basal ganglia

Question 1

the basal ganglia sometime referred to as the extrapyramidal system, include the following structures _______

Answer 1

the substantia nigra (SN)
striatum (caudate and putamen)
globus pallidus (GP)
subthalamic nucleus (STN) and thalamus

Question 2

the _____ consists of the caudate nucleus and putamen

Answer 2

striatum

Question 3

the _____ consists of the globos pallidus and putamen

Answer 3

lentiform nucleus

Question 4

the ______ consists of lentiform nucleus and caudate nucleus

Answer 4

corpus striatum

Question 5

the ________ lies between the lentiform nucleus and the insular cortex. It has reciprocal connections between the sensory cortices (visual cortex)

Answer 5

claustrum

Question 6

Modulate the initiation, termination, amplitude and selection of movement (initation and selection)

Answer 6

the function of basal ganglia

Question 7

learning –> response outcome associations, stimulus response association

Answer 7

second function of the basal ganglia

Question 8

input nuclei of the basal ganglia

Answer 8

caudate and putamen (together with striatum)

Question 9

intrinsic nuclei of the basal ganglia

Answer 9

subthalamic nucleus (STN)

External segment of globus pallidus (GPe)

Question 10

output nuclei of the basal ganglia

Answer 10

substantia nigra pars reticulata (SNr)

internal segment of globys pallidus (GPi)

Question 11

neuromodulator of basal ganglia

Answer 11

substancia nigra pars compacta (SNc)

Question 12

what are the dvisions of the basal ganglia

Answer 12

corpus striatum, caudate nucleus, lentiform nucleus neostriatum or striatum, (putamen, globus pallidus external segment)

nucleus accumbens, subthalamic nucleus, substantia nigra (pars compacta, pars reticulata)

Question 13

what basal ganglia structures have common embryological origin, identical histological appearances, and similar connections

Answer 13

putamen, caudate nucleus, nucleus accumbens

Question 14

what 3 structures make up the striatum

Answer 14

putamen, caudate, accumbens

Question 15

what 2 structures make up the lenticular or lentiform nucleus

Answer 15

putamen and globus pallidus

Question 16

_____ and _____ are the major forebrain components of the basal ganglia

Answer 16

the striatum and globus pallidus

Question 17

the _____ and the _____ form by far the largest part of the basal ganglia , yet they have no way to affect motor neurons directly

Answer 17

striatum and globes

Question 18

______ recieves inputs from motor and somatosensory areas of cortex and projects by way of the globes pallidus and thalamus to the motor, premotor, and supplementary motor areas

Answer 18

putamen

Question 19

the ________ is involved more prominently in cognitive functions and less directly in movement (because of its limbic connections)

Answer 19

the caudate

Question 20

what is the direct pathway from the cortex to the thalamus

Answer 20

CORTEX —glutamate (+)—> PUTAMEN —gaba(-)—> INNER GP –gaba (-)—> VA/VL THALAMUS

THALAMUS —-glutamate(+) –> CORTEX

Question 21

what is the indirect pathway from the cortex to the thalamus

Answer 21

CORTEX –(glutamate (+)) –> PUTAMEN –(gaba (-))–> EXTERNAL GP–(gaba (-))–> STN –(glutamate (+))–> INNER GP –(gaba (-))–> Va/ VL THALAMUS

Question 22

hipokinetic disorders cause a dopamine ___________ activity in the direct pathway

Answer 22

increase activity

Question 23

hipokinetic disorders cause a ______ activity, indirect = _____ direct = ____ in thalamic inhibitions

Answer 23

decrease indirect
increase direct
increase in thalamic inhibition

Question 24

hyperkinetic disorder

eGP projections early degeneration in HF= if there is no ihibition = ______ activity indirect pathway

Answer 24

increase

Question 25

symptoms of movement disorders

Answer 25

rhythm, velocity, duration, pattern (repetitive, continuous, paroxismal, dirunal) exacerbation, action or with exercise voluntary suppression or sensory tricks anxiety

Question 26

pyramidal or extrapyramidal? babinski muscle hypertonia: spasticity cremasteric reflex absent

Answer 26

pyramidal

Question 27

pyramidal or extrapyramidal? loss of movement superficial abdominal reflexes absent

Answer 27

pyramidal

Question 28

pyramidal or extrapyramidal? severe paralysis (little or no atrophy) muscle hypertonia: rigidity

Answer 28

extrapyramidal

Question 29

pyramidal or extrapyramidal? profound reflexes exaggerated chorea, atetosis, dystonia, ballism etc

Answer 29

extrapyramidal

Question 30

the conection between the STN and GPi and between STN and GPe is excitatory

Answer 30

neurological basis of dysfunction in PD i think normally STN---> GPi= excitatory STN--> Gpe= inhibitory

Question 31

what receptors in the dorsal (motor) striatum and are the most relevant to the pathophysiology of parkinsons?

Answer 31

D1 and D2 because they are activated by the dopaminergic pathway from the SNc and terminating in the striatum

Question 32

what receptors are more abundant in the mesolimbic or emotional part of the brain? which receptors for hippocampus and hypothalamus?

