Neuro Things U Should Know By Now (Test2, Week1)

Front 1

Halmark - deficits limited to distribution of nerve.

Back 1

Peripheral compartment lesion.

Front 2

Hallmark - no involvement of the face.

Back 2

Spinal compartment lesion

Front 3

Hallmark - crossed signs - deficits of the head are contralateral to deficits of the body.

Back 3

Posterior fossa lesion

Front 4

Accompanying damage to the cranial nerve nucleus, or root, results in cranial nerve deficits ___________ to the lesion, because peripheral nerves do not cross the midline.

Back 4

Ipsilateral

Front 5

Lesions of the _____________ may be accompanied by altered states of consciousness, since the reticular activating system, responsible for maintaining consciousness, is located throughout the ___________ ___________.

Back 5

Brainstem
Brainstem tegmentum

Front 6

Hallmark - all sensor and motor deficits (body and head) are on the same side.

Back 6

Supratentorial lesion

Front 7

Location of:
LMN
UMN

Back 7

Spinal cord or brainstem

Brainstem or cerebral cortex

Front 8

What cranial nerves are in the supratentorial fossa? Where are the rest?

Back 8

CN I, II

CN roots are in the posterior fossa.

Front 9

Where in the anterior horn are the flexors and extensors, relative to one another?

Back 9

Flexors - Posterior
Extensors - Anterior

Front 10

Where in the anterior horn are the innervators of paravertebral/proximal and the distal musculature, relative to one another?

Back 10

paravertebral/proximal - medial

distal musculature - lateral

Front 11

The _______________ coordinates activity in the UMN arising from both the brainstem and the cortex.

Back 11

Cerebellum (think Timing)

Front 12

Motoneurons that innervate skeletal muscles:

Back 12

LMN

Front 13

Thoracic level innervates only axial musculature, so the anterior horn at thoracic levels is narrow and only contains ______________ _____________

Back 13

Proximal motoneurons

Front 14

*** What is located in the Lateral White Columns of the spinal cord (page 21-3, cervical level)***

Biased toward innervation of the _______ __________ muscles

Back 14

Lateral CSpT
RST
Lat (med) RetSp

distal flexor

Front 15

***Located in the ventral and medial white columns of the spinal cord.***

Involved in muscle tone and posture.

Back 15

Med (pontine) RetSp
Lat VestSp
TecSp
Ant CSpT

Front 16

________ _________ exists between the primary motor cortex and alpha motor neurons, with no intervening synapses.

Back 16

Direct pathway

Front 17

How does information form the cerebral cortex reach lower motor neuron pools directly?

Back 17

Corticospinal Tract

Front 18

The following are signs of Upper or Lower Motor Neuron Lesions?
weakness (paresis, paralysis-flaccid)
hypotonia
areflexia
atrophy
fasciculations

Back 18

Lower Motor Neuron Lesions

Front 19

The following are signs of Upper or Lower Motor Neuron Lesions?
weakness (paralysis)
spasticity (hypertonia)
hyperreflexia
clonus
Babinski sign
disuse atropy

Back 19

Upper Motor Neuron Lesions

Front 20

Decortication removes the cerebral cortical influence over brainstem motor nuclei. What tract causes the tonic contraction of the arms (1), and tonic extension of the legs (2)

Back 20

RST

RetSp, and VestSp

Front 21

Decerebration occurs after midbrain damage severe enough to render the _____ __________ nonfx. This results in tonic extension of extremities.

Back 21

red nucleus

Front 22

In general, corticobulbar projections to most cranial nerves are ___________. The corticobulbar projections to cranial nerve VII are unique in that they are ___________.

Back 22

Bilateral
Asymmetrical

Front 23

CN VII
Lower face
Upper face

Back 23

contral lower (below eye)
Ipsilateral and contra upper

Front 24

Lower part of the face receives corticobulbar innervation only from the _____________ side.

Back 24

contralateral

Front 25

Does the upper part of the face receive input from contralateral or ipsilateral corticobulbar tract?

Back 25

BOTH

Front 26

Why might a lesion that damages the abducens nucleus may also damage fibers leaving the facial nerve, finding an internal strabismus of the ipsilateral eye.

Back 26

because as axons leave the facial nucleus, they wrap aroud the abducens nucleus.

Front 27

The following are typical Upper or Lower Montoneuron Signs?
Paresis
Signs of muscle denervaton
Flaccidity
Decreased or absent stretch reflex

Back 27

Lower

Front 28

Higher of Lower Level of Hierarchical Organization of Cortex/Brainstem/Sp Cord?
_________ Levels direct voluntary movements
________ Levels coordinate muscle activity in a wide variety of movements.

