Neuroanatomy 1

What does the Central nervous system (CNS) consist of

Central Nervous System (CNS)

• Brain

• Spinal cord

What does the Peripheral nervous system consist of

• Everything else

• Nerves

• Motor Pathways

• Sensory pathways

What does the brain consist of?

• Cerebellum

• Cerebrum

• Brain stem

Recieves a constant flow of blood from heart (approx 20%)

The two hemispheres

Left and right

Contralateral = opposite side

Ispilateral = same side

Anatomical directions

Planes and sections

Frontal (coronal) - Parallel to forhead

Saggital - arrow

Horizontal- Parallel to ground

What does grey matter consist of?

• Cell bodies and dendrites

• E.g. cortex, basal ganglia, thalamus

What does white matter consist of

• Myelinated axons

• E.g. the corpus callosum

• A pathway that connect left and right side of hemisphere is called a commissure.

What is the corpus callosum?

“Hard body”

The largest fiber bundle that connects the two hemispheres of the brain

How does Meninges protect the nervous system?

3 layers of tissue that protect the brain and spinal cord (CNS)

How does Cerebrosphinal fluid (CSF) protect the nervous system

• A clear fluid that fill the subarachnoid space

• Functions: shock absorber, buoyancy

What are the ventricles

• Hollow cavities filled with CSF

• Lateral ventricles x2

• Membraine called choroid plexus produces CSF by filtering blood

• Third ventricle

• Cerebral aqueduct

• Fourth ventricle

• Functions continued: exchange of materials between blood vessels and brain tissue

What is the blood brain barrier

• A semipermeable barrier

• Lipid soluble substances can pass through. Substances with large molecules (e.g., glucose) must be actively transported through walls.

Purpose of the blood brain barrier

• Maintain stable environment

• Protection from potentially disruptive/damaging chemicals

What is the cerebral cortex

• Outer surface cerebrum

• 3mm thich

• Folded to allow a bigger surface area

• Clefts/cracks/grooves = sulci

• Major grooves = fissures

• Folds/bulges = gyri

Lobes of the cerebral cortex

• Frontal

• Parietal

• Occipital

• Temporal

Major sulci and Gyri

• Central sulcus

• Precentral gyrus

• Postcentral gyrus

• Sylvian

• Fissure / lateral

• Fissure

What is the frontal lobe

• The anterior area of the cortex, rostral to parietal lobe, dorsal to temporal lobe

• Divided from parietal lobe by the central sulcus

• Functions: motor and cognition

What is the parietal lobe

• Caudal to frontal lobe, dorsal to temporal lobe

• Function- somatosensory

What is the occipital lobe

• Caudal to parietal and temporal lobes

• Function: vision

What is the temporal lobe

• Rostral to occipital lobe and ventral to parietal and frontal lobes

• Functions: hearing, vision, cognition, emotion

Primary areas

• Primary somatosensory cortex

• Primary visual cortex

• Primary auditory cortex

• Primary motor cortex- connected to muscles in body

All contralateral (except olfaction and taste)

Primary association areas

Sensory association areas- receive and analyse info from primary regions