Neuroscience Intro

Question 1

The anatomical orientation for the human brain comes from what position?

Answer 1

Quadrupedal position (Doggy Position)

Question 2

Name and define Forebrain (Cerebrum) orientation directions.

Answer 2

Rostral–Toward the frontal bone.
Caudal–Toward the occipital bone.
Dorsal–Toward the top of the skull. (Think of doggy position with person looking forward.)
Ventral–Toward the inferior part of the skull. (Think of doggy position with person looking forward. This makes the brainstem closer to the front of the body.)

Question 3

How is the direction of orientation for the brainstem and its appendages different from the forebrain?
What is the name of this orientation?

Answer 3

The orientation of the brainstem is angulated at 80 degrees compared to the forebrain, in cephalic flexure.
The directions also change (think of where the dog’s tail is)
Rostral and Caudal are superior/inferior (toward head/toward tail)
Dorsal and Ventral are back to front.

Question 4

What are the 3 parts of the Brainstem?

Answer 4

Midbrain
Pons
Medulla

Question 5

What are the 4 directions that never change? What are they based on?

Answer 5

Superior
Inferior
Anterior
Posterior

Vertical anatomic position.

Question 6

What are the 5 subdivisions and the anatomy of the adult brain?

Answer 6

1. Telencephalon–“end-brain” Temporal lobes.
2. Diencephalon–“In-between-brain” Deep in brain but above the brainstem.
3. Mesencephalon–“Mid-brain” Top part of Brainstem (S–comes first)
4. Metencephalon–“Anterior hind-brain” Pons and Cerebellum
5. Myelencephalon–“Posterior hind-brain” Medulla

Question 7

The 5 subdivisions of the adult brain can be further compartmentalized into 3 subdivisions.
What are the subdivisions of the 5 subdivisions, and how are the 5 subdivisions distributed through the 3 subdivisions?

Answer 7

1. Forebrain: (not to be confused with forehead)…Telencephalon–end-brain and Diencephalon–in-between-brain.
2. Midbrain: Mesencephalon–mid-brain
3. Hindbrain: Metencephalon–anterior hind-brain and Myelencephalon–posterior hind-brain.

Question 8

The Telencephalon forms what 4 structures in each hemisphere of the cerebrum?

Answer 8

It is an embryological structure that forms:
Cerebral hemispheres
Caudate
Putamen
Globus pallidus
(all 3 together are known as the basal ganglia)

Question 9

What are the 4 lobes of the Cerebrum?

Answer 9

Frontal lobe
Parietal lobe
Temporal lobe
Occipital lobe

Question 10

What are the 5 structures of the Diencephalon?

Answer 10

Thalamus
Hypothalamus
Epithalamus
Prethalamus (subthalamus)
Pretectum

Question 11

Describe the Thalamus and Hypothalamus. In what region of the brain do they reside?

Answer 11

Thalamus–“ant-room” or “ room before” the cerebral cortex. Egg shaped. Decides where messages need to go. All cranial nerves (except olfactory) and all Sensory nerves have a synaptic connection in the Thalamus.

Hypothalamus–“below the thalamus.” Regulates homeostasis such as body temperature and endocrine function. Connected to pituitary gland. Sympathetic v Parasympathetic.

Question 12

Mesencephalon or Mid-brain is composed of what 2 parts?

What 2 structures is it between?

Answer 12

Tectum (Dorsal portion)
Tegmentum (Ventral portion)
Located rostral to the pons and caudal to the Thalamus and the basal ganglia.

Question 13

What is the Mesencephalon’s chief function?

What are its 7 other functions?

Answer 13

Visual and Auditory reflex movement center. (Tectum).
Controls eye movement.
Pupillary dilation,
Auditory function,
Pain control centers,
Ascending reticular activating system,
Somatic ascending pathway (information on the way to the thalamus
Somatic descending pathway.

Question 14

What 2 anatomical features make up the Metencephalon?

What is the function of each?

Answer 14

Cerebellum–Coordinates, guides, and refines learned gross and fine motor skill movement and instructs the rest of the nervous system.
Pons–“Bridge” It is the bridge to the Cerebellum from the Cerebral Cortex. Somatic movement pathway inferiorly. Respiration.

Question 15

Where is the Myelencephalon located?
What is its main structure and its definition?
Why is it named this?

Answer 15

Inferior to the basal pons and ends at the decessation for the pyramids.
Medulla Oblongata: “Long white marrow structure”.
Early neuroanatomists thought this looked like a long white structure because of its myelinated “white” axons. (Projection pathway)

Question 16

What 3 regions make up the brain stem?

Answer 16

Mesencephalon
Metencephalon
Myelencephalon.

Question 17

Define CNS, PNS, and ANS

Answer 17

CNS: Central Nervous System–includes the brain and spinal cord.
PNS: Peripheral Nervous System–This resides or extends outside the central nervous system.
ANS: Autonomic Nervous System–This system includes the sympathetic and parasympathetic biasing system. (Runs to blood vessels and internal organs. Therefore, ANS is considered part of the PNS because it has neurons that lie outside the CNS.