Neuroanatomy

Cerebral Spinal Fluid and Associated Organs

Q: What are the four ventricles responsible for circulating cerebral spinal fluid (CSF) around the brain?

A: Left + Right Lateral Ventricles, Third Ventricle (connect the lateral ventricles and the cerebral aqueduct), Fourth Ventricle (connects to the cerebral aqueduct and sends CSF to the subarachnoid layer of the meninges)

 

Q: Where is CSF created?

A: By cells called the choroid plexus in the fourth ventricle

 

Q: What are the meninges and what layers is it made of?

A: The meninges are thin membranes that surround the central nervous system and are made up of the Dura Mater (Tough Mother), Arachnoid Mater (Spider Mother), Subarachnoid Layer, Pia Mater (Little Mother) (Moving from the inside to outside).

 

Q: What functions do the Ventricles and Meninges serve in the Central Nervous System (CNS)?

A: It cushions the brain from injury by dispersing the impact, it provides buoyancy to the brain so that it doesn’t get crushed under its own weight, and it allows the circulation of CSF which provides nutrition to the brain

Blood Brain Barrier

Q: What molecules can pass through the Blood Brain Barrier (BBB) without the aid of Transport Proteins)?

A: Small, uncharged (Not ions), Lipophilic (Dissolves in lipids/fats) molecules like oxygen or carbon dioxide

 

Q: What major molecules can only pass the BBB with the aid of Active Transporter Proteins?

A: Mostly important nutrients like Glucose and Amino Acids

 

Q: What major molecules cannot pass through the BBB?

A: The pathogens and other larger hydrophilic (Dissolves in water) molecules

Peripheral Nervous System

Q: How many pairs of nerves does each of the following sections spinal cord have?

Section

Number of Pairs

Cranial

12

Cervical

8

Thoracic

12

Lumbar

5

Sacral

5

Coccygeal

1

 

Somatic Nervous System

Q: What is the Somatic Nervous System responsible for?

A: Communicating voluntary motor signals and sensory information to and from the CNS

 

Q: What routes (ventral vs. dorsal) send sensory information to the CNS?

A: Dorsal

 

Q: What routes (ventral vs. dorsal) send motor information from the CNS to the muscles?

A: Ventral

Autonomous Nervous System

Sympathetic Nervous System

Q: What is the function of the Sympathetic Nervous System

A: To prepare the body for vigorous activity by controlling the function of certain organs

 

Q: What section of the spinal cord do the nerves of the Sympathetic Nervous System extend from?

A: The Thoracic and Lumbar sections

 

Q: Does the Sympathetic Nervous System have long pre-ganglionic or post-ganglionic nerves?

A: Long post-ganglionic cells

Parasympathetic Nervous System

Q: What is the function of the Parasympathetic Nervous System?

A: Facilitate nonemergency responses such as digestion

 

Q: What section of the spinal cord do the nerves of the Parasympathetic Nervous System extend from?

A: Cranial and Sacral

 

Q: Does the Sympathetic Nervous System have long pre-ganglionic or post-ganglionic nerves?

A: Long pre-ganglionic nerves

Central Nervous System

Cerebral Cortex

Frontal Lobe

Q: What are the functions of each of the following regions of the Frontal Lobe

Region

Function

Primary Motor Cortex

Most important region of the brain responsible for movement

Premotor Cortex

Helps prepare for movement by integrating movement intentions with information about the body’s current position (p.g. 242 of textbook). Also, contains mirror neurons which makes it important for learning motor movements through imitation.

Supplementary Motor Cortex

Important for inhibiting habitual motor movements and planning of more complex movements

Prefrontal Cortex

Made of multiple cortices responsible for functions such as self-control, emotion regulation and language

Broca’s Area

Important for coordinating the motor responses necessary for communicating language (e.g. mouth movements in speaking or hand movement in writing)

 

Q: What word is used to describe the way that the Primary Motor and Primary Somatosensory Cortices are arranged and what does it mean?

A: Somatotopic, regions of the cortex that are adjacent usually correspond to regions of the body that are adjacent

Temporal Lobe

Q: What are the functions of the following regions of the Temporal Lobe?

Region

Function

Primary Auditory Cortex

Responsible for processing auditory stimulus

Medial Temporal Lobe

AKA The hippocampus (see below)

Wernicke’s Area

Responsible for functions related to language comprehension

 

Q: What word is used to describe the way that the Primary Auditory Cortex is arranged and what does it mean?

A: Tonotopic, regions of the cortex responsible for processing similar frequencies are usually adjacent.

Parietal Lobe

Q: What are the major functions of the Primary Somatosensory Cortex?

A: Integrating sensory information including pertaining to somatosensation and proprioception.

Occipital Lobe

Q: What is the major function of the Occipital Lobe?

A:  Processing of visual information

Limbic System

Q: What are the major functions of the following regions of the limbic system?

Region

Function

Amygdala

Processing of emotions (particular fear) and fear learning

Hippocampus

Responsible for the encoding of declarative memory

Cingulate Gyrus

Processing physical and emotional pain

Thalamus

Acts as a ‘relay station’ for sensory information before it is sent to the corresponding cortex for processing

Hypothalamus

Maintains homeostasis for the body by communicating with the Pituitary Gland

Basal Ganglia

Responsible for reward learning and habit formation

 

Basal Ganglia and Other Structures Important for Reward Learning

Q: What structures make up the Basal Ganglia?

A: Globus Pallidus and the Striatum (with is made of the Caudate Nucleus and the Putamen)

 

Q: In which structure of the Basal Ganglia will you find the Nucleus Accumbens?

A: The Putamen

 

Q: What are the two pathways between the striatum and thalamus, and what is the function of each?

A: The Direct pathway (Striatum -> Thalamus) is implicated in simple excitatory movement signals, while the Indirect pathway (Striatum -> Globus Pallidus -> Thalamus) is responsible for inhibiting maladaptive movements

 

Q: Which structure in the midbrain makes connections to the Basal ganglia that are important for reward learning?

A: The Ventral Tegmental Area

 

Q: What are the two dopaminergic pathways, what regions of the brain do they connect, and what are each of them responsible for?

Pathway

Regions

Function

Mesocorticolimbic

VTA -> Nucleus Accumbens

VTA -> Frontal Cortex

Reward Learning

Nigrostriatal

Substantia Nigra -> Striatum

Movement

 

Q: Identify the regions of the brain in the picture below

Region

Name

A

Frontal Cortex

B

Striatum

C

Substantia Nigra

D

Nucleus Accumbens

E

Ventral Tegmental Area

F

Hippocampus