Neuro Quiz 7 Rev 1

Front 1

Dynamic spindle cell

Back 1

APs are produced during stretching regardless of length, the central sensory portion gets elongated and APs are produced at amplitude to the rate of stretching

Front 2

Static spindle cell

Back 2

Respond to length of spindle center and APs are proportional to length of spindle with increase length leading to high AP frequency

Front 3

The ends of spindle cells are fixed points but can only move by contraction of?

Back 3

extrafusal fibers that being the skeletal muscles.

Front 4

If the ends of spindle cells are considered fixed then if intrafusal fibers contract what happens?

Back 4

the center sensory portion gets stretched because the upper and lower portions shorten which produces sensory APs to show they’ve been stretched

Front 5

Spindle Afferent fibers synapse directly to Alpha motor neurons which control what muscle fibers?

Back 5

extrafusal

Front 6

In alpha motor neurons what sends axons to the extrafusal fibers of skeletal muscle?

Back 6

Anterior horn cells

Front 7

Another way to stimulate contraction with an alpha motor neuron you have an afferent from spindle going to the DRG to the dorsal horn of spinal cord to Laminae to anterior horn of dark matter finally synapsing on the alpha motor neuron. What does this do?

Back 7

Afferent processes will stimulate the alpha motor neuron causing extrafusal muscles to contract and the muscle shortens and the sensory portion is unstretched at the point because ends come close together being 5 percent of the length of the muscle resulting in less APs from spindle

Front 8

If you make an intrafusal muscle contractile muscle contract what controls striated muscle?

Back 8

Gamma motor neurons are for striated muscle

Front 9

If you activate a gamma motor neuron what happens?

Back 9

contractile portion of spindle contracts which stretches sensory portion stimulating the afferent portion which stimulates alpha motor neurons sending APs back to muscle fibers stimulate extrafusal muscle fibers to contract

Front 10

In regards to voluntary movement what does the gamma motor neuron do?

Back 10

they provide additional stimulation for muscle contraction providing a feedback on how much contraction and stimulating the contractile part of the spindle

Front 11

What neuron activates the spindle and has the ability to stop?

Back 11

gamma motor neuron (catching a brick with your hand the motion would continue to your face without it)

Front 12

What is the main function of the spindle?

Back 12

provide negative feedback of the muscle length

Front 13

When a tendon is stretched golgi tendons organs send?

Back 13

afferents to the spinal cord which are inhibitory to alpha motor neurons

Front 14

Golgi tendons tell the muscle to?

Back 14

not contract so much

Front 15

Afferents from the golgi tendon go back to the spinal cord via what neuron that synapses on the alpha motor neuron?

Back 15

interneuron

Front 16

The inhibitory signal that is provided by golgi tendons do what?

Back 16

provide neg feedback of muscle tension providing more control over muscles so you don’t crush an egg and the spindle provide negative feedback about length.

Front 17

What is the claspknife reflex?

Back 17

when you someone bends your arm back extensor muscle resists initially golgi tendon organs slowly inhibit alpha motor neurons and when there’s more inhibition and stimulation the muscle stops resisting and relaxes

Front 18

Basal nuclei are located?

Back 18

down towards the base of the brain and if damaged they produce positive symptoms

Front 19

CST (corticospinal tract) sends axons down the spinal cord and collateral branches do exist and CST also communicates with?

Back 19

Basal nuclei pathways such as Striatum that has a two way communication with substant nigra and it also comm with globus pallidus which has 2 way comm with subthalamic nucl.

Front 20

Damage to globus pallidus causes?

Back 20

athetosis twisting movement of the body.

Front 21

Damage to subthalamic nuclei causes?

Back 21

Ballistic large amplitude movement

Front 22

Damage to striatum may cause?

Back 22

Choreas little flicking movements

Front 23

What happens in Parkinsons?

Back 23

something happens to interfere with substantia nigra’s ability to make dopamine

Front 24

Below are 6 characteristics of Parkinson’s Disease: stooped posture/slow movements bradykinesia/ Feet aren’t lifted (shuffling gait) / constantly tremoring with pill rolling movements with hands / tremor of mandible masseter twitches / soft speech

Back 24

Migrographia (small handwriting) / if you push them backwards they won’t regain themselves so they keep moving backwards / getting up from a chair and freezing in position cannot initiate movement locked body / mask like face / all of these go away when sleeping.

