Brain and Cranial Nerves

1. Activity 7:
Nervous System Histology, Brain, &
Cranial Nerves
Chapters 14 & 15 – McKinley et al., Human Anatomy, 4e.
Objectives:
• Histology: Identify structures indicated on three different
slides or images of nervous system tissue. Some of these are
also visible on the classroom model of a neuron.
• Human brain: Identify listed structures of the human brain on
classroom models, the cranial meninges, and structures
involved in cerebrospinal fluid circulation.
• Human brain: Identify the 12 pairs of cranial nerves by name
and number on a model and on the sheep brain.
• Dissect a sheep brain and identify structures listed.
1Compilation: Mohammad Tomaraei & Cristin Fail

2. Nervous System Tissues: Spinal Cord Smear (Histology)
2

3. Nervous System Tissues: Cross Section of a Nerve (Illustration)
3

4. Nervous System Tissues: Cross Section of a Nerve (Histology)
4

5. Nervous System Tissues: Cross Section of a Nerve (Histology)
5

6. Nervous System Tissues: Teased Myelinated Nerve Fibers (Histology)
6

7. Nervous System Tissues: Multipolar Neuron Model
7

8. Nervous System Tissues: Multipolar Neuron Illustration
8

9. Brain Anatomy – Adult Human Brain
9

10. Brain Anatomy – Sheep Brain
10

11. Brain Anatomy – Adult Human Brain
11

12. Brain Anatomy – Sheep Brain
12

13. Brain Anatomy – Sheep Brain
13

14. Brain Anatomy – Cerebrum
14

15. Brain Anatomy – Cerebrum
15
• Cerebral hemispheres are divided by the longitudinal fissure into left
and right sides
• Central sulcus divides the frontal lobe from parietal lobes

16. Brain Anatomy – Lobes of the Brain
16

17. Brain Anatomy – White Matter of Cerebrum
17

18. Brain Anatomy – Cerebral Hemispheres
18

19. Brain Anatomy – Hemispheric Lateralization
19

20. Brain Anatomy – Lobes of the Brain
20

21. Brain Anatomy – Lobes of the Brain & their Functions
21
Frontal Lobe Parietal Lobe
Occipital
Lobe
Temporal
Lobe
Brain
Stem
Cerebellum
• Primary Motor
Cortex
(Precentral
Gyrus)
• Voluntary motor
functions
• Concentration
• Verbal
communication
• Decision making
• Planning
• Personality
• Primary
Somatosensory
Cortex
(Postcentral
Gyrus)
• Sensory
functions (Pain,
heat and other
sensations)
• Comprehension
of language
• Primary
Visual
Cortex
• Processing
visual
information
• Storing
visual
memories
• Understanding
Speech
• Interpretation
and storage of
auditory and
olfactory
sensations
• Breathing
• Swallowing
• Heart rate
Includes
Midbrain,
Pons, and
Medulla
Oblongata
• Coordination
• Balance
• Stores
memories of
previously
learned
movement
patterns

22. Brain Anatomy – Primary Somatosensory Cortex
22
The amount of cortex devoted to any given body region is
proportional to how richly innervated that region is.

23. Brain Anatomy – Homunculus Model
23
Which model is more realistic?

24. Brain Anatomy – Cross-section Brain Model
24
1. Corpus Callosum
2. Corpora Quadrigemina
(Tectal Plate)
• Superior Colliculus (pl.
colliculi)
• Inferior Colliculus
3. Cerebellum (Arbor Vitae)
4. 4th Ventricle
5. Central canal of spinal cord
6. Medulla Oblongata
7. Pons
8. Pituitary gland
9. Optic Chiasm
10. Hypothalamus
11. Thalamus
12. Septum Pellucidum
13. Fornix
14. Pineal Gland

25. Brain Anatomy – Corpus Callosum
25
• Carries messages between the
left and right hemispheres
• Its under surface forms the roof of
the body of the lateral ventricle.

26. Brain Anatomy - Diencephalon
• Sits on top of the brain stem
• Enclosed by the cerebral
hemispheres
• Made of three parts
• Thalamus
• Hypothalamus
• Epithalamus
26

27. Brain Anatomy - Diencephalon
27

28. Brain Anatomy – Epithalamus & Pineal Gland
• Pineal gland is an
endocrine gland that
secretes the hormone
Melatonin.
• Melatonin helps
regulate day-night
cycles known as the
body’s Circadian
Rhythm.
28

29. Brain Anatomy – Thalamus & the Interthalamic Adhesion
• The Interthalamic
Adhesion is
located midsagitally
and connects the
left and right
thalamic bodies
29

30. Brain Anatomy – Hypothalamus
30
Includes:
• Mammillary
Body
• Infundibulum
• Pituitary Gland
• Optic Chiasm
• Optic Tracts
• 3rd Ventricle

31. Brain Anatomy – Functions of Hypothalamus
31
• Master control of the autonomic nervous system
• Heart rate, blood pressure, digestive activities and respiration
• Master control of the endocrine system
• Metabolism, growth, stress responses and reproduction
• Regulation of body temperature
• Body’s “thermostat”, detects altered blood temperatures, heat or cool
the body: shivering/sweating
• Control of emotional behavior
• Emotional responses: pleasure, aggression, fear, rage, contentment
and sex drive
• Control of food intake
• Monitors levels of glucose and amino acids in the blood and
produces sensations of hunger
• Control of water intake
• Monitors blood solute concentration
• Regulation of sleep-wake rhythms
• The Suprachiasmatic Nucleus directs the Pineal gland to secrete
melatonin, regulating circadian rhythms.

