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Flashcards in Neuroanatomy Deck (89)
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1
Q

What are the components of the CNS?

A

Brain and spinal cord

2
Q

What are the components of the PNS?

A

12 pairs of cranial nerves

31 pairs of spinal nerves and branches

3
Q

What makes up the brainstem?

A

Midbrain, pons and medulla oblongata

4
Q

What makes up the diencephalon?

A

Thalamus + hypothalamus

5
Q

What are the two principal cells of the CNS?

A

Neurons and glial cells

6
Q

What are the four major types of glial cells?

A

Astrocytes, oligodendrocytes, microglia, ependymal cells

7
Q

What is the function of astrocytes?

A

Support, maintenance of the BBB and environmental homeostasis

8
Q

What is the function of oligodendrocytes?

A

Produce myelin in the CNS

9
Q

What is the function of microglia cells?

A

Antigen presentation and phagocytosis

10
Q

What is the function of ependymal cells?

A

Ciliated columnar epithelium which lines the ventricles of the brain

11
Q

What are the lumpy bits of the brain called and what are the indents called?

A

Gyri (lumps), sulci(indents), fissures (deeper than sulci)

12
Q

What is the general location of white and grey matter in the brain and the spinal cord ?

A

Grey matter is mostly outside and white is mostly inside. (BRAIN)

White matter is outside and grey matter is inside. (SPINAL CORD)

13
Q

What is white and grey matter composed of?

A

White matter mostly consists of myelinated axons and their support cells

Grey matter mostly consists of neurons, cell processes, synapses and support cells

14
Q

Describe the location of the frontal lobe of the cerebral hemisphere of the brainin relation to sulci

A

Anterior to the central sulcus and superior to the lateral sulcus

15
Q

Describe the location of the parietal lobe of the cerebral hemisphere in relation to sulci

A

Posterior to the central sulcus, superior to the lateral sulcus and anterior to the parieto-occipitaq sulcus

16
Q

Describe the location of the occipital lobe of the cerebral hemisphere in relation to sulci

A

Posterior to the parietal-occipital sulcus

17
Q

Describe the location of the temporal lobe of the cerebral hemisphere in relation to sulci

A

Inferior to the lateral sulcus

18
Q

What is the important role of the insular lobe of the brain?

A

Plays a role in the patient’s experience of pain

NB this lobe can only be seen when the brain is dissected

19
Q

What are the three layers of the meninges from superficial to deep?

A

Dura matter, arachnoid matter, pia matter

20
Q

What two things make up the arachnoid matter?

A

Subarachnoid space and CSF fluid

21
Q

What is the enteric nervous system?

A

The nervous system of the digestive system - made up of the myenteric plexus and the submucosal plexus

22
Q

The dural venous sinuses of the brain drain into which vein?

A

Internal jugular vein

23
Q

Where are motor neurones in the spinal cord?

A

Anterior (ventral) horns

24
Q

Which cell types lines the ventricles of the brain?

A

Ependymal cells

25
Q

Which two things make up the lentiform nucleus?

A

Putamen and globus pallidus

26
Q

What is the interthalamic adhesion?

A

The touching point between the two halves of the thalamus

27
Q

What is the new name given to the spinal cord after it terminates at L2?

A

Conus medullaris

28
Q

After the spinal cord terminates at the conus medullaris, it continues as a thin connective tissue cord, what is this called?

A

The filum terminale - this is anchored to the dorsal of the coccyx

29
Q

The spinal cord is suspended in the canal by which ligament?

A

The denticulate ligament

30
Q

A small central canal extends the length of the spinal cord. Rostrally it is continuous with which structure?

A

It is continuous with the 4th ventricle of the brian

Caudally it is blind ending

31
Q

What is present at spinal levels T1 - L2 which isn’t present at other levels?

A

At T1-L2 there are small lateral horns (aswell as the usual A&P horns) which contain the preganglionic sympathetic neurons (THORACOLUMBAR OUTFLOW)

32
Q

Describe the arterial supply to the spinal cord

A

Vertebral arteries give rise to 1 anterior and 2 posterior longitudinal arteries

Segmental arteries

Radicular arteries

33
Q

Describe the venous drainage of the spinal cord

A

Longitudinal and segmental veins drain the spinal cord

34
Q

What is the epidural space?

A

The space between dura and bone in the spinal canal.

It contains fat and the anterior and posterior epidural venous plexuses.

35
Q

White matter occupies a smaller proportion of the cord as it descends from cervical to sacral. T/F

A

True

36
Q

At which points is the spinal cord largest?

