Motor System Lesions

Question 1

major sources of motor disruption

Answer 1

• peripheral motor connections
• cortical connections
• basal ganglia
• cerebellum

Question 2

Motor disorders involving the peripheral nervous system can involve disruptions of

Answer 2

• The neuromuscular junction
• peripheral nerves
• spinal nerve roots

Question 3

produce motor disruption by altering the connections between motor axons and muscle (neurotransmission)

Answer 3

Neuromuscular Junction Disease (NMJ)

Question 4

Neuromuscular Junction Disease (NMJ) involves

Answer 4

• motor axon
• the neurotransmitter (acetylcholine)
• neurotransmitter receptors on the muscle or the metabolism of the neurotransmitter

Question 5

autoantibodies are formed to acetylcholine receptors where the antibodies can block neuromuscular transmission

Answer 5

Myasthenia Gravis

Question 6

Can have weakness mainly in skeletal muscles innervated by cranial nerves with ocular weakness and bilateral ptosis

Answer 6

Myasthenia Gravis

Question 7

treatment for Myasthenia Gravis

Answer 7

cholinesterase inhibitors, which prevent the breakdown of acetylcholine after it is released by the nerve

Question 8

one of a group of toxins from a bacterium (clostridium botulinum, one type of food poisoning) that irreversibly blocks the release of acetylcholine by binding to the presynaptic membrane in neuromuscular junctions and at preganglionic autonomic terminals

Answer 8

Botulinum Toxin

Question 9

Nerve terminals fully disrupted by botulinum toxin must regrow or “sprout” locally for function to be restored

Answer 9

Botulinum Toxin

Question 10

with Botulinum Toxin what type of muscles are affected?

Answer 10

Both smooth and skeletal muscle

Question 11

with Botulinum Toxin you typically have weakness in

Answer 11

cranial nerve muscles and then in the limbs

Question 12

dry mouth, abdominal cramping, vomiting and diarrhea because of an absence of peristalsis are symptoms of what

Answer 12

autonomic symptoms of Botulinum Toxin

Question 13

Peripheral Nerve [Lesions- axons] can include damage to

Answer 13

• Dorsal roots
• Ventral roots
• And /or a spinal nerve

Question 14

deficits usually associated with a particular spinal segment or restricted to particular muscles/groups that can be attributed to the functions of a single nerve

Answer 14

Mononeuropathy

Question 15

in Mononeuropathy sensory loss is often used to identify what?

Answer 15

the nerve or root involved

Question 16

Flaccid paralysis followed relatively rapidly (weeks to months) by atrophy of the muscle is what?

Answer 16

Peripheral Motor System Lesions

Question 17

Hypotonia is what?

Answer 17

decreased muscle tone

Question 18

Hyporeflexia, areflexia is what?

Answer 18

weakening or absence of tendon reflexes

Question 19

Fibrillations or fasciculations of motor units as a result of denervation due to what?

Answer 19

Peripheral Motor System Lesions

Question 20

Disseminated

Answer 20

result from metabolic diseases

Question 21

Onset of what may be very slow and almost unnoticed (e.g. diabetes) or very rapid in some autoimmune neuropathies

Answer 21

Disseminated

Question 22

typical pattern is the “stocking” or “glove” like deficits in limbs that usually involve both motor and sensory problems in what

Answer 22

Disseminated

Question 23

isolated sensory or motor deficits is the compression of nerve roots as they leave the spinal cord

Answer 23

Nerve Compression at Spinal Roots - Radiculopathies

Question 24

• Compressions of sensory roots are usually painful, or produce paresthesias
• Motor roots can also be selectively disrupted resulting in weakness of muscles innervated by the spinal root

Answer 24

Nerve Compression at Spinal Roots - Radiculopathies

Question 25

symptoms of what type of lesion can be more complex and dependent upon the structure(s) damaged

Answer 25

Central Nervous System Motor Lesions

Question 26

- paralysis or paresis with muscles that are initially weak and flaccid followed by (Spasticity, Hypertonia, Hyperreflexia, altered cutaneous reflexes including the Babinski sign (or Hoffmann sign) , and Clonus and a clasp knife response may also be present) - Basal ganglia disturbances - Cerebellar disturbances

Answer 26

Central Nervous System Motor Lesions

Question 27

what lesion can produce upper motor neuron signs to varying degrees

Answer 27

Primary Motor Cortex Lesions

Question 28

what lesion causes effects on movement

Answer 28

Primary Motor Cortex Lesions

Question 29

lesions restricted to what produce disruptions of fine motor control such as finger movements

Answer 29

Primary Motor Cortex Lesions

Question 30

typical upper motor neuron signs from more severe injuries result in

Answer 30

part from the loss of cortical influences (often inhibitory) on tracks originating in the brainstem

Question 31

posturing or decorticate rigidity in humans results from brainstem sections above the superior colliculus that leaves the red nucleus and the influence of the rubrospinal tracts in place

Answer 31

Decortication

Question 32

the upper limb is flexed, while the lower limbs remain extended

Answer 32

Decortication

Question 33

produce a higher flexor tone in the upper limb (flexor activation is generally stronger than extensor)

Answer 33

Decortication

Question 34

​​what results in unopposed extensor muscle activity in all four limbs or decerebrate rigidity

Answer 34

Brainstem Spinal Influences Lesions

Question 35

when there is a Brainstem Spinal Influences Lesions what does it interrupt?