Front 25

How do you treat Parkinson’s?

Back 25

replace dopamine but it is charged and can’t cross BBB but precursor to dopamine DOPA can but you need to give an inhibitor transaminase in the periphery as well to prevent DOPA becoming aminated. Dop decarboxylase is in the Brain so converts to Dopamine

Front 26

Dopamine is terminated during reuptake from synaptic space. If a drug resembles Dopamine to this transport system the drug will also be reuptaken by neurons. What are the two stages of reuptake?

Back 26

Reuptake 1. Cytoplasm and Reuptake 2. Vesicles. Enzymes in the cytoplasm MAO (monoamineoxidase) destroys dopamine

Front 27

In treating Parkinson’s you can potentially eliminate the output from the basal nuclei by cutting the pathway from globus pallidus to?

Back 27

the thalamus which eliminates positive symptoms however negative symptoms (mask-like face) are not removed.

Front 28

The location of the spindle cells are where?

Back 28

In between skeletal muscle fibers

Front 29

Regular muscle fibers are referred to as extrafusal fibers and the spindles are referred to as?

Back 29

Intrafusal fibers

Front 30

If you stretch a bicep muscle by straightening your arm the whole muscle gets longer and the spindles are elongated also and will be stretched by how much?

Back 30

1/20th more as well

Front 31

What are detectors of muscle elongation?

Back 31

spindle cells

Front 32

If you stimulate gamma motor neurons in the spinal cord they excite the contracting portions the upper and lower portions of a spindle cell which?

Back 32

stretches the middle sensory portion sending Aferent APs into the spinal cord which excite alpha motor neurons in the same muscle sending APs back to the same muscle fiber and the whole muscle shortens.

Front 33

What are the 2 ways we can excite voluntary muscle to contract?

Back 33

excite alpha motor neurons which directly causes extrafusal muscles to contract and we can also excite the gamma motor neurons which gets the fibers to contract via spindle cells

Front 34

When the physician hits your knee with a hammer what is he doing?

Back 34

he’s stretching the tendon and it indents a bit and stretches the muscle exciting the spindle sending Affer APs to the muscle of the neuron causing the muscle to contract and the leg kicks. Myotatic reflex

Front 35

Renshaw Cell

Back 35

essentially forces alpha motor neurons to rest before it fires again it acts as an IPSP.

Front 36

Clostridium Tetani toxin does what?

Back 36

blocks the release of glycine from renshaw cells so the whole regulation by the renshaw cells is blocked so no smooth sharing of the workload. You get spasms.

Front 37

LMN are also known as?

Back 37

alpha motor neurons

Front 38

If you recently injured an alpha motor neuron/LMN what happens?

Back 38

O membrane potential APs will fire stimulating muscle fibers at different frequencies until it eventually stops. This is fasciculation.

Front 39

What the membrane potential typically in alpha motor neuron axon?

Back 39

-80mV

Front 40

Totally useless independent frequency muscle contractions are known as?

Back 40

fasciculations caused by a damaged alpha motor neuron.

Front 41

UMN damage leads to?

Back 41

a temporary period of paralysis and most APs sent down are inhibitory rather that excitatory but the reason is unclear. Leads to temp. flaccid paralysis and hyperreflexia.

Front 42

When an UMN is injured there are also primitive reflexes that arise such as?

Back 42

Grasp reflex (hyperflexia) (touch palm and hand clasps) Sole of the foot where toes spread and try to dorsiflect. These reflexes are gone after by the time you’re 6 months-12months old.

Front 43

Toes that are plantarflex when touching the sole of the foot is a sign of?

Back 43

Normal reaction.

Front 44

In a person who has an UMN lesion that is more than a few weeks old touch the sole of the foot and the toes will spread and if possible dorsiflex. This is what?

Back 44

A Babinski reflex

Front 45

Positive Babinski sign is?

Back 45

Toes in dorsiflex

Front 46

LMN injury you get?

Back 46

fasciculation and then complete paralysis

Front 47

MC and Basal ganglia affect what side of the body?

Back 47

contralateral side

Front 48

Striatum is comprised of?

Back 48

caudate nucleus and putamen

Front 49

Ballisms is an example of what kind of damage?

Back 49

damage to the basal nuclei or more specifically subthalamic nuclei

Front 50

What Positive symptoms are shown with damage to basal nuclei?