A

The spinal cord is larger in cervical and lumbar regions

37
Q

What are the names of the ascending spinal cord tracts?

A

The dorsal column/ medial lemniscus system (DCML)

Spinothalamic tract

38
Q

The dorsal column/ medial lemniscus system carries what information?

A

This is one of the ascending sensory tracts which carries information about fine touch and proprioception

39
Q

Where do the fibres cross in the dorsal column/medial lemniscus system ascending tract?

A

The fibres cross over in the medulla

40
Q

The spinothalamic tract carries what information?

A

This is one of the ascending sensory tracts which carries information about pain, temperature and deep pressure

41
Q

Where do the fibres cross in the spinothalamic tract?

A

The fibres cross segmentally

42
Q

What are the names of the descending spinal cord tracts?

A

PYRAMIDAL TRACTS
Corticospinal tract
Corticotubular tract

EXTRAPYRAMIDAL TRACTS
Tectospinal tract
Reticulospinal tract
Vestibulospinal tract

43
Q

The corticospinal tract is one of the descending motor tracts. What motor functions is it involved in?

A

Fine and precise movements, especially of the distal limb muscles (e.g digits)

NB corticospinal - starts in the cortex and ends in the spine

44
Q

Where do most of the fibres cross in the corticospinal descending tract?

A

Lateral CST - Most of the fibres cross at the decussation of the pyramids (in the medulla)

Ventral CST - fibres cross segmentally (still cross but just at random points)

45
Q

What is meant by ‘decorticate posturing’ and which pathway is responsible?

A

Spastic paralysis with hyperFLEXION of the upper limbs

Caused by lack of control of the descending corticospinal tract e.g due to infarct

46
Q

Which of the descending tracts is thought to mediate reflex head and neck movement due to visual stimuli?

A

Tectospinal tract

(starts in the tectum(roof of the midbrain) and ends in the spinal cord)

Only serves the cervical regions

47
Q

Which descending tract receives input from almost all parts of the CNS and has many functions?

A

The reticulospinal tract

48
Q

With reference to the reticulospianl tract, what movements do fibres originating in the pons Vs the medulla facilitate?

A

Fibres originating in pons facilitate extensor movements and inhibit flexor movements, while those originating in the medulla do the opposite.

49
Q

What is the function of the vestibulospinal tract?

A

Posture and balance

NB this tract doesn’t cross over - it is ipsilateral

50
Q

What is ‘decorticate rigidity’? and which pathway is responsible?

A

HyperEXTENDED spastic paralysis

Caused by lack of control of the vestibulospinal tract E.g due to lesions of the brainstem at the midbrain

51
Q

What term is used to describe crossing over in the spinal tract?

A

Decussation

52
Q

Describe Brown Sequard Syndrome

A

Brown-Séquard syndrome is caused by damage to one half of the spinal cord

Results in paralysis and loss of proprioception on the SAME SIDE as the injury or lesion and loss of pain and temperature sensation on the OPPOSITE SIDE as the lesion.

53
Q

What are the three lobes of the cerebellum?

A

Anterior lobe, posterior lobe, flocculonodular node

*Posterior lobe is the largest

54
Q

Describe the location of the cerebellum

A

The cerebellum sits in the posterior cranial fossa and is subtentorial (inferior to the tentorium cerebellum)

55
Q

How is the cerebellum attached to the brainstem?

A

The cerebellum is attached to the brainstem via 3 peduncles (stalks) - superior, middle and inferior

56
Q

Describe the locations of grey and white matter in the cerebellum

A

Outer grey matter with an inner white matter core. There is also some deep grey matter.

57
Q

What are the 3 cell layers of the cerebellar cortex from outer to inner?

A

Molecular layer, purkinje layer, granule cell layer

58
Q

What are the 3 main functional divisions of the cerebellum and what role do they each play?

A

Pontocerebellum - planning and carrying out movements (particularly in distal limb movements)

Spinocerebellum - postural control

Vestibulocerebellum - balance

59
Q

What is cerebellar ataxia?

A

When the cerebellum becomes inflamed or damaged

E.g due to alcohol intoxication

Affects movement

60
Q

What are the functions of basal ganglia?

A

Facilitate purposeful movements

Inhibit unwanted movements

Posture and muscle tone

61
Q

What are basal ganglia?

A

Masses of grey matter located near the base of each cerebral hemisphere

62
Q

What 5 structures make up basal ganglia?

