Tracts, basal ganglia and brainstem Flashcards Preview

Neuro > Tracts, basal ganglia and brainstem > Flashcards

Flashcards in Tracts, basal ganglia and brainstem Deck (49):
1

Give 3 lower motor neurone lesion signs.

Fasciculation
Atrophy
Hypotonia
Hyporeflexia
No Babinski sign

2

Give 3 (non-initial) upper motor neurone signs.

Hyperreflexia
Hypertonia - spasticity
Positive Babinski sign

3

How does a UMN lesion initially present?

Flaccid paralysis

4

What is the internal capsule?

White matter carrying descending motor fibres from cortex.
It is found between the thalamus and caudate on one side and the globus pallidus and putamen on the other.
The fibres within it are not randomly arranged.
- Genu = head & face fibres (corticonuclear)
- Posterior limb = corticospinal tract fibres

5

What is the blood supply to the internal capsule?

Lenticulostriate arteries of the MCA

6

Why do UMN lesions lead to spasticity?

Loss of descending inhibition on LMN

7

What is the triad of signs characteristic of Parkinson's disease?

Tremor, rigidity, bradykinesia

8

Which basal ganglia is affected by Parkinson's

Substantia nigra pars compacta

9

What is the treatment for Parkinson's?

L-DOPA
+ CARBIDOPA (to inhibit L-DOPA => dopamine in the periphery)

10

What do we give Parkinson's patient carbidopa as well as L-DOPA?

Because if don't give carbidopa, lots of the L-DOPA given would be converted to dopamine in the periphery. But we need dopamine in the brain! So inhibit peripheral conversion by AADC by giving carbidopa.

11

What is the red nucleus?

Mickey's eyes.
Important landmark in the midbrain it is involved in MOTOR control.
(without it, coarse tremour)

12

What are the crus cerebri?

- Mickey's ears
- Midbrain structures.
- Part of the cerebral peduncle containing descending motor fibres.
- Join cerebrum to midbrain.

13

What forms Mickey's nose?

The occulomotor nucleus.
- contains cell bodies of LMNs that travel CN3 to the eyeball

14

What is the superior colliculus?

Mickey's chin
Involved in reflex actions relating to the visual system.

15

What is the inferior colliculus?

Structure involved in reflex actions relating to the auditory system.

16

What is the periaqueductal grey matter?

Also called central grey matter
Important role in pain regulation and micturition.

17

In the internal capsule where would the fibres representing the lower limbs be found?

Posterior limb of internal capsule

18

The corticospinal tract has different names as it travels from cortex to periphery. What are these names?

1. Corona radiata
2. Internal capsule
3. Cerebral peduncles
4. Corticospinal tract

19

What is the corticobulbar tract?

It is a motor pathway from cortex to medullary pyramids.
It carries the UMNs (motor functions) of Cranial Nerves EXCEPT CN3.
(ie. as opposed to corticospinal which connects with spinal nerves)

20

What is spinal shock?

It describes the initial flaccid paralysis and hyporeflexia resulting from a UMN lesion.
=> signs of spinal shock can make one think it's a LMN lesion!

21

What is Cushing's reflex? (triad)

It is a physiological response to raised ICP.
1. Increased BP
2. Bradycardia
3. Decreased RR

22

On a stroke ward a patient has only eaten the right half of his dinner. What is this called?

neglect

23

Which lobe is most likely affected in a patient showing signs of neglect?

Parietal. Because the parietal lobe is responsible for spatial awareness, directing attention to the external world.

24

Are the visual fields affected in neglect?

No. visual fields are intact

25

Patient experiences the smell of organise before a seizure, where is the causative lesion most likely to be?

Temporal lobe

26

Patient has tumour in left temporal lobe resected. Which vial defect might result?

Right superior homonymous quadrantanopia.

27

What is Broca's area responsible for?

Production of speech

28

What is Wernicke's area responsible for?

Understanding speech

29

What is the name of the structure linking Wernicke's to Broca's?

Arcuate fasciculus

30

How does a Broca's aphasia present?

Stoccato speech. Able to understand question and reply but difficult to produce speech.

31

How does Wernicke's aphasia present?

Lots of non-sense. Able to speak lots of words, but cannot answer a question as cannot understand speech.

32

In which lobe does Broca's area sit?

Frontal lobe of dominant hemisphere (left ++)

33

In which lobe does Wernicke's area sit?

Temporal lobe of dominant hemisphere (left ++)

34

What is implicit memory?

Memory for unconsciously mediated behaviours such as complex motor tasks (playing guitar, driving).

35

Which brain structure is crucial for consolidation of implicit memory?

Cerebellum

36

What structure can uncial herniation compress?

CN3

37

What clinical sign of uncial herniation might we see?

Pupillary dilation (lost parasympathetic, so unopposed sympathetic)

38

Which 3 CNS herniations can occur when ICP is raised?

1. Uncal (transtentorial)
2. Tonsillar
3. Subfalcine

39

What is tonsillar herniation?

When the cerebellar tonsils are pushed downwards through the foramen magnum.
Increased pressure on the brainstem can result in dysfunction of the centers in the brain responsible for controlling respiratory and cardiac function

40

What is a subfalcine herniation?

The innermost part of the frontal lobe (cingulate gyrus) is pushed under part of the falx cerebri.

41

Rapid onset dementia in a young person might be suggestive of which condition?

Prion disease

42

What type of dementia presents with Parkinsonian features?

Lewy Body

43

What is Pick's disease?

It is the formation of Pick's bodies from Tau proteins especially in frontal and temporal lobes

44

Name 2 microscopical features of Alzheimer's

1. Amyloid beta plaques
2. Neurofibrillary tangles

45

Infarcts affecting which vessel tend to cause pure motor strokes?

a Lenticulostriate stroke

46

Infarcts affecting which vessel tend to cause locked-in syndrome?

Basilar artery

47

What two structures does the posterior communicating artery connect?

Posterior circulation (PCA) to Anterior circulation (ICA/MCA)

48

What two vessels are joined up by the anterior communicating artery?

Anterior cerebral arteries

49

Which two vessels come together to form the basilar artery?

Vertebral arteries