Back 28

Higher

Lower

Front 29

Are there direct motor projections into spinal cord from basal ganglia and or cerebellum?

Back 29

No

Front 30

Explain the size principle?

Back 30

Motor units are typically recruited by smaller force, and smaller fatigability before larger force and larger fatigability.

This enables smooth force production and efficient energy utilization.

Front 31

When individual twitches summate this produces max force which is called

Back 31

Tetanic force

Front 32

Control over alpha mn recruitment and firing rate modulation is achieved by regulating the a) _________ ________ and b) _____ ______________.

Back 32

Synaptic input

alpha-mn excitability

Front 33

Can the spinal cord itself alter muscle coordination based on sensory feedback in the absence of any descending information?

Back 33

Yes

Front 34

Can spinal circuts change dramatically as a result of training or in response to injury or disease?

Back 34

Yes

Front 35

__________ Unit assists in opposing stretch and restoring the intended position of the displaced limb.

Back 35

Myotatic

Front 36

M-wave or H-wave?
Has the shorter time delay from stimulation.

Back 36

M-wave (Results from direct activation of motor units)

H wave takes longer because it is from activation of the stretch reflex circuit.

Front 37

Hyperactive stretch reflexes, increased resistance to rapid muscle stretch.

Back 37

Spasticity

Front 38

Uncontrolled oscillating limb movement initiated by muscle stretch.

Back 38

Clonus

Front 39

Stretch reflexes evoked by a quick stretch.

Back 39

Deep Tendon Reflexes
or
Tendon Jerks

Front 40

Stretch reflexes produced by slow or maintained stretch.
Contribute to muscle tone

Back 40

Tonic Stretch Reflexes

Front 41

Which provides the first neural protection against falling.
1 Stretch reflex
2 Vestibular response
3 Visual response

Back 41

Stretch Reflex

Vestibular and visual have longer delays

Front 42

Cortical motor signs
__________ presents as weakness which may be present with spasticity, increased resistance to passive movement, and can dramatically alter gait.

Back 42

Hemiparesis

Front 43

_________ _____________ the leg is swung in a semicircle from the hip with the pelvis tilted upward and hip abducted. The knee may be hyperextended due to innappropriate quad activity. Arm may be held flexed and adducted with minimal swing.

Back 43

Spastic Hemiparesis

Front 44

Why aren't umn technically motoneurons?

Back 44

They do not directly connect with muscles, but they do convey motor commands to the lmn.

Front 45

Upper motoneuron Signs
Hemiparesis of large muscle groups ____________ to the site of cortical injury.

Back 45

Contralateral

Front 46

________ _________ refers to the changes that occur in the organization of the brain as a result of experience.

Back 46

Cortical plasticity

Can occur with in weeks after infarct.

Front 47

Theory
Precision in direction, force etc, is encoded not by single neurons but by a ______________ of neurons.

Back 47

Population

ie by a population code.

Front 48

Neurons in the Supplementary motor area and Lateral premotor cortex area are activated during prep for movement by (5)

Back 48

Sequencing movements
Associating sensory cues with motor response
Delaying task execution
Conforming hand shape to objects
Using visual imagery to plan movement

Front 49

Following lesions to the _______ _________ ______, subjects cannot associate movements with visual cues, ie subjects cannot make visuomotor associations.

Back 49

Dorsal premotor area

Front 50

Primary motor cortex (M1)
More active in response to visual or memory cues, or equally responsive to both?

Back 50

Equally responsive to both

Front 51

Lat Premotor Cortex (PM)
More active in response to visual or memory cues, or equally responsive to both?

Back 51

More active in response to visual cues

Front 52

Supplementary Motor Area (SMA)
More active in response to visual or memory cues, or equally responsive to both?

Back 52

More active in response to memory.

Front 53

This hallmark of cerebellar disorders is a difficulty with coordinating movement, manifested by inaccuracies of limb placement (dysmetria) and by defects in timing of muscle activity.

Back 53

Ataxia

Front 54

A tremor is regular in frequency and wavelength.
How is an "action tremor" different?

Back 54

It is increasing and erratic

Front 55

____________ _______ characterized by sliding and stretching of words, and slurring of phonation, which is associated with cerebellar defects, often accompanied by inappropriate rate, range, force, and direction of voluntary movements

Back 55

Scanning speech

Front 56

Hyperkinetic Basal Ganglia Disorders (4)

Back 56

Chorea
Athetosis
Ballism
Dystonia

Front 57

Hypokinetic Basal Ganglia Disorders (4)

Back 57

Akinesia
Bradykinesia
Rigidity
Resting Tremor

Front 58

Subthalamic nucleus determines pattern of firing, true or false?

