Core Motor Systems

Question 1

motor system comprises of

Answer 1

pyramidal extrapyramidal vestibular and cerebellum

Question 2

motor system is responsible for

Answer 2

posture reflexes muscle tone and voluntary muscle movement

Question 3

pathway and neurons of motor system originates in

Answer 3

motor pathway originates in - brain and brainstem

motor neurons originate in - anterior horns of spinal cord and send axons via ventral roots

Question 4

motor tracts of spinal cord

Answer 4

pyramidal tracts - corticospinal corticobulbar tracts

extrapyramidal tracts - rubrospinal reticulospinal vestibulospinal tectospinal

Question 5

reflex arc

Answer 5

neural pathway that controls a reflex consists of receptor afferent synapses efferent and effector

Question 6

found at peripheral ends of afferent neurons

Answer 6

receptors

Question 7

which nuclear fibres have more fibres

Answer 7

nuclear chain have a higher number compared to nuclear bad

Question 8

gamma efferents are attached to

Answer 8

end of muscle spindle fibres

Question 9

can extrafusal fibres stimulate muscle spindle

Answer 9

no muscle spindle cannot be stimulated by whole skeletal movement because extrafusal fibres cause shortening rather than stretch

Question 10

dynamic rapid discharge from stretched muscle

Answer 10

nuclear bag

Question 11

static response

Answer 11

nuclear chain

Question 12

synapses within motor system occurs at

Answer 12

spinal cord

Question 13

mechanism of synapses within motor system

Answer 13

direct single synapse between primary afferent (1a) and the cell body efferent neuron (A alpha) with the help of neurotransmitter glutamate

Question 14

constitue 30% of all motor neuron in ventral roots of spinal cord

Answer 14

a gamma fibres

Question 15

a gamma fibres contract what fibres

Answer 15

ends of intrafusal fibers

Question 16

hypertonia of muscles is caused by

Answer 16

a gamma discharge is increased (UMNL)

Question 17

increased a gamma discharge leads to

Answer 17

spasticity and rigidity of muscles

Question 18

spasticity occurs in

Answer 18

hypertonia one group of muscles i.e. flexors but not extensors

Question 19

rigidity is present in

Answer 19

hypertonia in both groups of muscles agonists antagonist

Question 20

clasp knife hypertonia

Answer 20

resistant to passive stretch then resistance disappears

- sign of spasticity

Question 21

lead pipe hypertonia

Answer 21

resistant throughout movement

- sign of rigidity

Question 22

cog wheel

Answer 22

inconsistent rigidity

Question 23

hypotonia of muscles is caused

Answer 23

a gamma discharge is decreased (LMNL)

Question 24

increases a gamma discharge

Answer 24

pyramidal tract and cerebellum (facilitatory)

Question 25

decreases a gamma discharge

Answer 25

extrapyramidal tract (inhibitory)

Question 26

increases a gamma discharge and is associated with hyperreflexia

Answer 26

anxiety

Question 27

hoffmans sign

Answer 27

taping of third or fourth finger resulting in flexion of thumb for a positive sign

Question 28

difference between hoffmans sign and babinski sign

Answer 28

hoffman - fingers monosynaptic reflex | babinski - foot polysynaptic reflex

Question 29

cause of lmnl

Answer 29

decrease in a gamma discharge

Question 30

fasciculation is a sign of a gamma discharge

Answer 30

lmnl

Question 31

inverse stretch reflex

Answer 31

golgi tendon reflex

Question 32

habitual stimulation of receptors leads to

Answer 32

decrease in calcium and neurotransmitters

Question 33

decubitus ulcers

Answer 33

open skin wound sometimes known as a pressure ulcer, bed sore, or pressure sore. A decubitus ulcer forms where the pressure from body the body's weight presses the skin against a firm surface, such as a bed or wheelchair. Pressure cuts off the blood supply to the skin and injures tissue cells.

