BB EOYS1 Flashcards
Which supplies the medial portion of the globus pallidus?
anterior choroidal artery (AChA)
middle cerebral artery (MCA)
anterior cerebral artery (ACA).
posterior cererbral artrey (PCA)
lenticulostriate artery
Which supplies the medial portion of the globus pallidus?
anterior choroidal artery (AChA)
middle cerebral artery (MCA)
anterior cerebral artery (ACA).
posterior cererbral artrey (PCA)
lenticulostriate artery
Which supplies the anterior and inferior of the globus pallidus?
anterior choroidal artery (AChA)
middle cerebral artery (MCA)
anterior cerebral artery (ACA).
posterior cererbral artrey (PCA)
lenticulostriate artery
Which supplies the anterior and inferior of the globus pallidus?
anterior choroidal artery (AChA)
middle cerebral artery (MCA)
anterior cerebral artery (ACA).
posterior cererbral artrey (PCA)
lenticulostriate artery
Which supplies the superior and posterior of the globus pallidus?
anterior choroidal artery (AChA)
middle cerebral artery (MCA)
anterior cerebral artery (ACA).
posterior cererbral artrey (PCA)
lenticulostriate artery
Which supplies the superior and posterior of the globus pallidus?
anterior choroidal artery (AChA)
middle cerebral artery (MCA)
anterior cerebral artery (ACA).
posterior cererbral artrey (PCA)
lenticulostriate artery
A 65-year-old man was brought by his daughter to his provider due to tremors and increasing stiffness in both arms and legs. This has led the patient to fall twice while attempting to turn. On examination, the patient had increased muscle tone, resting tremors, and difficulty initiating movements when asked to move. A single-photon emission computed tomography (SPECT) was done, showing reduced uptake in the striatum. How would this reduced uptake affect the pathways?
A. It reduces inhibitory signals projected to the subthalamus.
B. It increases inhibitory signals projected to the subthalamus.
C. It reduces the stores of neurotransmitters present in the globus pallidus externus.
D. It increases inhibitory signals projected to the substantia nigra pars reticularis.
A 65-year-old man was brought by his daughter to his provider due to tremors and increasing stiffness in both arms and legs. This has led the patient to fall twice while attempting to turn. On examination, the patient had increased muscle tone, resting tremors, and difficulty initiating movements when asked to move. A single-photon emission computed tomography (SPECT) was done, showing reduced uptake in the striatum. How would this reduced uptake affect the pathways?
A. It reduces inhibitory signals projected to the subthalamus.
B. It increases inhibitory signals projected to the subthalamus.
C. It reduces the stores of neurotransmitters present in the globus pallidus externus.
D. It increases inhibitory signals projected to the substantia nigra pars reticularis.
Which of the following outputs to the superior colliculi?
globus pallidus external
globus pallidus internal
substantia nigra, pars reticula
subthalamic nuclei
Which of the following outputs to the superior colliculi?
globus pallidus external
globus pallidus internal
substantia nigra, pars reticula
subthalamic nuclei
What is the most common type of tremor in PD? [1]
pill-rolling’ rest tremor; looks like you are trying to roll a pill between your thumb and index
Basal ganglia input zones:
Where do the caudate nucleus and putamen have fibres inputing into / orginating from? [3]
- Cerebral cortex - specifically the frontal cortex: primary motor cortex and parietal cortex: primary somatosensory cortex
- substantia nigra pars compacta (from the midbrain)
- Local circuit neurons within the corpus striatum (GABAergic)
Describe the indirect pathway of the dorsal ganglia
Excitation of dorsal striatum causes the release of dorsal striatum GABA (inhibitory)
This causes projects onto globus pallidus external segment: causes increased inhibition of GPe
This causes the globus pallidus external segment to release inhibitory GABA onto the subthalamic nucleus: causes reduced inhibition of STN
This causes the subthalamic nucleus to release inhibitory GABA onto the globus pallidus internal segment: which increases the activation of GPi
This causes the globus pallidus internal segment to release inhibitory GABA onto the motor thalamus: which creates increased inhibition of motor thalamus
OVERALL DEACTIVATION OF MOTOR THALAMUS -> decreased motor cortex activation.
NO GO pathway.
Describe the effect of the activation of the D2 dopaminergic receptors
The D2 dopaminergic receptor activated:
- decreases cAMP
- Decreaes the sensitivity of striatal GABA neurons to glutamate (makes the glutatemate LESS EXCITABLE)
- Causes increased inhibition of the sub-thalamic nucleus
- This means get increaed inhibition of the GPi
- This causes less inhibition of the VL / VA
End result: INCREASED MOTOR ACTIVITY
Explain pathophysiology of Parkinsons disease [2]
-Loss of dopaminergic neurons in the substantia nigra, which project to and innervate the dorsal striatum.