Back 50

Ballisms, Choreas, Athetosis.

Front 51

What Negative symptoms are shown with damage to the basal nuclei?

Back 51

Bradykinesia (slow and have a problem starting to move) and lack of facial expression (mask-like face)

Front 52

What are the positive symptoms of PD?

Back 52

(Pill rolling tremor)(Mandibular Tremor)(difficulty swallowing)(stooped posture with arms flexed)(shuffling and not lifting feet)(slow movement Bradykinesia)(mask-like face)(can’t catch up with their center of gravity)

Front 53

PD is caused by?

Back 53

damage to the substantia nigras neurons

Front 54

MPTP

Back 54

is related to ecstasy and can cross the BB barrier and it looks like dopamine which is usually subject to MAO, but in this case converts to MPP+ which is toxic and kills the neurons. So then they had severe Parkinsons Disease

Front 55

People with severe parkinsons have problems with?

Back 55

initiating movements. They might start to get out of a chair and pause for a minute or two standing upright before he gets the instruction from PMC to the alpha motor neurons of the leg.

Front 56

What are the two kinds of information the cerebellum is receiving?

Back 56

Dorsal column information including proprioceptors (Sensory input) and motor commands coming out of the motor cortex.

Front 57

What does the neocerebellum do?

Back 57

Involved in the new stuff such as learning new patterns (hand movements and speech very fine motor control – fingers and thumbs)

Front 58

What does the spinocerebellum do?

Back 58

deals with posture and gait (walking)

Front 59

What does the vermis and floccula nodulus deal with?

Back 59

the vestibular system balance and adjustments for movment

Front 60

The left cerebellum gets inputs from the Right motor cortex and sensory input from what side of the body?

Back 60

the left side of the body

Front 61

A neocerebellar lesion in the right side of the cerebellum would lead to?

Back 61

decomposition of movement on the right side of the body

Front 62

What part of the cerebellum helps with setting up patterned movements?

Back 62

Neocerebellum Ex. Tying your shoe when you’re six suddenly stores the pattern

Front 63

When you can’t set up patterned movements due to a lesion of the neocerebellum this is referred to as?

Back 63

disdiadochokinesia and if you can’t do it at all that is adiadochokinesia

Front 64

What part of the cerebellum also plays a role in orientation of your body for ex. Pointing and moving and when you have a problem with this what is it called?

Back 64

Neocerebellum and it is called Dysmetria

Front 65

A right cerebellar lesion might cause you to tremor in your hand as you move it from one point to another and this tremor tends to be perpendicular what is this called?

Back 65

An intention tremor and a it is called a terminal tremor at the end of the movement

Front 66

A person with a neocerebellar lesion can be either side of the body and someone who tends to say each syllable equally stressed then that person would be said to have?

Back 66

scanning speech or telegraphic speech and speech patterns get lost as well

Front 67

A lesion here might cause someone to have their feet should width apart with a broad based stance and doing your best John Wayne impression so where is the lesion?

Back 67

Spinocerebellum

Front 68

If you turn and you’re turning to the side without the lesion you tend to swing your leg out wider around the turn so where is the lesion?

Back 68

spinocerebellum

Front 69

If you test your myotatic reflex on the patella you have a slower response and you also get a pendulum-like movement afterwards so where is the lesion?

Back 69

spinocerebellum on the same side as the lesion

Front 70

The output from the neocerebellum projects to?

Back 70

dentate nucleus (ipsi)

Front 71

Spinocerebellum projects to what nuclei?

Back 71

interposidus nuclei (emboliform and Globosus)

Front 72

The flocula nodulus/vermis projects to what nuclei?

Back 72

fastigial nucleus fastigial sends its output to the CNVIII and also the Thalamus

Front 73

The flocula nodulus and CN VIII have a 1 to 1 relationship so how do you know which one has the lesion? A person who stands on one leg with his eyes closed falls over and right beforehand feels dizzy this person has?

Back 73

a CN VIII lesion.

Front 74

A person stands on one leg with their eyes closed and falls over is said to have a lesion where?

Back 74

In his flocula nodulus/vermis (not dizzy) or Vestibulo cochlear nerve (dizzy.) It’s 1 to 1.

Front 75

Vestibulo spinal tract helps with?

Back 75

balance in your legs or posture muscles

Front 76

Alpha motor neurons stimulate Renshaw Cells and renshaw cells ______________ alpha motor neurons.

