Intro to Neuroanatomy

Question 1

What are the 3 parts of the brain

Answer 1

• Forebrain
• Midbrain (Mesencephalon)
• Hindbrain (Rhombenchephalon)

Question 3

What 2 structures make up the Forebrain (everything sitting on top of brainstem)

Answer 3

• Cerebrum (most superficial, looks like cauliflower)

- Diencephalon (very deep)

Question 4

What are the components of the Diencephalon

Answer 4

• Hypothalamus

- Thalamuses (1 on each side)

Question 5

What are the 3 parts of the Brainstem superiorly to inferiorly?

Answer 5

• Midbrain
• Pons (Bulbous looking)
• Medulla (becomes spinal cord once it passes through Foramen magnum)

Question 6

Where is the Cerebellum found?

Answer 6

Just behind Brainstem

Question 7

Describe the Cortex of the Cerebrum

What layer is deep to this layer?

Answer 7

• Grey matter
• High density of cell bodies
• A few mm in thick
• Darker in colour than deeper White Matter
• White Matter (densely packed myelinated axons)

(Myelin is fatty thus white colour)

Question 8

What is a Fissure of the brain?

Which fissure separates brain into left and right fissures?
What is the other important fissure?

Answer 8

A dip in the cortex, deeper than the Sulci

• Longitudinal Fissure
• Lateral/ Sylvian Fissure (Not as deep as longitudinal fissure)

Question 9

Is the cortex or white matter responsible for conscious awareness and motor actions?

Answer 9

Cortex/ Grey Matter

Question 10

What sulcus marks the posterior margin of the Frontal Lobe?

What lobe lies posterior to this sulcus

Answer 10

Central Sulcus, which lies anterior to Parietal Lobe

Question 11

What sulcus lies between the Parietal and Occipital lobe?

Answer 11

Parietal-occipital Sulcus

Question 12

What lies between the Temporal Lobe and the Parietal and Frontal Lobes

Answer 12

Sylvian/ Lateral Fissure or Lateral Sulcus

Question 13

What is the Corpus Callosum?

Answer 13

A bridge of White Matter between left and right hemispheres allowing communication between them

Question 14

Below and Medial to the Corpus Callosum is a cavity filled with CSF.

What membranous structure covers it laterally

Answer 14

The Septum Pellucidum

Question 15

Due to the Neuraxis, standard anatomical terminology doesn’t apply to the brain.

What words do we use to say;

• Anterior
• Posterior
• Superior
• Inferior

Answer 15

A: Rostral (towards nose)

P: Caudal

S: Dorsal

I: Ventral

Question 16

What are the centres and nuclei of the Midbrain part of the Brainstem responsible for?

Answer 16

• Co-ordinating eye movement, pupil reflex response to light

Question 17

What are the functions of the Pons?

Answer 17

• Feeding (Trigeminal nerve comes off of here)

- Sleep control

Question 18

What are the functions of the Medulla?

Answer 18

• Cardiorespiratory functions

Question 19

List 5 functions of the Frontal Lobe

Answer 19

• Voluntary motor control
• Speech production
• Social behaviour
• Impulse control
• Higher cognition (planning, thinking)

Question 20

Which part of Frontal Lobe is associated with Voluntary Motor Control?

What is this structure also called?

Answer 20

Pre-central Gyrus (Rostral to Central Sulcus)

The Primary Motor Cortex

Question 21

List 6 functions of Temporal Lobe

Answer 21

• Language
• Emotion
• Long term memory
• Special senses (Smell, Hearing, Taste)

Question 22

List 2 functions of the Parietal Lobe

Answer 22

• Spatial awareness

- Somatosensory (Not the special senses) perception (Touch, temperature, vibration etc.)

Question 23

Which part of the Parietal lobe is responsible for Somatosensory perception

What is this structure also called?

Answer 23

Post-central Gyrus (Caudal to Central Sulcus)

The Primary Somatosensory Cortex

Question 24

List 1 function of the Occipital Lobe

Answer 24

• Visual perception

Question 25

List 1 function of the Cerebellum

Answer 25

• Co ordination of motor movements and motor learning

Question 26

What is the Uncus?

What do we receive from here?

Answer 26

The most medial part of the Temporal Lobe (Visible from inferior view)

• This is where we receive Olfactory information (sense of smell)

Question 27

What is an Uncal herniation?

Answer 27

High intracranial pressure causes Uncus to herniate through the Tentorial Notch into the Posterior Cranial Fossa

Question 28

In an Uncalled herniation, which nerve can get compressed/ irritated by the Uncus?

Answer 28

Cranial Nerve 3 (Oculomotor nerve)

Question 29

Head and neck structures are controlled by what region of the Primary Motor Cortex

Answer 29

Lateral aspect

As we go more medial, the trunk-> Hands-> Feet are controlled

Question 30

A lesion in the Right Primary Motor Cortex would cause symptoms in the Left Arm.

Describe the path of a Motor Neuron starting in the Right Primary Motorcortex, causing this symptom

Answer 30

• Runs through CNS of brain to enter right Brainstem
• Runs through right Pons
• At level of Medulla, neuron crosses (decussates) to opposite side
• Runs down spinal cord, synapses with motor part of left spinal nerve innervating the muscles of the limb

(Sensory neurons also cross sides when coming up to brain)

Question 31

What is the function of the Thalamus?

Answer 31

Act as relay stations for all the sensory information coming up to brain

Question 32

Spinal nerves have Uni-cortical Contralteral Control

What does this mean?

Answer 32

Cortical control of limb movement is from 1 Primary Motor Cortex, which is Contralateral

Question 33

Where do the Cranial Nerves supplying the Head and Neck muscles cross sides? (Decussate)

Answer 33

At the level of the nuclei onto which they communicate/ are going to synapse

Question 34

Most cranial nerves supplying the head and neck muscles have Dual Cortical Control.

What does this mean?

Answer 34

• Have a Primary/ Dominant input from the Contralateral Primary Motor Cortex
• Most have a Secondary/ Back-up input from the Ipsilateral Primary Motor Cortex

Question 35

Name a Cranial Nerve that is an exception to the rule of Dual Cortical Control

Answer 35

Facial nerve (Ipsilateral face drooping)