Answer 35

the lower midbrain interrupts the corticospinal and rubrospinal tracts

Question 36

what produces motor processing problems

Answer 36

motor cortical areas outside of primary motor cortex

Question 37

what is expressed as the inability to use the affected body part to perform voluntary or learned movements in spite of the lack of spasticity, paralysis or altered tone in the muscles

Answer 37

Apraxias

Question 38

Lesions of premotor cortex usually result in

Answer 38

apraxias

Question 39

Lesions of premotor cortex can affect

Answer 39

the ability to coordinate action on the two sides of the body, particularly in relation to learned movements

Question 40

integration and processing of important feedback information from muscle spindles and other sensory receptors that can be used to guide motor activities

Answer 40

feedback control in the cerebellum

Question 41

information to motor areas of cortex, not only to monitor and correct motions in progress but what

Answer 41

provide appropriate cues for subsequent actions

Question 42

precise coordination of movement rather than the initiation or control of movement is what

Answer 42

Cerebellar Dysfunction- Motor Disruption

Question 43

when there is a motor disruption what aspect of movements can be affected?

Answer 43

posture, gait, speech, and eye movements

Question 44

when posture, gait, speech, and eye movements are affected what region is the damage in?

Answer 44

cerebellar region

Question 45

tests show a lack of coordination of motor tasks, but not a problem with initiating and actually performing the movement

Answer 45

Resembles a sobriety test

Question 46

poor walking, unsteady

Answer 46

Ataxia (cerebellar)

Question 47

past point sign-unable to gage distance in motor tasks

Answer 47

Dysmetria

Question 48

unable to perform rapid alternating movements

Answer 48

dysdiadochokinesia

Question 49

oscillations during directed movement

Answer 49

Intention tremor

Question 50

a slow / thick speech

Answer 50

scanning speech

Question 51

Lesions of the cerebellum will disrupt the feedback to the what

Answer 51

motor cortex on the opposite side of the midline

Question 52

when there is a lesion in the cerebellum the symptoms are?

Answer 52

on the same side of the midline (ipsilateral) to the lesion site

Question 53

what lesion result in a variety of movement disorders that include involuntary movements (dyskinesias) to rigidly contracted muscles (dystonias)

Answer 53

Basal Ganglia Lesions

Question 54

what diseas is a major hallmarks of the basal ganglia disease are involuntary movements and alteration of muscle tone

Answer 54

Parkinson disease

Question 55

arise from lesions to a balanced system of excitatory and inhibitory influences on movement

Answer 55

extrapyramidal symptoms

Question 56

what disorder is characterized by a paucity of movement and rigidity- increased muscle tone throughout the range of motion that does not vary with passive acceleration

Answer 56

Hyperkinetic disorders

Question 57

what is the most common hypokinetic disorder?

Answer 57

Parkinson's Disease

Question 58

Parkinson disease will begins what?

Answer 58

unilaterally and slowly progress to the opposite side

Question 59

Parkinson can effect what?

Answer 59

postural instability may result in total disability

Question 60

hereditary disorder with an trinucleotide expansion on chromosome 4

Answer 60

Huntington Chorea

Question 61

onset of Huntington Chorea is?

Answer 61

around age 40

Question 62

movements on one side of the body and hypotonus associated with a unilateral (contralateral ) destruction of the subthalamic nucleus is what?

Answer 62

Hemiballismus

Question 63

what creates and imbalance in basal ganglia circuitry that results in loss of inhibition

Answer 63

Hemiballismus

Question 64

slow loss (possibly decades) of neurons in the substantia nigra pars compacta (pigmented, dopaminergic)

Answer 64

Parkinsonism (paralysis agitans)

Question 65

what is a Hypokinetic Movement disorder?

Answer 65

- lack of movement - reduced amplitude of movements - slow movement - rigidity

Question 66

sustained muscle contractions that may be focal or broadly distributed

Answer 66

Dystonia

Question 67

if dystonia is drug induced dystonias it is usually from?

Answer 67

dopaminergic agents

Question 68

what percent is responsive to L-Dopa

Answer 68

5-10%

Question 69

slow writhing movements-generally associated with broad pathological changes in cortex and neostriatum

Answer 69

Athetoid Movements

Question 70

an immaturity of the organization of movement

Answer 70

Developmental Coordination Disorder (Developmental Dyspraxia)

Question 71

Developmental Coordination Disorder (Developmental Dyspraxia) affects ___ of people an ___ severely

Answer 71

10%; 2%

Question 72

- not exclusively motor - poor short term memory - cognitive problems - difficulty with language skills

Answer 72

Developmental Coordination Disorder (Developmental Dyspraxia)