Back 58

TRUE

Front 59

Basal Ganglia
Input nuclei (2)

Back 59

Caudate nucleus
putamen?

Front 60

Basal Ganglia
Output nuclei (2)

Back 60

Globus pallidus
Substantia nigra, pars reticulata

Front 61

Basal Ganglia
Output projecting to VL and VA thalamic nuclei are GABAergic (inhibitory) or glutaminergic (excitatory)?

Back 61

GABAergic (inhibitory)

Front 62

Basal Ganglia
Output: VL and VA thalamic nuclei projecting to the cortex is GABAergic (inhibitory) or glutaminergic (excitatory)?

Back 62

glutaminergic (excitatory)

Front 63

Basal Ganglia extra fact:

Back 63

Through the VL VA projections the basal ganglia influences descending motor pathways such as CSpT and corticobulbar systems. The SNr also projects to the superior colliculus where it tonically inhibits saccadic eye movement.

Front 64

Damage to "higher centers" (association cortex, basal ganglia, and cerebellum) can cause distinctive movement abnormalities (involuntary movements, incoordination, difficulty initiating movement) but is not accompanied by substantial ______________

Back 64

Weakness

Front 65

Damage to upper or lower motor neurons causes weakness and a distinctive set of accompanying symptoms and signs?

Back 65

Both upper and lower

Front 66

What are Betz cells?

Back 66

pyramidal cell neurons located within the fifth layer of the grey matter in the primary motor cortex. These neurons are some of the largest in the central nervous system, sometimes reaching 100 μm in diameter. Betz cells send their axons down to the spinal cord where in humans they synapse directly with anterior horn cells, which in turn synapse directly with their target muscles.

Front 67

What three areas give input to the Corticospinal Tract?

Back 67

Primary motor cortex
Premotor cortex
Supplementary Motor Area

Front 68

Premotor or Supplementary Motor Area
Important for movements guided by external stimuli.

Back 68

Premotor

Front 69

Premotor or Supplementary Motor Area
Important in planning and learning complex, internally generated movements.

Back 69

Supplementary Motor Area

Front 70

What happened when monkey's medullary pyramids were cut?

Back 70

Not much, except they could no longer pinch.

Front 71

Which two tracts can compensate for the role normally played by the CSpT in most aspects of voluntary movement?

Back 71

Rubriospinal & RetSp

Front 72

Often attributed to inhibition of motor neurons by reflex connections of Golgi tendon organs.

Back 72

Clasp-knife effect

Front 73

Hyperreflexia + Hypertonia =

Back 73

Spasticity

Front 74

Upper or Lower MN damage
Clonus
Spasticity
Distal muscles recover less

Back 74

Upper

Front 75

Where do Corticospinal fibers end? (4)

Back 75

Spinal motor neurons
Posterior Horn
Intermediate gray matter
Interneurons of anterior horn

Front 76

Motor neurons to the lower facial muscles are innervated mainly by contralateral cortex. Those to the upper facial muscles are innervated ____________.

Back 76

Bilaterally

Therefore, if U have unilateral corticobulbar damage, U can't smile or puff out cheeks on contralateral side, but you can raise your eyebrows.

Front 77

____________ tract is commonly used to refer selectively to those fibers that affect the motor neurons of cranial nerves.

Back 77

Corticobulbar tract is commonly used to refer selectively to those fibers that affect the motor neurons of cranial nerves.

Front 78

In general Cranial Nerve nuclei receive ___________ corticobulbar innervation.

Back 78

bilateral

Front 79

Most corticobulbar fibers act through interneurons of the __________ formation.

Back 79

Reticular

Front 80

What three CN do not receive corticobulbar fibers?

Back 80

CN 3, 4, 6
Occulomotor, Trochlear, Abducens

Front 81

What is the blood supply to the basal ganglia?

Back 81

Perforating branches of the circle of willis, more specifically, the lenticulostriates.

Front 82

The following three structures make up the _________.
Caudate N
Nucleus accumbens
Putamen

Back 82

Striatum

Front 83

The Lenticular nucleus is made up of (2)?

Back 83

Putamen
Globus pallidus

Front 84

The globus pallidus has two segments, what are they?

Back 84

external (GPe)
internal (GPi) (inhibitory)

Front 85

What are the four parts of the Basal Ganglia?

Back 85

Striatum
Globus pallidus
Subthalamic N
Substantia nigra

Front 86

What two parts make up the Substantia nigra?

