

What is the pattern of loss of innervation in LMN lesions of the face?

Loss of innervation of the whole ipsilateral side of the face

34

What is the neurotransmitter at the neuron muscular cleft?

ACh

35

What does scanning speech sound like?

Slow, forceful, lacks intonation

36

The lateral corticospinal tract is for what type of movement?

It innervates lateral muscles - therefore mainly voluntary skilled movement