Back 76

inhibit

Front 77

The direct effect of gamma motor neurons is to?

Back 77

innervate the striated muscle portion of the muscle spindles.

Front 78

Golgi tendon organs provide?

Back 78

negative feedback control of muscle tension.

Front 79

Fisciculation of a muscle may be a sign of?

Back 79

a very recent LMN lesion in the path controlling that muscle

Front 80

A positive Babinski sign would indicate the presence of?

Back 80

an old UMN lesion in the path controlling that foot.

Front 81

Six months after a stroke destroyed neurons of hand area of the left primary motor cortex her right hand will show?

Back 81

a strong grasp reflex when the palm is touched

Front 82

A person with a sever spontaneous movement disorder that is ballism has been treated with surgical interruption of the pathway between globus pallidus to the thalamus and after surgery he will likely show?

Back 82

negative symptons such as mask-like face

Front 83

A lesion of the right side of the spinocerebellum will result in?

Back 83

a broad-based stance

Front 84

The fastigial nucleus sends out output directly to?

Back 84

the nucleus of CNVIII

Front 85

A person has difficulty with patterns in his left hand. This lesion is where?

Back 85

Left neocerebellar cortex

Front 86

LMN lesion affecting the innervation of the leg and foot will produce a short period of temporary?

Back 86

fasciculation

Front 87

A lesion in the leg area of the left primary motor cortex will cause what temporary symptom in the right leg?

Back 87

flaccid paralysis

Front 88

A positive babinski sign in the right foot could result from?

Back 88

A lesion of the left primary motor cortex a month ago

Front 89

A year after a person has a stroke that damaged the foot area of his right motor cortex he would show what?

Back 89

hyperreflexia of his left leg

Front 90

In the clasp knife reflex the resistance to passive bending of a joint changes abruptly as?

Back 90

inhibition by golgi tendon organ afferents exceeds excitation by spindle afferents

Front 91

A LMN injury will lead to permanent?

Back 91

flaccid paralysis

Front 92

an UMN lesion will lead to a relatively short period of?

Back 92

flaccid paralysis

Front 93

An early temporary symptom of a lower motor neuron lesion is?

Back 93

fasciculation

Front 94

An early temporary symptom of UMN lesion is?

Back 94

flaccid paralysis

Front 95

When a patients right patellar tendon is struck with a rubber hammer, his knee jerk reflex is slower than normal, and his leg continues swinging for a while afterward. He most likely has a lesion in his?

Back 95

Right spinocerebellum

Front 96

The golgi tendon organ provides?

Back 96

negative feedback regulation of muscle tension

Front 97

Type Ia (Dynamic) afferent fibers carry information about?

Back 97

the rate at which muscle length is changing

Front 98

Flaccid paralyis may result from?

Back 98

1. A recent UMN lesion
2. An old (more than a week) LMN lesion

Front 99

An old more than a week UMN lesion results in?

Back 99

Flaccid paralysis

Front 100

A positive Babinski sign may result from?

Back 100

An old more than a week UMN lesion

Front 101

Scanning speech is a sign of?

Back 101

a lesion in the neocerebellum

Front 102

A broad based stance and gait might result from?

Back 102

a lesion of the spinocerebellum

Front 103

A person trying to stand on one foot with his eyes closed falls over but does not feel dizzy, he most likely has a lesion in his?

Back 103

Fastigial nucleus

Front 104

Output from the basal nuclei is primarily from the?

Back 104

globus pallidus and goes to the thalamus

Front 105

Intention tremor is a sign of?

Back 105

a lesion in the neocerebellum

Front 106

Information from the neocerebellar cortex leaves the cerebellum along the axons that originate in?

Back 106

dentate nucleus

Front 107

Most of the output from the basal nuclei is from the?

Back 107

globus pallidus to the thalamus

Front 108

A person has trouble moving his right hand back and forth in pattern. He likely has a lesion where?

Back 108

His right neocerebellum

Front 109

In the renshaw cell reflex, the renshaw cell is?

Back 109

stimulated by alpha motor neuron and inhibits alpha motor neuron

Front 110

Afferent neurons from muscle spindles excite?

Back 110

alpha motor neurons

Front 111

1a Dynamic afferent neuron carries information about?

Back 111

the rate of change in length of a skeletal muscle