Back 86

Compact part (SNc)
reticular part (SNr) (inhibitory / GABAergic)

Front 87

A small lens-shaped nucleus in the brain where it is a part of the basal ganglia system. Located ventral to the thalamus. It is also dorsal to the substantia nigra and medial to the internal capsule.

Back 87

Subthalamic Nucleus

Front 88

Substantia nigra two parts
a) Contains closely packed, pigmented neurons.
b) Nearer the cerebral peduncle that contains more loosely packed neurons, most of which are unpigmented.

Back 88

a) compact part (SNc)
b) reticular part (SNr)

Front 89

Substantia nigra two parts
a)provides widespread, modulatory, dopaminergic projections to other parts of the basal ganglia
b) Is one of the basal ganglia output nuclei

Back 89

a) compact part (SNc)
b) reticular part (SNr)

Front 90

Generally involved in most cortical functions.
Loops form the basis of this involvement, starting from an area of cerebral cortex to _______ _______ and then returning, by way of the thalamus, to part of this cortical area.

Back 90

Basal Ganglia

(movement, cognition, emotion, motivation)

Front 91

The corticostriate inputs and the projections back to the cortex from the thalamus all make excitatory connections. What is the neurotransmitter involved?

Back 91

Glutamate

Front 92

The GPi SNr outputs are all inhibitory. What neurotransmitter is involved?

Back 92

gamma aminobutyric acid (GABA)

Front 93

What is the only way the basal gangial can influence movement?

Back 93

By affecting he activity of of motor areas of the cerebral cortex, and the reticular formation.

Front 94

Somatosensory and motor ---> striatum (mainly putamen) ----> GPi ----> Ventral ant and Ventral Lat nuclei (VA/VL) ---> motor areas of cortex

Back 94

Basal ganglia circuitry that modulate cortical output

Front 95

The caudate n, putamen and ventral striatum receive input from (4)

Back 95

Cerebral cortex *
SNc
Ventral tegmental area
Intralaminar nuclei of the thalamus

Front 96

The ________ nucleus, as it curves around the ventricular system, receives most of the projections form association areas.

Back 96

caudate

Front 97

The ventral _________ receives inputs from the limbic cortex, the hippocampus and the amygdala.

Back 97

striatum

Front 98

Destruction of the nigrostriatal pathway is the major factor causing ____________ ___________.

Back 98

Parkinson's Disease.

Front 99

The __________ is probably centrally involved in most of the motor fx of the basal ganglia.

Back 99

putamen

Front 100

The ________ nucleus is involved more prominently in cognitive fx, and less directly involved in movement.

Back 100

caudate

Front 101

Which part of the globus pallidus receives inhibitory inputs from the striatum and excitatory inputs from the subthalamic nucleus?

Back 101

Both! GPe and GPi

So, input is basically the same*, output is different.
Diagram page 485 Nolte
* GPi also receives input from GPe

Front 102

Globus Pallidus external OUTPUT

Back 102

Inhibitory GABA to most other parts of the basal ganglia.

Front 103

Globus Pallidus internal OUTPUT

Back 103

Projects mainly to the thalamus (pg 484)

Front 104

The subthalamic fasciculus is a bundle of fibers that interconnects the ________ ______ and the______ ________.

Back 104

Subthalamic N and Globus Pallidus

These cortical inputs provide the most rapid access to basal ganglia output nuclei (cortex->sub n->GPi) and are thought to play a central role in the basal ganglia fx.

Front 105

SNr receives input from the striatum, GPe, and subthalamic nucleus and projects to the VA/VL and the dorsomedial nucleus of the thalamus...just like the ______

Back 105

GPi
But SNr is more important route for info from the caudate nucleus than the GPi

Front 106

There are also projections from the SNr to the superior colliculus and the reticualr formation. The cx w/ the sup colliculus is one route thru which the basal ganglia participate in ____ movement.

Back 106

eye

Front 107

Name the arterial branch that supplies the following:
SNr & Sub N:
Striatum:
Globus pallidus:

Back 107

SNr & Sub N: PCA
Striatum: Lenticulostriate
Globus pallidus: Ant Choroidal Art

Front 108

Patients body is bent or twisted into an abnormal, relatively fixed posture.

Back 108

Dystonia

Front 109

Slow writhing movements most pronounced in the hands and fingers, so that pt may not be able to keep affected limb in a fixed position.

Back 109

Athetosis

Front 110

In case of athetosis, where is most likely location of lesion?

Back 110

Striatum

Front 111

In case of hemiballismus, where is most likely location of lesion?