- Less D1 and D2 activation
- The indirect pathway is therefore faciliated and becomes dominant
Name the 3 classic symptoms of Parkinsons disease [3]
bradykinesia, tremor and rigidity.
Name the symptoms of HD [4]
chorea - movement disorder that causes sudden, unintended, and uncontrollable jerky movements of the arms, legs, and facial muscles.
personality changes (e.g. irritability, apathy, depression) and intellectual impairment
dystonia
saccadic eye movements - abruptly change the point of fixation.
Describe what ballismus and Athetosis are [2] and what they’re caused by [2]
Athetosis:
* slow, involuntary regular writhing movements of the fingers, hands, toes and feet (in some cases, arms, legs, neck and tongue
* Lesions to the striatum; often a result of cerebral palsy
Ballismus:
* a type of chorea, usually involving violent, involuntary flinging of one arm and/or one leg (usually one side of the body is affected: Hemiballismus). The movements are wider and more intense than chorea
* Damage to subthalamic nucleus
What is the name for this symptom?
Lesions to which region causes this symptom?
Subthalamic nuclei
Substantia nigra
Pre supplementary motor area
Lentiform nucleus
Dorsal striatum
athetosis
Lesions to which region causes this symptom?
Subthalamic nuclei
Substantia nigra
Pre supplementary motor area
Lentiform nucleus
Dorsal striatum
What is the name for this symptom?
Lesions to which region causes this symptom?
Subthalamic nuclei
Substantia nigra
Pre supplementary motor area
Lentiform nucleus
Dorsal striatum
Ballismus
Subthalamic nuclei
Substantia nigra
Pre supplementary motor area
Lentiform nucleus
Dorsal striatum
Which mitochondrial metabolite is toxic to dopaminergic pathways? [1]
MPP+
The genetic link between familial PD is due to a link between which protein? [1] Which gene codes for this protein? [1]
Is PD genetic or environmental? [1]
genetic link with the protein alpha-synuclein coded by SNCA (duplications or triplications cause autosomal dominant familial PD)
disease emergence may be due to interactions environment x genes
Describe the link between mitochondrial toxicity and dopaminergic neurons [1]
What process is diruspted as a result of ^ [1]
The compound MPTP is a toxin which can be transformed into the metabolite MPP+ which is neurotoxic for dopaminergic neurons
Dysfunction of complex I of the mitochondrial respiratory chain
can lead to increased oxidative stress
Describe the mechanism of creation of dopamine [3]
L-tyrosine –> L-Dopa (Decarboxylated to create..) –> Dopamine
Dopamine binds to which two receptors? [2]
What are the subtypes of these receptors? [5]
D1-like Family Receptors:
* D1 & D5 subtypes
D2-like Family Receptors
* D2, D3 & D4 subtypes
Which drug used to treat Huntingdons Disease works by the mechanism of action depicted by A? [1]
Tetrabenazine
acts primarily as a reversible high-affinity inhibitor of mono-amine uptake into granular vesicles of presynaptic neurons by binding selectively to VMAT-2
Which treatment used in PD is good at managing tremors
Haloperidol
Ritotigone
L-DOPA
Orphenadrine
Which treatment used in PD is good at managing tremors
Haloperidol
Ritotigone
L-DOPA
Orphenadrine: anticholinergic
[] is defined as that part of the PFC in which saccades can be elicited
Superior colliculi
Inferior colliculi
Frontal eye fields
Supplementary eye field
[] is defined as that part of the PFC in which saccades can be elicited
Superior colliculi
Inferior colliculi
Frontal eye fields
Supplementary eye field
Damage to which of the following would cause someone to not be able to inhibit a response to a stimulus
A
B
C
Damage to which of the following would cause someone to not be able to inhibit a response to a stimulus
A: dorsolateral pre-frontal cortex
B
C
If you were sitting in a quiet room and all of a sudden heard a noise to your right, you would subconsciously turn your head in that direction and orient your eyes towards the direction of the sound, attempting to find the source. Which spinal tract would be responsible for this? [1]
Tectospinal tract
Which spinal tract provides drive to the respiration via the phrenic nerve?
Rubrospinal
Lateral vestibulospinal
Recticulospinal
Cortciospinal
Coticobulbar
Which spinal tract provides drive to the respiration via the phrenic nerve?
