3. Motor Paralysis

Question 0

Within a few days after interruption of a motor nerve, the individual denervated muscle fibers begin to contract spontaneously. This isolated activity is called __________ & it cannot be seen through intact skin, but can be recorded as a small, repetitive, short-duration potential in EMG.

Answer 0

Fibrillation

Question 1

When a motor neuron becomes diseased, it may manifest increased irritability and all the muscle fibers that it controls may discharge sporadically. The result of contraction of 1 or several such motor units is a visible twitch called __________ that appears in EMG as a large spontaneous muscle action potential.

Answer 1

Fasciculation

Question 2

Simultaneous/ sequential spontaneous contractions of multiple motor units cause a rippling of muscle known as __________

Answer 2

Myokimia

Question 3

These are large motor neurons of the anterior horn

Answer 3

Alpha motor neurons

Question 4

These are small anterior horn cells whose axons terminate on the small intrafusal muscle fibers within the spindles

Answer 4

Gamma motor neurons

Question 5

These motor neurons effect contraction of both spindle & nonspindle fibers

Answer 5

Beta motor neurons

Question 6

These are the main neurotransmitters of the descending corticospinal tract

Answer 6

Aspartate

Glutamate

Question 7

This is the neurotransmitter released by Renshaw cells, which are responsible for recurrent inhibition, and by interneurons that mediate reciprocal inhibition during reflex action

Answer 7

Glycine

Question 8

This serves as the inhibitory neurotransmitter of interneurons in posterior horns

Answer 8

GABA

Question 9

These are released by primary afferent terminals & interneurons & act specifically on excitatory amino acid receptors

Answer 9

L-glutamate

L-aspartate

Question 10

This is the only direct long-fiber connection between the cerebral cortex & the spinal cord

Answer 10

Corticospinal tract

Question 11

The primary motor cortex/ precentral gyrus corresponds to Brodmann area ___

Answer 11

4

Question 12

The primary somatosensory cortex corresponds to Brodmann areas __________

Answer 12

3, 1, 2

Question 14

What is the essential feature of spasticity?

Answer 14

A velocity-dependent increase in resistance of muscles to a passive stretch stimulus

Question 15

If the muscles are briskly stretched, the limb moves freely for a very short distance, beyond which there is an abrupt catch and then a rapidly increasing muscular resistance up to a point; then, as passive extension of the arm or flexion of the leg continues, the resistance melts away. This sequence is called __________

Answer 15

Clasp-knife phenomenon

Question 16

What is the most sensitive indication of an UMN lesion?

Answer 16

Babinski sign

Question 17

This is a series of rhythmic involuntary muscular contractions occurring at 5-7 Hz in response to an abruptly applied and sustained stretch stimulus

Answer 17

Clonus

Question 18

This is a state in which an attentive patient loses the ability to execute previously learned activities in the absence of weakness, ataxia, sensory loss, or extrapyramidal derangement that would be adequate to explain the deficit

Answer 18

Apraxia

Question 19

Failure to conceive or formulate an action, either spontaneously or on command; characterized by difficulty in “what to do”

Answer 19

Ideational apraxia

Question 20

The patient may know & remember the planned action but because these areas or their connections are interrupted, he cannot actually execute it with either hand; a block in “how to do”

Answer 20

Ideomotor apraxia

Question 21

An ill-defined clumsiness & maladroitness that is the result of an inability to connect or isolate individual movements of the hand & arm

Answer 21

Limb-kinetic apraxia

Question 22

Which lobe embodies the property of praxis?

Answer 22

Dominant parietal lobe

Question 23

The most common of all apraxias in practice, characterized as inability to carry out facial movements on command

Answer 23

Oral-buccal-lingual apraxia

Question 24

What is the most common cause of monoplegia without muscular atrophy?

Answer 24

A cerebral vascular lesion

Question 25

This is the most common form of paralysis

Answer 25

Hemiplegia

Question 26

What is the most common cause of acute paraplegia or quadriplegia?

Answer 26

Spinal cord trauma

Question 27

What are the identifying characteristics of spasticity?

Answer 27

A predilection for involvement of certain muscle groups
A specific pattern of response of muscles to passive stretch
Manifest exaggeration of tendon reflexes