Intro to Brain Anatomy-Lateral View

Question 1

Central Nervous System

CNS

Answer 1

Composed of the brain and the spinal cord

Question 2

Peripheral Nervous System

PNS

Answer 2

Composed of all parts of the nervous system outside of the brain and the spinal cord.

Question 3

Name the places pointed in red

Answer 3

A) Cerebrum

B) Hypothalamus

C) Corpus Callosum

D) Thalamus

Question 4

What are the anatomical orientations?

Answer 4

• Anterior = rostral
• Posterior = caudal
• Superior = dorsal
• Inferior = ventral

and

• lateral = towards the side
• medial = towards the midline

Question 5

Place the orientations in the following image:

Answer 5

Question 6

Name the different ways to “slice” the brain

Answer 6

1. Sagittal
2. Coronal
3. Horizontal/Axial

Question 7

What does Sagittal mean?

Answer 7

You cut the brain following the natural division of the hemispheres.

Question 8

What does coronal mean?

Answer 8

You cut the brain along the x-axis where the x-axis goes from the anterior (front) part of the brain to the posterior (back) of the brain.

Question 9

What does horizontal/axial mean?

Answer 9

You cut the brain along the y-axis so from ventral (inferior) to dorsal (superior) part of the brain.

Question 10

Cerebrum

Answer 10

Voluntary movements, sensations, learning, remembering, thinking, emotion, consciousness.

Surface: Cerebral cortex

Question 11

Hypothalamus

Answer 11

Control of hunger, thirst, temperature and other visceral and bodily functions.

Question 12

Corpus Callosum

Answer 12

Band of fibres connecting the two hemispheres.

Question 13

Thalamus

Answer 13

Relay station to cortex for sensory information.

Question 14

Name the parts of the neuron and what they do.

Answer 14

Question 15

Who discovered the neuron?

Answer 15

Ramon y Cajal

Question 16

Name the two components of the brain and give a short description.

Answer 16

Grey matter: It is grey because of the density of the cell bodies of the neurons.

White matter: It is white because of the myelin sheath that covers the axons of the neurons.

Question 17

Myelin Sheath

Answer 17

Fatty substance to enhance conduction of electrical signal down the axon.

Question 18

True or False

You have myelin in the grey matter.

Answer 18

False, there are axons in the grey matter but they are so small that they do not need the myelin sheath.

Question 19

True or False

Dendrites are part of the white matter.

Answer 19

False

Question 20

Components of the grey matter

Answer 20

• Cerebral cortex:
  
  • Seat of higher cognitive processes
• Subcortical Structures:
  
  • More primitive controls
    
    • breathing
    • heart rate
    • alertness
    • etc…

Question 21

Cerebral Cortex

Answer 21

• Continuous sheet of tissue
  
  • not homogenous
    
    • cytoarchitectonic areas
• Has expanded over evolution
• Human cortex is the most convoluted of any primate brain
• Folded into:
  
  • suci
  • gyri
  • fissures
• 2/3 rds of the cortex is hidden within the suci and fissures
• Not random: Consistent patterns across individuals
• Certain sulci or gyri show strong relations to specific functional processes
  
  • They allow you to identify where certain functions take place in the brain

Question 22

Sulci

Answer 22

Are the valleys that you find in the brain where as fissures are deeper valleys.

Question 23

Gyri

Answer 23

The hills that you find in the wrinkles of the brain.

Question 24

How do we map cortical folds?

(before and now)

slides 15 to 17

Answer 24

• 19th century: it was possible to harden the brain with alcohol
  
  • relatively consistent patterns across individuals
  • Certain correlations with functional processes
  • Post-mortem
  • Surface analysis and restricted sample size
• Today:
  
  • Neuroimaging tools
    
    • many subjects
    • 3D
    • MRI
    • sulcus on the surface of the cortex to its depth
  • Petrides lab

Question 25

Lobes of the Brain

Answer 25

• Frontal lobe (red)
• Parietal lobe (beige)
• Temporal lobe (blue)
• Occipital lobe (green)
• (Insular lobe (purple))
• (Limbic lobe (yellow))

Question 26

Frontal Lobe

Answer 26

• Voluntary motor control
• Working memory functions
• Broca’s area for speech production

Question 27

Parietal Lobe

Answer 27

• Somatosensory processing (sensations anywhere)
• Dorsal stream of vision where
• Reading functions
• Writing functions
• Spatial processing

Question 28

Occipital Lobe

Answer 28

• Visual Processing

Question 29

Temporal Lobe

Answer 29

• Auditory processing
• Wernicke’s area for language comprehension
• Ventral stream of vision what
• Smell processing
• Memory consolidation

Question 30

Which sulci establish the 4 lobes?

Answer 30

• Central Sulcus
• Parieto-occipital Fissure
• Pre-Occipital notch
• Lateral sulcus (Sylvian fissure)

Question 31

Suci and Gyri in Frontal Lobe

Answer 31

• Central sulcus
• Pre-central Gyrus
• Superior Pre-central sulcus
• Inferior Pre-central sulcus
• Superior Frontal Gyrus
• Superior Frontal Sulcus
• Medial Frontal Sulcus
• Inferior Frontal Sulcus
• Inferior Frontal Gyrus
• Horizontal Ramus (of the lateral fissure)
• Intermediate Frontal Sulcus

Question 32

Sulci and Gyri in Parietal Lobe

Answer 32

• Central Sulcus
• Post-central Gyrus
• Superior Post-central Sulcus
• Inferior Post-central Sulcus
• Superior Parietal Lobule
• Intraparietal Sulcus
• Supresmarginal Gyrus
• Posterior Ascending Ramus (of lateral fissure)
  
  • down
• Superior Temporal Sulcus
  
  • up-right
• Angular Gyrus
• Parieto-Occipital Fissure

NOTE:

• Inferior Parietal Lobule
  
  • Supramarginal Gyrus
  • Angular Gyrus

Question 33

Suldi and Gyri in Temporal Lobe

Answer 33

• Sylvian Fissure
• Superior Temporal Gyrus
• Superior Temporal Sulcus
• Middle Temporal Gyrus
• Inferior Temporal Sulcus
• Inferior Temporal Gyrus

Question 34

Peri-central Region

Answer 34

The peri-central region is composed by:

• Pre-central Gyrus
• Post-central Gyrus
• Central Sulcus

Question 35

What did Penfield do?

Answer 35

• Dr. Penfield stimulated the Peri-central region and mapped the somatotopic organization of these gyri.
  
  • Pre-central gyrus = Motor cortex (M1)
  • Post-central gyrus = Somatosensory cortex (S1)

Question 36

Which gyrus is also called the Motor Cortex?

Answer 36

• Pre-central gyrus
  
  • Voluntary control of the opposite side of the body (compared to the hemisphere)

Question 37

Which gyrus is called the Somatosensory cortex?

Answer 37

• Post-central gyrus
  
  • Sensations coming from the opposite side of the body (depending on the hemisphere)

Question 38

What does Homunculus mean?

Answer 38

Little man

Question 39

Name the parts of the Inferior Frontal Gyrus

Answer 39

• Pars Triangularis
• Pars Orbitalis
• Pars Opercularis