A
Caudate nucleus 
Putamen 
Globus pallidus 
Subthalamic nucleus 
Substantia nigra
63
Q

How do basal ganglia work with the motor cortex to enhance normal movement or suppress unwanted movement?

A

Direct pathway; enhances outflow from the thalamus

Indirect pathway; inhibits outflow from the thalamus

64
Q

Unilateral cerebellar lesions affect which side of the body?

A

IPSILATERAL SIDE

damage to one side of the cerebellum results in impaired function on the same side of the body

65
Q

Unilateral basal ganglia lesions affect which side of the body?

A

CONTRALATERAL SIDE

damage to basal ganglia on one side results in impaired function on the opposite side of the body

66
Q

Lesions of basal ganglia cause what kind of motor signs?

A

Changes in muscle tone

Dyskinesias (involuntary movements)

67
Q

Dyskinesias is a term used to describe abnormal/ involuntary movements. Give some examples of types of dyskinesias

A

Tremor (sinusoidal movements)

Chorea (asymmetrical movements)

Myoclonus (muscle jerks)

68
Q

Name some disorders associated with basal ganglia

A

Parkinson’s

Huntington’s chorea

69
Q

What is the basic pathology behind Parkinson’s disease?

A

Degeneration of dopaminergic neurons of the substantial nigra

70
Q

What are the clinical signs of Parkinson’s?

A

Akinesia, rigidity, resting tremor

71
Q

What is the basic pathology behind Huntington’s Disease?

A

Progressie degeneration of the basal ganglia and cerebral cortex

72
Q

What are the clinical signs of Huntington’s?

A

Chorea and progressive dementia

73
Q

What is unique about the optic nerve?

A

It is myelinated by oligodendrocytes, meaning it is essentially a bit of CNS

74
Q

Describe the location of the nerve fibres in CN I (olfactory nerve) with relation to the olfactory bulb and tract

A

The olfactory tract gives rise to the olfactory bulb which sits in the cribriform plate, the nerve fibres dangle down into the nasal cavity

(the nerve fibres are in contact with the outside world - they therefore die off over time)

75
Q

Which cranial nerves are purely motor?

A

III, IV, VI, XI, XII

76
Q

Where does the spinal accessory nerve arise from?

A

The cervical spinal cord

77
Q

Which cranial nerves have mixed modalities?

A

CN V, VII, IX and X

78
Q

The sensory nucleus of the trigeminal nerve has 3 parts; what are they and what are their functions?

A

Mesencephalic nucleus - proprioception info from chewing muscles/ teeth/ jaw

Pontine trigeminal nucleus - discriminative touch and vibration

Spinal nucleus - pain and temp

79
Q

Some brainstem nuclei are shared by more than one CN

The solitary nucleus for taste and sensory info is shared by which nerves?

A

CN VII, IX and X

80
Q

Some brainstem nuclei are shared by more than one CN

Superior and inferior salivary nuclei are shared by which nerves?

A

CN VII and IX

81
Q

Some brainstem nuclei are shared by more than one CN

Nucleus ambiguus are shared by which nerves?

A

CN IX and X

82
Q

Which descending spinal cord tract gives motor input to the cranial nerves?
(CN V, VII, X and XII)

A

Corticotubular tract

83
Q

Where do fibres carrying low vs high frequency sound end in the auditory cortex?

A

Low frequency sound - end in the anterolateral part of the auditory cortex

High frequency sound end in the posteromedial part of the auditory cortex

84
Q

What is meany by ‘aphasia’?

A

Inability to use language

85
Q

Describe what happens when there is damage to Broca’s area of the brain

A

Difficulty PRODUCING language (comprehension is ok)

Broca’s area of the brain manufactures speech

86
Q

Describe what happens when there is damage to Wernicke’s area of the brain

A

Difficulty COMPREHENDING language

Wernicke’s area of the brain interprets speech

87
Q

Superior to the cochlea input is BILATERAL. T/F

A

True - this means that any problems with the brainstem etc would cause bilateral hearing loss, whereas problems with the cochlea would cause unilateral hearing loss.

88
Q

Describe the two types of eye movements

A

Tracking movements

  • E.g following your finger
  • smooth movement

Movements of command

  • E.g scanning a room of people
  • saccadic jumpy movement
89
Q

What are the three types of fibres in the white matter of the cerebral hemispheres?

A

Association fibres
(connect cortical sites within the same hemisphere)

Commissural fibres (connect R&L hemispheres)

Projection fibres 
(connect hemispheres to deeper structures e.f thalamus and brainstem)