Answer 32

D3 and D4= mesolimbic emotional D5= hippocampus/ hypothalamus

Question 33

Dopamine deficiency in the ________ pathway such as seen in parkinsons, cause denervation hypersensitivity of _________ receptors

Answer 33

nigrostriatal pathway D1 and D2 receptors

Question 34

In PD a reduction of dopamine from 550k to 100k leads to dopamine depleteion in the SN and in the nigrostriatal pathway to the caudate and putamen. this in turn results in an ______ of the indirect pathway, functionally ___________ the Subthalamic nucleus

Answer 34

a overactivity of the indirect pathway, functinally disinhibting the STN (subthalamic nucleus)

Question 35

in PD decreased inhibtion of the direct pathway causes additional disinhibtion of the ________.

Answer 35

output nuclei (GPi and SNr)

Question 36

in PD increased output put from GPi causes ________________ of the thalamus and reduced excitatory input to the motor cortex, which ultimately expressed as _________.

Answer 36

increased inhibition of the thalamus bradykinesia (slowing)

Question 37

what activity prevalent in the basal ganglia thalamocortical circuit, may be important in mediating certain parkinson features such as bradykinesia and tremor, and can be reducdd by dopaminergic treatments

Answer 37

synchronized oscillaroy activity in the 10-50 hz band (often termed the beta band)

Question 38

surgical treatments of PD, such as lesion placement within or stimulation of GPi or STN, may act by?

Answer 38

desynchronizing the oscillatory basal ganglia-thalamo-cortical network activity

Question 39

what are adaptive mechanisms in PD due to dopamine depletion?

Answer 39

increase in the synthesis of dopamine in surviving neurons and increasing the afferents to the dendrites of dopamenergic neurons Proliferation of D2 receptors, as well as co-localization of D1 and D2 receptors gap junctions, increase dramatically after dopaminergic denervation

Question 40

________, ________,and _____ particularly in the substantia nigra pars compacta and in the pontine locus ceruleus, are typical abnormalitis found in the brains of patients with PD

Answer 40

depigmentation, neural loss and gliosis

Question 41

round, eosinohilic, intracytoplasmic neuronal inclusions

Answer 41

lewy bodies

Question 42

size of lewis bodies

Answer 42

3-25 nm in diameter with dense granular core 1-8 nm

Question 43

loosley arranged fibrillary elements extending towards a peripheral halo

Answer 43

lewy bodies

Question 44

immunohistochemical studies have demonstrated that lewy bodies are made up of mainly

Answer 44

alpha-synuclein and ubiquitin other things

Question 45

a 140 amino acid presynaptic protein found mutated in rare families with PD, it stains

Answer 45

alpha-synuclein in lewis bodies

Question 46

percentage comparison of neurons in substantia nigra undergoing apoptosis in ppl with PD and normal

Answer 46

normal = .5% fourfold PD= 2%

Question 47

intracellular inclusions that are pathologic hallmark of PD

Answer 47

lewy bodies

Question 48

braak staging- in the traditional view, the pathologic process of PD starts with degeneration of ____________ in the _______

Answer 48

dopaminergic neurons in the substantia nigra

Question 49

heiko braak propsed that the pathologic changes of PD start in the _______________ and in the _________ progressing rostrally over many years to the ________ in a predictable six stage process.

Answer 49

medulla of the brainstem and in the olfactory bulb cerebral cortex

Question 50

what clinical features are noticed in the gait of a patient with PD? what happens in the later stages ?

Answer 50

stooping, slow initiate walking, shortened stride, rapid small steps, tendency to run, reduced arm swing, impaired balance on turning falls common in later stages

Question 51

what clinical features are noticed in the speech of a patient with PD? what happens in the later stages ?

Answer 51

monotone--> tremulous, slurring dysarthria | soft, rapid, indistinct

Question 52

what clinical features are noticed in cognition of a patient with PD? what happens in the later stages ?

Answer 52

impaired in 1/3 of patients (loss of executive functions including planning, decision making, controlling emotions) depression

Question 53

what clinical features are noticed in the gi and other of a patient with PD? what happens in the later stages ?

Answer 53

constipation, heartburn, dribbling, dysphagia, weightloss greasy skin microphagia

Question 54

inhereted autosomal dominant movement disorder that is traced to a single gene defect on chromosome 4

Answer 54

huntington disase

Question 55

huntington disase is associated with a degeneration of the cholinergic and _______________ of the _______. it is accompanied by ________ atrophy in the frontal and temporal lobes.

Answer 55

GABA- ergic neurons of the striatum gyral atrophy

Question 56

clinical signs include choreiform movements, hypotonia, and progressive dementia

Answer 56

huntington disase

Question 57

is the most common cause of chorea overall. It occurs primarily in girls, typically after Rheumatic fever

Answer 57

sydenham chorea (St. Vitus dance)

Question 58

usually occurs during the second trimester of pregnancy. Many patients have a history of sydenham chorea

Answer 58

chorea gravidarum

Question 59

usually results from a vascular lesion of the subthalamic nucleus. Clinical signs include violent contralateral flinging (ballistic) movements of one or both extremities. Subthalamic nuceli luys

Answer 59

Hemiballism

Question 60

wilsons disase

Answer 60

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