Lecture 3.2: Brain and Cranial Nerves

What are the cranial meninges? (deepest to most superficial)

Pia mater, arachnoid mater, dura mater

Name the meninge

Dura mater

Name the meninge

Arachnoid mater

Name the meninge

Pia mater

What are the dural venous sinuses?

Meningeal layer, periosteal layer

Name the dural mater layer

Periosteal layer

Name the dural mater layer

Meningeal layer

Name the structure

Dural venous sinus

Name the structure

Skin

Name the structure

Arachnoid

Name the structure

Pia

What structures are included in the dural septa?

Falx cerebri, tentorium cerebelli

Name the structure

Falx cerebri

Name the structure

Tentorium cerebelli

Name the structure

Falx cerebri

Name the structure

Tentorium cerebelli

Name the structure

Transverse sinus

Name the structure

Confluence

Name the structure

Superior sagittal sinus

Name the structure

Inferior sagittal sinus

Name the structure

Straight sinus

Name the structure

Confluence

Name the structure

Transverse sinus

Name the structure

Sigmoid sinus

Name the structure

Lateral ventricles (x2)

Name the structure

3rd ventricle

Name the structure

Cerebral aquaduct

Name the structure

4th ventricle

Name the structure

Lateral ventricles (x2)

Name the structure

3rd ventricle

Name the structure

Cerebral aquaduct

Name the structure

4th ventricle

Define cerebrospinal fluid

A clear liquid that circulates in the ventricles and subarachnoid space

What are the functions of cerebrospinal fluid?

Buoyancy, protection, chemical stability

How is CSF formed?

By the choroid plexuses (ependymal cells + capillaries) within each ventricle

Describe CSF circulation

1. CSF is produced by the choroid plexus in the ventricles

2. CSF flows from 3rd ventricle to the cerebral aquaduct to the 4th ventricle

3. CSF flows from 4th ventricle to the subarachnoid space to the central canal of spinal cord

4. Excess CSF flows into arachnoid granulations (villi), which drain into the dural venous sinuses

What structures are included in the telecephalon brain region?

Cerebrum

What structures are included in the diecephalon brain region?

Epithalamus, thalamus, hypothalamus

What structures are included in the mesencephalon brain region?

Midbrain

What structures are included in the metencephalon brain region?

Pons, cerebellum

What structures are included in the myelencephalon region?

Medulla oblongata

What brain structures are a part of the brain stem?

Midbrain, pons, medulla oblongata

Name the brain structure

Cerebrum

Name the brain structure

Epithalamus, thalamus, hypothalamus

Name the brain structure

Midbrain

Name the brain structure

Pons

Name the brain structure

Medulla oblongata

Name the brain structure

Cerebellum

How is the brain organized?

Grey matter and white matter

Describe grey matter

Contains motor neuron and interneuron cell bodies

How is grey matter distributed?

Cerebral cortex, nuclei

Describe white matter

Contains axons

Describe the distribution of white matter

Internal surfaces of the brain

Describe the type of matter

White matter

Describe the type of matter

Grey matter

Name the structure

Nuclei

Name the lobe

Frontal

Name the lobe

Parietal

Name the lobe

Temporal

Name the lobe

Occipital

Name the structure

Cerebrum

Name the structure

Cerebellum

Name the structure

Brain stem

Name the structure

Cerebral hemisphere

Name the structure

Longitudinal fissure

Name the lobe

Frontal

Name the lobe

Parietal

Name the lobe

Occipital

Name the structure

Longitudinal fissure

Name the structure

Corpus callosum

Name the lobe

Insula

Define sulci

Grooves or fissures

Define gyri

Ridges, raised areas

Name the structure

Sulci

Name the structure

Gyri

Name the structure

Precentral gyrus

Name the structure

Central gyrus

Name the structure

Post-central gyrus

What are the functional areas of the cerebrum (LOBES)?

Frontal lobe, insula, parietal lobe, temporal lobe, occipital lobe

What are the primary structures included in the frontal lobe?

Primary motor cortex, premotor cortex, frontal eye field, motor speech area

What are the primary structures included in the insula?

Primary gustatory cortex

What are the primary structures included in the parietal lobe?

Primary somatosensory cortex, somatosensory association area

What are the primary structures included in the occipital lobe?

Primary visual cortex, visual association area

What are the primary structures included in the temporal lobe?

Primary auditory cortex, auditory association area, primary olfactory area

What are the functional areas of the cerebrum (CORTEXES)?

Primary (SOMATIC) MOTOR cortex, Primary SOMATOSENSORY cortex

Where is the primary (somatic) motor cortex located?

Within precentral gyrus

Where is the primary somatosensory cortex located?

Within postcentral gyrus

Contrast the precentral gyrus with the postcentral gyrus

Precentral gyrus controls voluntary movement and motor function, postcentral gyrus controls sensory perception

Describe cerebral (basal) nuclei of the cerebrum

Gray matter within inner white matter (composed of interneuron and motor neuron cell bodies)

Name the structure

Cerebral (basal) nuclei

Name the structure

Cerebral (basal) nuclei

Describe white matter tracts of the cerebrum

Bundles of axons that create pathways for neural signals and thus connect parts of the CNS

Describe association tracks of the cerebrum

Connect areas within the same hemisphere

What are the types of association tracks?

Arcuate fibers, longitudinal fasciculi, commissural tracts, projection tracts

Describe the function of arcuate fibers

Connect gyri WITHIN a lobe

Describe the function of longitudinal fasciculi

Connect gyri BETWEEN lobes

Describe the function of commissural tracts

Connect corresponding lobes BETWEEN hemispheres

Describe the function of projection tracts

Connect the cerebral cortex to other parts of the CNS

What do commissural tracts cross?

Corpus callosum

Name the structure

Arcuate fibers