Motor Control (Part 2)

Question 1

What is benign paroxysmal positional vertigo?

Answer 1

Sudden sensation of spinning, usually when moving the head (most common cause of vertigo)

Question 2

What technique is commonly used to cure vertigo?

Answer 2

Epley’s maneuver

Question 3

How does the Epley’s maneuver cure vertigo?

Answer 3

The free floating particles from the affected semicircular canals are relocated using gravity back into the utricle where they can no longer stimulate the cupula

Question 4

What is the success rate of the Epley’s maneuver?

Answer 4

90-95%

Question 5

One’s sense of being upright is a combination of what two things?

Answer 5

Visual and vestibular information

Question 6

What triggers vestibular reflexes?

Answer 6

Changes in the position of the head

Question 7

What triggers neck reflexes?

Answer 7

Tilting or turning of the neck

Question 8

Which major mechanism of postural adjustments are associated with the “feed forward” idea?

Answer 8

Anticipatory

Question 9

Which major mechanism of postural adjustments are associated with the “feedback” idea?

Answer 9

Compensatory

Question 10

Which major mechanism of postural adjustments are modified by experience and improves with practice?

Answer 10

Anticipatory

Question 11

Which major mechanism of postural adjustments are evoked by sensory events following loss of balance?

Answer 11

Compensatory

Question 12

Which major mechanism of postural adjustments is faster?

Answer 12

Anticipatory

Question 13

Which major mechanism of postural adjustments is slower?

Answer 13

Compensatory

Question 14

Sensory input for postural mechanisms comes from what four things?

Answer 14

Cutaneous receptors from the skin (especially feet), proprioceptors from joints and muscles, vestibular signals (head motion), and visual signals

Question 15

Which two areas of input for postural mechanisms have longer latency effects?

Answer 15

Vestibular and visual signals

Question 16

Which area of input for postural mechanisms has a short latency period?

Answer 16

Proprioceptors from joints and muscles (70-100ms)

Question 17

In what sequence does contraction of muscles to maintain balance occur?

Answer 17

Distal to proximal

Question 18

What is the order of muscular contraction for forward sway in chronological order?

Answer 18

Gastrocnemius, hamstring, paraspinals

Question 19

What is the order of muscular contraction for backward sway in chronological order?

Answer 19

Anterior tibs, quadriceps, abdominal muscles

Question 20

When rotating or laterally bending, which extensors and flexors are facilitated?

Answer 20

Ipsilateral extensors, contralateral flexors

Question 21

Which two basal ganglia make up the striatum?

Answer 21

Caudate and putamen

Question 22

What are the three input nuclei of the basal ganglia?

Answer 22

Caudate, putamen, and nucleus accumbens

Question 23

What are the four output nuclei of the basal ganglia?

Answer 23

Globus pallidus (external segment), subthalamic nucleus, substantia nigra, and ventral tegmental area

Question 24

What are the four principle nuclei of the basal ganglia?

Answer 24

Striatum (caudate and putamen), globus pallidus (internal and external), substantial nigra, and subthalamic nucleus

Question 25

Do the basal ganglia have direct input or output connections with the spinal cord?

Answer 25

NO

Question 26

What mediates the motor functions of the basal ganglia?

Answer 26

Motor areas of the cortex

Question 27

Disorders involving the basal ganglia can have what three types of motor disturbances?

Answer 27

Tremor & other involuntary moments; changes in posture & muscle tone; poverty & slowness of movement

Question 28

Through what structure do both major circuits of the basal ganglia relay their information?

Answer 28

Thalamus

Question 29

The caudate nucleus plays a major role in what part of motor activity?

Answer 29

Cognitive control

Question 30

The putamen circuit focuses on what aspect of movement?

Answer 30

Subconcious execution of learned patterns

Question 31

What are the two major circuits of the basal ganglia?

Answer 31

Caudate and putamen circuits

Question 32

Where is the lesion located in athetosis?

Answer 32

Globus pallidus

Question 33

What is athetosis?

