Intro

Question 1

What is the difference in regeneration ability of the CNS and PNs? What is each made up of?

Answer 1

CNS can’t regenerate - cerebral hemispheres, brainstem, cerebellum, spinal cord

PNS can - dorsal & ventral roots, spinal nerves, peripheral nerves (+ cauda equina)

Question 2

What are grey and white matter?

Answer 2

Grey - cell bodies and dendrites, highly vascular (axons to communicate with white matter)

White - composed of axons + supporting cells e.g. oligodendrocytes, fatty myelin

Question 3

What is the PNS system equivalents yo grey and white matter?

Answer 3

Grey - ganglion (collection cell bodies)

White - peripheral nerve

Question 4

What is a funiculus?

Answer 4

Segment of white matter containing multiple distinct tracts - impulses travel in multiple directions

(Found in spinal cord white matter)
Dorsal, ventral and lateral

Question 5

What is a tract?

Answer 5

Anatomically and functionally defined white matter pathway connecting 2 distinct regions of grey matter. Impulses travel in one direction.

(Found in the spinal cord white matter)

Question 6

What is a fasciculus?

Answer 6

Subdivision of a tract supplying a distinct region of the body

(Found in spinal cord white matter)

Question 7

How is grey matter in the spinal cord organised?

Answer 7

Into cell columns with particular numbers (Rexed’s laminae)

Motor neurones arise from multiple segments and form a distinct population of neurones in CNS (a nucleus)

Question 8

What are the three fibres found in the CNS?

Answer 8

Association fibres - connect close regions in cerebral cortex (within same hemisphere), short

Commissural fibres - connect contralateral hemispheres (L↔️R)

Projection fibres - connect hemispheres ↔️ cord/ Brainstem

Question 9

Define a nucleus

Answer 9

(Grey matter)

Collection of functionally related cell bodies

Question 10

Define cortex

Answer 10

(Grey matter)

A folded sheet of cell bodies found on the surface of a brain structure (1-5mm thick)

Question 11

Define fibre

Answer 11

(White matter)

Term relating to an axon in association with its supporting cells (e.g. oligodendrocytes) used synonymously with axon

Question 12

What are parts of the brain stems general functions?

Answer 12

Midbrain (mesencephalon) - eye movements and reflex responses to sound and vision

Pons (mesencephalon) - feeding and sleep

Medulla (myelencephalon) - cardiovascular and respiratory centres, contains a major motor pathway (medullary pyramids)

Question 13

What is the lateral/ Sylvia fissure?

Answer 13

Separates temporal from frontal/ parietal lobes

Question 14

What separates the parietal from occipital lobe?

Answer 14

Parieto-occipital sulcus

Question 15

What is the calcarine sulcus?

Answer 15

Primary visual cortex surrounds it

Question 16

What is the Uncus?

Answer 16

Part of the temporal lobe that can herniate compressing the midbrain, important olfactory role

Inferior brain

Question 17

What are the medullary pyramids?

Answer 17

Location of descending motor fibres

Inferior brain

Question 18

What is the parahippocampal gurus?

Answer 18

Key cortical region for memory encoding (make associations)

Inferior brain

Question 19

Key features of inferior brain from anterior to posterior

Answer 19

Optic chiasm
Uncus
Parahippocampal gurus
Medullary pyramids

Question 20

What is the cingulate gurus important for?

Answer 20

Cortical area important for emotion and memory

Question 21

What is the fornix?

Answer 21

Major output pathway from hippocampus

Question 22

What is the tectum?

Answer 22

Dorsal part of the midbrain involved in involuntary responses to auditory and visual stimuli

Question 23

Explain the production and circulation of cerebrospinal fluid

Answer 23

Cavities in the brain are called brain ventricles these contain choroid plexus (makes 600-700ml CSF/ day)

CSF- metabolic and mechanical functions

CSF circulates through ventricular system & subarachnoid space before being reabsorbed at arachnoid granulations - lots in superior Sagittal sinus (and some other sites)

(2 lateral ventricles -> interventricular foramen -> 3rd ventricle (between thalamus) -> cerebral aqueduct -> foramen of Luschka/ magendie (majority CSF drainage) + some into central canal

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