Recticulospinal
Pharmacological management of Parkinson’s disease
Name two drugs that can combined with L-DOPA (aka levodopa) that means it doesn’t get metabolised to dopamine outside the BBB [2]
What is their MOA? [1]
L-DOPA (levodopa) & carbidopa or benserazide
carbidopa, benserazide are decaboxylase inhibitors: allows L-DOPA to pass BBB where it can then be converted to dopamine
Pharmacological management of Parkinson’s disease
Name 3 dopminergic agonists and describe their MOA
Dopamine agonists:
* ropinirole
* pramipexole
* rotigotine (in BB PBL; transdermal patch)
Dopamine agonists act directly on the dopamine receptors and mimic dopamine’s effect
Which of the following dopamine agonists can be used as an infusion for major motor fluctuations?
bromocriptine,
pramipexole
ropinirole
rotigotine
Apomorphine
Which of the following dopamine agonists can be used as an infusion for major motor fluctuations?
bromocriptine,
pramipexole
ropinirole
rotigotine
Apomorphine
Pharmacological management of Parkinson’s disease
Name three drugs that are monoamine oxidase inhibitors [3]
Describe their MoA [1]
- rasagiline
- selegiline (in PBL)
- safinamide
MAO-B inhibitors stop Monoamine oxidase type B breaking down dopamine into DOPAC or homovanillic acid
What is the MoA of COMT inhibitors? [1]
Explain why [1]
Which drugs are they used in conjunction with? [1]
COMT is an enzyme involved in the breakdown of dopamine (DOPAC –> homovanillic acid) and hence may be used as an adjunct to levodopa therapy
Pharmacological management of Parkinson’s disease
Name 2 COMT inhibitors [2]
entacapone
tolcapone
Pharmacological management of Parkinson’s disease
What is the MoA of Amantadine? [3]
inhibits dopamine reuptake, increases dopamine release, also weak antagonist at NMDA glutamate receptors
Surgical approaches in Parkinson’s disease
Describe the surgical approaches to PD treatment [4]
Electrode stimulation of the subthalamic nucleus
Thalamotomy
Pallidotomy
deep brain stimulation for people with advanced Parkinson’s disease whose symptoms are not adequately controlled by optimised pharmacological therapy
Pharmacological management of Huntington’s disease
Name drugs for that used to treat HD that use following mechanisms:
- Vesicular amine transporter inhibitor [1]
- Antidopaminergic (antipsychotic) drugs [2]
- Vesicular amine transporter inhibitor: tetrabenazine
- Antidopaminergic (antipsychotic) drugs: haloperidol, olanzapine
Pharmacological management of Huntington’s disease
Name three antidepressant drugs used in the management of HD [3]
Antidepressant drugs: citalopram, fluoxetine, sertraline
Brain areas involved decision making & movement planning:
Which area of the brain is where conscious intentions are formed and we become aware of motor movement? [1]
Name another key function of this area? [1]
The posterior parietal cortex
Also provides a representation of the body and how it is situated in space
Broadmann areas 39 & 40
Prefrontal cortex:
Dorsolateral prefrontal cortex
What is this region of the pre-frontal cortex involved with? [3]
Planning of goal-directed behaviours AND simulating the consequences of plans
Initiating, inhibiting and swtiching executive behaviour: input to the basal ganglia about stop / start
Involved with:
Problem-solving
Goal-driven attention
Planning
Decision making
Working memory
dorsolateral prefrontal cortex:
Lesions in Brodmann area 46 affects which functions? [1]
Attention and working memory: affects ability to inhibit a response to a stimulus
Is damage to frontal eye fields a perceptual or motor problem? [1]
What is the effect of bilateral FEF lesion? [2]
In which direction does the eye move if have a frontal eye field defect? [1]
Frontal eye fields: motor problem:
Bilateral lesion: causes oculumotor apraxia - have to move head horizontally as they cannot move their eyes
Eye deviates towards the side of lesion
supplementory motor area:
Location:
Broadmann area? [1]
Lobe? [1]
Role? [2]
Location:
medial part of BA 6; frontal cortex
Role:
* Orgnaises actions that are internally guide according to preferences and goals: choosing objects
* Determines response threshold to initiate movement - the urgency of movement
* Response to start or stop a movement (interconnects to basal ganglia)
e.g which object to choose (in alignment with goals)
plan sequence of learned actions - e.g. playing piano
Which area of the brain is where conscious intentions are formed and we become aware of motor movement?
orbitofrontal (pre-frontal) cortex
posterior parietal cortex
medial pre-frontal cortex
dorso-lateral pre-frontal cortex
Which area of the brain is where conscious intentions are formed and we become aware of motor movement?