Question 34

autonomic dysreflexia

Answer 34

condition in which your involuntary nervous system overreacts to external or bodily stimuli. It's also known as autonomic hyperreflexia this reaction causes: a dangerous spike in blood pressure

Question 35

pyramidal system is composed of

Answer 35

``` corticospinal tracts ( ventral and lateral ) corticobulbar tracts ```

Question 36

concerned with fine skilled movement

Answer 36

lateral corticospinal neurons

Question 37

concerned movement of trunk and proximal movement

Answer 37

ventral corticospinal neurons

Question 38

concerned movement of neck face oral cavity and larynx

Answer 38

corticobulbar neurons

Question 39

damage to pyramidal system above decussation leads to

Answer 39

inability to perform voluntary movement on opposite side

Question 40

largest descending pathway in humans

Answer 40

corticospinal tracts

Question 41

corticospinal tracts that descends ipsilaterally supply

Answer 41

motor fibres only

Question 42

corticospinal tracts that decussate carry

Answer 42

sensory and motor fibres

Question 43

major motor system in non-mamamalian

Answer 43

extrapyramidal system

Question 44

extrapyramidal structures include

Answer 44

- basal ganglia - sub thalamic nucleus - substantia nigra - cerebellum - red nucleus

Question 45

extrapyramidal tracts that arise from brain stem and subcortical structures include

Answer 45

- rubrospinal tract - tectospinal tract - vestibulospinal tract - reticulospinal tract

Question 46

structures of basal ganglia include

Answer 46

- caudate nucleus - putamen - globus pallidus - sub thalamus - substantia nigra

Question 47

form corpus striatum

Answer 47

caudate and putamen

Question 48

form lenticular nucleus

Answer 48

globus pallidus and putamen

Question 49

two segments of globes pallidus

Answer 49

internal and external segment

Question 50

pigment and segments of substantial nigra

Answer 50

melanin and pars compacta and pars reticularis

Question 51

damage to this pathway causes parkinson syndrome

Answer 51

dopaminergic nigrostriatal pathway in subsntia nigra pars compacta

Question 52

how does substantial nigra inhibit thalamus and brainstem

Answer 52

by releasing GABA

Question 53

main afferent inputs into corpus striatum aka basal ganglia aka caudate and putamen

Answer 53

from cerebral cortex - excitatory input by releasing glutamate - and some interneurons release acth from substance nigra pars compacta - inhibitory input by releasing dopamine others from limbic system and brain stem

Question 54

main efferent outputs from corpus striatum

Answer 54

from globus pallidus - inhibitory out puts by releasing gaba from substantial nigra pars reticualris - receives inhibitory output from corpus striatum by gaba

Question 55

chorea

Answer 55

- damage to caudate - spontaneous uncontrolled movement that increases with emotion - hypotonia - results in less release of gaba - dopamine antagonist treatment haloperidol

Question 56

athetosis

Answer 56

- damage to globes pallidus - slow twisting movement - treatment anticholinergic drugs

Question 57

ballism

Answer 57

- damage to sub thalamic nucleus - violent crontractionc - hemiballius - hypotonic - treatment dopamine antagonist haloperidol phenothiazines

Question 58

deep cerebellar nuclei include

Answer 58

dentate nucleus globose nucleus emboliform nucleus fastiagl nucleus

Question 59

globose nuclei and emboli form nucleus form

Answer 59

interpostius nucleus

Question 60

cells of cerebellar

Answer 60

``` purkinje granular basket golgi stellate ```

Question 61

inhibitory cells of cerebellar

Answer 61

``` purkinje basket golgi stellate all release neurotranasmitter gaba ```

Question 62

excitatory cell of cerebellar

Answer 62

granular and releases glutamate

Question 63

layers of cerebellar cortex

Answer 63

three - superficial molecular layer - middle purkinje layer - deep granular layer

Question 64

contains stellate and basket inhibitory cells | also contains dendritic arbors of purkinje cells and parallel fibres from granular cells that may form synapses

Answer 64

superficial molecular layer

Question 65

contains purkinje cells

Answer 65

middle purkinje layer

Question 66

purkinje cells receive excitatory input from

Answer 66

- climbing fibres from inferior olivary nucleus in medulla | - parallel fibres from granular cells

Question 67

purkinje cells receive inhibitory input from

Answer 67

basket cells

Question 68

purkinje cells send inhibitory output to

Answer 68

deep cerebellar nuclei

Question 69

contains granular and golgi cells

Answer 69

deep granular layer

Question 70

most numerous neurons in brain

Answer 70

granular cells

Question 71

deep granular layer receives excitatory input from

Answer 71

- most fibres from pontine nucleus and inhibitory feedback from golgi cells