Answer 33

Spontaneous and continuous writhing movements

Question 34

Where is the lesion located in hemiballismus?

Answer 34

Subthalamus

Question 35

What is hemiballismus?

Answer 35

Sudden violent flailing moments of a limb

Question 36

Where are the multiple small lesions located with chorea?

Answer 36

Putamen

Question 37

What is chorea?

Answer 37

Flicking movements in hands, face, etc.

Question 38

Where is the lesion located with rigidity, akinesia, and resting tremors such as those found with Parkinson's Disease?

Answer 38

Substantia nigra

Question 39

What is the reentrance loop cycle for the basal ganglia beginning in the neocortex?

Answer 39

Neocortex to basal ganglia to thalamus to frontal cortex

Question 40

What is the reentrance loop cycle for the basal ganglia beginning in the external globus pallidus?

Answer 40

Globus pallidus to subthalamic nucleus to both internal and external globus pallidus

Question 41

What is the reentrance loop cycle for the basal ganglia beginning in the striatum involving neurotransmitters?

Answer 41

Striatum (GABA) to substantia nigra (dopamine) to striatum

Question 42

What is the reentrance loop cycle for the basal ganglia beginning in the striatum?

Answer 42

Striatum to globus pallidus to centromedial nucleus of thalamus to straitum

Question 43

Which three reentrance loops of the basal ganglia are subcortical?

Answer 43

All but the one beginning in the neocortex

Question 44

What does cerebellum mean?

Answer 44

"little brain"

Question 45

The cerebellum makes up what percentage of the weight of the total brain?

Answer 45

10%

Question 46

About what percentage of neurons of the brain lie in the cerebellum?

Answer 46

Greater than 50%

Question 47

What is the function of the cerebellum in regards to movement and posture?

Answer 47

Adjusts the output of the major descending motor systems

Question 48

What happens to sensation and muscle strength if the cerebellum is completely destroyed?

Answer 48

No sensory impairment and no loss in muscle strength

Question 49

What parts of the cerebellum makes up the vestibulocerebellum?

Answer 49

Flocculonodular

Question 50

What parts of the cerebellum make up the spinocerebellum?

Answer 50

Vermis and intermediate

Question 51

What parts of the cerebellum make up the cerebrocerebellum?

Answer 51

Lateral zone

Question 52

What is the function of the vestibulocerebellum?

Answer 52

Governs eye movement and body equilibrium

Question 53

What is the function of the spinocerebellum?

Answer 53

Major role in movement, influencing descending motor systems

Question 54

What is the function of the cerebrocerebellum?

Answer 54

Planning and initiation of movement and extractor prediction, mental rehearsal of complex motor actions, conscious assessment of movement errors

Question 55

What is the input and output of the vestibulocerebellum?

Answer 55

Vestibular nuclei, vestibular nuclei

Question 56

What is the input and output of the spinocerebellum?

Answer 56

Periphery and spinal cord, cortex

Question 57

What is the input and output of the cerebrocerebellum?

Answer 57

Pontine nucleus, pre and motor cortexes

Question 58

Do lesions of the cerebellum yield ipsilateral or contralateral effects?

Answer 58

Ipsilateral

Question 59

What is the major inhibitory cell in the cerebellar cortex?

Answer 59

Purkinje cells

Question 60

Where do Purkinje cells project to?

Answer 60

Deep cerebellar nuclei

Question 61

What is the ratio of climbing fibers to Purkinje cells?

Answer 61

1:1

Question 62

What is the ratio between mossy fibers and Purkinje cells?

Answer 62

1 mossy fiber excites hundreds to thousands of Pukinje cells

Question 63

What is the climbing fiber input?

Answer 63

Inferior olivary nucleus

Question 64

What is the mossy fiber input?

Answer 64

Everywhere else except the inferior olivary nucleus

Question 65

A complex action potential generated by a Purkinje cell involves which type of fiber?

Answer 65

Climbing

Question 66

A simple action potential generated by a Purkinje cell involves which type of fiber?

Answer 66

Mossy