orbitofrontal (pre-frontal) cortex
posterior parietal cortex
medial pre-frontal cortex
dorso-lateral pre-frontal cortex
Which of the following areas are involved in Initiating, inhibiting and swtiching executive behaviour: input to the basal ganglia about stop / start
orbitofrontal (pre-frontal) cortex
posterior parietal cortex
medial pre-frontal cortex
dorso-lateral pre-frontal cortex
Which of the following areas are involved in Initiating, inhibiting and swtiching executive behaviour: input to the basal ganglia about stop / start
orbitofrontal (pre-frontal) cortex
posterior parietal cortex
medial pre-frontal cortex
dorso-lateral pre-frontal cortex
which of the following guides and monitos actions that are internally guided according to preferences and goals
orbitofrontal (pre-frontal) cortex
posterior parietal cortex
medial pre-frontal cortex
dorso-lateral pre-frontal cortex
which of the following guides and monitos actions that are internally guided according to preferences and goals
orbitofrontal (pre-frontal) cortex
posterior parietal cortex
medial pre-frontal cortex
dorso-lateral pre-frontal cortex
Which of the following modulates the degrees of cognitive control need to keep in behaviour in line with the goal
orbitofrontal (pre-frontal) cortex
posterior parietal cortex
medial pre-frontal cortex
dorso-lateral pre-frontal cortex
Which of the following modulates the degrees of cognitive control need to keep in behaviour in line with the goal
orbitofrontal (pre-frontal) cortex
posterior parietal cortex
medial pre-frontal cortex
dorso-lateral pre-frontal cortex
Which of the following modulates value for rewards and punishers
orbitofrontal (pre-frontal) cortex
posterior parietal cortex
medial pre-frontal cortex
dorso-lateral pre-frontal cortex
Which of the following modulates value for rewards and punishers
orbitofrontal (pre-frontal) cortex
posterior parietal cortex
medial pre-frontal cortex
dorso-lateral pre-frontal cortex
Extrapyramidal tracts:
Describe the course of the lateral vestibulospinal tract [1]
Which type of muscles does it synapse onto? [1]
Fibres descend ipsilaterally though the anterior funiculus of the same side of the spinal cord, synapsing on the extensor antigravity motor neurons: help maintain upright and balanced posture.
Extrapyramidal tracts:
Desribe the function and path of medial vestibulospinal tract
Function: Performs the synchronization of the movement of the eyes with the movement of the head so that eyes do not lag behind when the head moves to one side
Pathway: Descends bilaterally in the medial longitudinal fasciculus. Synapses with the excitatory and inhibitory neurons of the cervical spine
Describe the function and path of the rubrospinal tract [2]
Function: Controls muscle tone in flexor muscle groups; Inhibits extensor tone
Path:
- Arises from the red nucleus in the brainstem
- crosses at medulla
- terminates primarily in the cervical and thoracic portions of the spinal cord
Describe how rigidity occurs [1]
If have a lesion above the pons occurs, the inhibitory system is lost; extrapyramidal system becomes hyperactive
Where would damage occur for the following:
Decorticate posturing [1]
Decerebrate posturing [1]
Decorticate posturing:
* Damage to the corticospinal tract above or in midbrain
Decerebrate posturing
* Damage to the corticospinal tract at the level of upper brainstem, including corticospinal and rubrospinal tracts
Which of the following ensures that the eyes do not lag behind when the head moves to one side
rubrospinal tract
reticulospinal tract
lateral vestibulospinal tract
medial vestibulospinal tract
Which of the following ensures that the eyes do not lag behind when the head moves to one side
rubrospinal tract
reticulospinal tract
lateral vestibulospinal tract
medial vestibulospinal tract
Which of the following controls posture and balance
rubrospinal tract
reticulospinal tract
lateral vestibulospinal tract
medial vestibulospinal tract
Which of the following controls posture and balance
rubrospinal tract
reticulospinal tract
lateral vestibulospinal tract
medial vestibulospinal tract
Which of the following controls flexor muscle tone
rubrospinal tract
reticulospinal tract
lateral vestibulospinal tract
medial vestibulospinal tract
Which of the following controls flexor muscle tone
rubrospinal tract
reticulospinal tract
lateral vestibulospinal tract
medial vestibulospinal tract
Which extra-pyrimadal tract originates in the superior colliculus? [1]
tectospinal
Which of the following synapses on the extensor antigravity motor neurons
rubrospinal tract
reticulospinal tract
lateral vestibulospinal tract
medial vestibulospinal tract
Which of the following synapses on the extensor antigravity motor neurons
rubrospinal tract
reticulospinal tract
lateral vestibulospinal tract
medial vestibulospinal tract