Back 111

contralateral basal ganglia

Front 112

An invasive procedure, primarily effective for tremors such as those associated with Parkinson's Disease (PD), where a selected portion of the thalamus is surgically destroyed (ablated). Neurosurgeons use specialized equipment to precisely locate an area of the thalamus, usually choosing to work on only one side (the side opposite that of the worst tremors).

Back 112

Thalamotomy

Front 113

Too much L-DOPA can cause

Back 113

Choreform and Athetosis

Front 114

Changes in the pattern of firing in various parts of the basal ganglia are responsible for the symptoms in 2 disorders.

Back 114

Huntington's
Parkinson's

Front 115

GPi to thalamus is inhibitory, thalamocortical projections are excitatory. So, if you decrease GPi fx, you will _________ the excitatory effect the thalamus has on the cortex.

Back 115

increase

cortex --> striatum --> GPi-SNr --> thalamus --> cortex

Front 116

Movements of hemiballismus result from direct damage to the contralateral ___________ nucelus

Back 116

subthalamic

which would decrease the firing rate of GPi-SNr neurons, causing the thalamus to have a larger excitatory effect on the cortex. (page 489)

Front 117

Cerebral cortex projects to the cerebellum via the ________ nucleus.

Back 117

Pontine

Front 118

_________ damage results in abnormalities of equilibrium, postural control, and coordination of voluntary movements.

Back 118

Cerebellar

Front 119

What part of the cerebellum is very close to the foramen magnum and is often involved in herniation and compression of the medulla?

Back 119

cerebellar tonsil

Front 120

Which part of the cerebellar peduncle is composed mainly of afferents from the spinal cord and brainstem to the cerebellum?

Back 120

Inferior cerebellar peduncle.

Front 121

Which part of the cerebellar peduncle is exclusively of afferents from the pontine nuclei of the contralateral side to the cerebellum?

Back 121

Middle cerebellar peduncle

Front 122

Which part of the cerebellar peduncle contains the major efferent pathways from the cerebellum to the red nucleus and thalamus?

Back 122

Superior Cerebellar Peduncle.

Front 123

Consequences of cerebellar damage are much more severe and long lasting when the _____ _______ are included in the lesion.

Back 123

Deep nuclei

Front 124

Fractured somatoatopy is used to describe the pattern in the cerebellar cortex. What does that mean?

Back 124

‘fractured somatotopy’ suggests that precise topographical relations between adjacent receptive fields do not appear to be preserved

Front 125

The vermis and medial hemispheres preferentially receive their cortical input from the ________ ________ of the precentral gyrus.

Back 125

Motor cortex

Front 126

The lateral parts of the cerebellar hemispheres receive most of their cortical input from _________, _____________, and association areas of the cerebral cortex

Back 126

premotor and somatosensory

Front 127

Climbing fibers convey information, and arise in the ION. ION stands for:

Back 127

Inferior Olivary Nucleus

Front 128

The entire output of the cerebellar cortex is provided by axons of

Back 128

Purkinje cells

Front 129

All deep nuclei project back to the _______ cortex.

Back 129

Cerebellar

Front 130

Most neurons of the deep nuclei use __________ as a neurotransmitter and make excitatory synapses on neurons they contact.

Back 130

glutamate

Front 131

Projections from the deep nuclei to the inferior olivary nucleus arises from a separate population of inhibitory cells and uses ______ as their transmitter.

Back 131

GABA

Front 132

The human dentate nucleus project to two spots, what are they?

Back 132

Motor cortex
Prefrontal cortex

Front 133

Two tests that can be done to ascertain if there is damage to the cerebellum.

Back 133

PET, fMRI

Front 134

Is it typical to see lesions that only affect one side of the brain in the cortex and cerebellum?

Back 134

No, it is more typical that cerebellar defects are referable to the vermis, to one or both sides of the body of the cerebellum as a whole, or to the flocculonodular lobe.

Front 135

Damage due to lesions in the body of the cerebellum can result in neocerebellar syndrome.

Back 135

Characterized by variable combo of chgs in muscle tone, reflexes, and the coordination of voluntary movements, all ipsilateral to the side of the lesion.

Front 136

Most prominent clinical sign of cerebellar damage?

Back 136

Lack of coordination of voluntary movements.

Front 137

Damage to the medial hemisphere of the cerebellum can cause ataxia and _______ speech

Back 137

scanning

Front 138

Is neocerebellar syndrome accompanied by any sensory deficits?

Back 138

No

Front 139

Damage to the Flocculonodular lobe can cause
1)Loss of equilibrium
2) Problems with eye movements
Tumors in this area are called:

Back 139

Medulloblastomas, typical pt is young child, can cause non-communicating hydrocephalus.