Neuro 1.1 Introduction To Neuroanatomy

Question 1

What are the elements of the CNS?

Answer 1

Cerebral hemispheres
Brainstem and cerebellum
Spinal cord

Question 2

What are the elements of the PNS

Answer 2

Dorsal and ventral roots 
Spinal nerves
Peripheral nerves
Ganglia 
*Cauda equina has dorsal and ventral roots, it is in vertebral cabal but isn't CNS

Question 3

What is grey matter composed of?

Answer 3

Cell bodies and dendrites
Highly vascular
Axons (allow communication with white matter)

Question 4

What is white matter composed of? Why is it white?

Answer 4

Composed of axons and supporting cells

It is white because of fatty myelin

Question 5

Describe the organisation of grey and white matter at a spinal level

Answer 5

• Cord has central core of grey matter and outer shell of white matter
• Each segment comments with a spinal (mixed nerve) via dorsal and motor roots

Question 6

What is a funiculus? What type of matter is it?

Answer 6

• Segment of white matter containing multiple distinct tracts
• Impulses travel in multiple directions
• Eg: dorsal funiculus

Question 7

What is a tract? What type of matter is it?

Answer 7

White matter

• Anatomically and functionally defined white mater pathway connecting 2 different regions of grey matter
• impulses travel in 1 direction

Question 8

What is a fasciculus? What type of matter is it?

Answer 8

White matter

• Subdivision of a tract supplying a distinct region of body
• Eg Fasciculus gracilis

Question 9

Describe the basic organisation of grey matter

Answer 9

• Grey matter is organised into cell columns
• Dorsal horn = sensory function
• Ventral horn = motor function

Question 10

What is a nucleus (grey matter)

Answer 10

-Collection of functionally related cell bodies

Question 11

What is a fibre? What type of matter?

Answer 11

• White matter

- term relating to axon in association with supporting cells (eg oligodendrocyte) - used synonymously with ‘‘axon’’

Question 12

What is an association fibre?

Answer 12

• White matter

- Connects cortical regions within same hemisphere

Question 13

What is a commissure lady fibre?

Answer 13

• White matter

- Connects left and right hemispheres or cord 1/2s

Question 14

What is a projection fibre?

Answer 14

• White matter

- Connect the cerebral hemispheres with the cord/brainstem and vice versa

Question 15

The the functions and another name for the midbrain

Answer 15

• Functions: eye movement and reflect responses to sound and vision
• Mesencephalon

Question 16

What are the functions of the medulla?

Answer 16

• CVS and resp centres

- Medullary pyramids: major motor pathway

Question 17

On the picture in notes, identify the following. What are their functions?

• Central sulcus
• Pre central gyrus
• Post central gyrus
• Lateral/Sylvian fissure
• Parieto-occipital sulcus
• Calcarine sulcus

Answer 17

• Central sulcus: separates frontal and parietal lobes
• Pre central gyrus: primary motor cortex
• Post central gyrus: primary sensory cortex
• Lateral/Sylvian fissure: separates temporal/frontal lobes
• Parieto-occipital sulcus: separates parietal/occipital lobes
• Calcarine sulcus: primary visual cortex surrounds the sulcus

Question 18

On the diagram label the following. What are their functions?

• Optic chiasm
• Uncus
• Medullary pyramids
• Parahippocampal gyrus

Answer 18

• Optic chiasm: site of cross over for visual fibres
• Uncus: part of temporal lobe that can herniate and compress the midbrain + important for olfaction (lambic system)
• Medullary pyramids
• Parahippocampal gyrus: key cortical region for memory encoding

Question 19

On the diagram label the following and give their function

• Corpus callosum
• Thalamus
• Cyngulate gyrus
• Hypothalamus

Answer 19

• Corpus callosum: fibres connecting the 2 cerebral hemispheres
• Thalamus: sensory relay station, projects into sensory cortex
• Cyngulate gyrus: cortical area important for emotion and memory
• Hypothalamus: Essential centre for homeostasis

Question 20

Label the following structures on the diagram and state their function/importance

• Fornix
• Tectum
• Cerebellar tonsil

Answer 20

• Fornix: major output pathway from the hippocampus
• Tectum: dorsal part of midbrain involved in involuntary responses to auditory and visual stimuli
• Cerebellar tonsil: part of cerebellum that can herniate and compress the medulla

Question 21

What is the ventricular system?

Answer 21

Series of hollow tubes formed by the folding of the brain

- they each have a choroid plexus and produce CSF fluid

Question 22

How is CSF drained from the brain?

Answer 22

• Central canal: very narrow
• 2 Lateral apertures: into sub arachnoid space
• Median aperture: CSF emerges into sub-arachnoid space
• Last two bathe the brain in CSF –> CSF via arachnoid granulations, goes into dural Venus sinuses and granulations in the spine