32. Brain Anatomy – Brain Stem
32
Includes:
• Midbrain
(mesencephalon)
• Pons
• Medulla Oblongata

33. Brain Anatomy – Overview of Brain Stem Functions
33

34. Brain Anatomy – Midbrain
34
Includes:
• Corpora Quadrigemina
(tectal plate)
• Superior Colliculus:
Visual reflex center
(turns eyes and head
in response to visual
stimulus)
• Inferior Colliculus:
Auditory reflex center
(turns eyes and head
in the direction of a
sound)
• Cerebral Peduncles

35. Brain Anatomy – Pons
35
Functions:
• Bridge between the
cerebellum and
cerebrum
• Houses cranial nerves
• Trigeminal (CN V)
• Abducens (CN VI)
• Facial (CN VII)
• Some of the nuclei for
Vestibulocochlear (CN
VIII)
• Helps regulate skeletal
muscles of breathing

36. Brain Anatomy – Medulla Oblongata
36
Functions:
• Regulates heart rate
and strength of
contraction
• Controls blood pressure
• Regulates respiratory
rate
• Involved in coughing,
sneezing, salivating,
swallowing, gagging
and vomiting

37. Brain Anatomy – Medulla Oblongata & Pons
37

38. Brain Anatomy – Medulla Oblongata & Pons
38

39. Brain Anatomy – Cerebellum
39
Functions:
• Processes sensory input
• Coordinates movement
output
• Balance
Includes:
• Vermis
• Separates right and left
hemispheres
• Arbor Vitae (“tree of life”)

40. Brain Anatomy – Cerebellum
40

41. Brain Anatomy – Cerebellum
41

42. Brain Anatomy – Meninges and Spaces
42

43. Brain Anatomy – Cranial Dural Septa
43

44. Brain Anatomy – Dural Venous Sinuses
44

45. Brain Anatomy – Ventricles
45

46. Brain Anatomy – Ventricles
46

47. Brain Anatomy – Circulation of Cerebrospinal Fluid
47

48. Brain Anatomy – Cranial Nerves
48
1. Olfactory nerve (I)
2. Optic nerve (II)
3. Oculomotor nerve (III)
4. Trochlear nerve (IV)
5. Trigeminal nerve (V)
6. Abducens nerve (VI)
7. Facial nerve (VII)
8. Vestibulocochlear nerve
(VIII)
9. Glossopharyngeal nerve
(IX)
10. Vagus Nerve (X)
11. Accessory Nerve (XI)
12. Hypoglossal nerve (XII)

49. Brain Anatomy – Cranial Nerves
49

50. Brain Anatomy – Cranial Nerves
50
Sensory, Motor or Both
1. Some
2. Say
3. Marry
4. Money
5. But
6. My
7. Brother
8. Says
9. Big
10.Brains
11.Matter
12.Most

51. Brain Anatomy – Origins of Cranial Nerves
51

52. Brain Anatomy – Sheep Brain
52

53. Brain Anatomy – Sheep Brain
53

54. Brain Anatomy – Trigeminal Nerve
54

55. Brain Anatomy – Facial Nerve
55

56. Brain Anatomy – Vestibulocochlear Nerve
56

57. Brain Anatomy – Glossopharyngeal Nerve
57

58. Brain Anatomy – Vagus Nerve
58

59. Brain Anatomy – Accessory & Hypoglossal Nerve
59

60. Brain Anatomy – Cerebral Nuclei
60
Includes:
• Caudate Nucleus
• Lentiform Nucleus
• Putamen
• Globus Pallidus
• Claustrum
• Amygdaloid body

61. Brain Anatomy – Cerebral Nuclei
61

62. Brain Anatomy – Functions of Cerebral Nuclei
62
• Caudate
• Spatial processing
• Posture and directed movements
• Putamen
• Controls muscular movements at the subconscious level
• Globus Pallidus
• Excites and inhibits the activities of the thalamus to control muscle tone
• Amygdaloid body
• Expression of emotions , control of behavioral activities, development of
moods
• Claustrum
• Processes visual information at a subconscious level

63. Brain Anatomy – Lobes & Structures of the Brain
63
B.
A.
C.
D.
E.
F.
G.
http://williamcalvin.com/BrainForAllSeasons/img/bonoboLH-humanLH-viaTWD.gif

64. Brain Anatomy – Lobes & Structures of the Brain
64
B.
A. (groove)
C. (groove)
D.
E.
F.
G.
B. Frontal Lobe
G. Parietal Lobe
F. Occipital Lobe
D. Temporal Lobe
A. Central Sulcus
(groove)
E. Transverse Fissure
C. Lateral Fissure
http://williamcalvin.com/BrainForAllSeasons/img/bonoboLH-humanLH-viaTWD.gif