The Brain and Cranial Nerves

Name the 4 major parts of the brain

Name the 4 major parts of the brain

• Diencephalon

• Brain Stem

• Cerebrum

• Cerebellum

Name the 3 regions of the brain stem

• Midbrain

• Pons

• Medulla

• Oblongata

Name the 3 major regions of the diencephalon

• Thalamus

• Hypothalamus

• Pineal gland

Name the 4 lobes of the brain found in each cerebral hemisphere

• Frontal

• Parietal

• Temporal

• Occipital

Differentiate between grey, sulci, and fissures

Fissures form the deep furrows, while the sulci are the shallow ones. The ridge between the sulci are the gyri.

How does the location of the white and grey matter in the cerebrum, differ from that in the spinal cord

• White matter sits externally to the grey matter in the spinal cord.

• The cerebrum, grey matter is external and white matter is internal

What is Cerebrum

The largest and most superior part of the brain, divides into the convoluted cerebral hemispheres by a deep longitudinal fissures

What is Diencephalon

Between the midbrain and the corpus callosum, composed of the thalamus, epithalamus, and the hypothalamus

What is the Brainstem

The stalk-like lower portion of the brain, composed of all the brain except the cerebrum, cerebellum, and diencephalon

What is the Cerebellum

A large portion of the brain that's posterior to the brainstem and inferior to the cerebrum, responsible for equilibrium, motor coordination and memory of learned motor skill

Where is white matter located

inner core

Where is grey matter located

outer area / cortex surrounding the white matter in the cerebrum, cerebellum, and nuclei

Nuclei

Clusters of neuron cell bodies found only in the CNS

Ganglia

Found in PNS

Tracts

• Collection of axons

• Tracts are found within the CNS

Nerves

• Collection of axons

• Nerves are found in the PNS

Dura Matter

• "Tough mother"

• Outermost layer, strongest of the 3 meninges

• Pain sensitive

• Double layered membrane

Arachnoid Matter

• Web like and avascular

• Loose brain covering

• Separated from the dura by the subdural space

• Separated from the Pia by the subarachnoid space

• Subarachnoid space contains the CSF and the blood vessels

Pia Matter

• "Gentle mother"

• Thin and highly vascular

• Clings tightly to the brain and follows ever

Define the ventricles of the brain

The ventricles of the brain contains CFS

Production

The choroid plexuses and the cell lining the ventricles

Circulation

Subarachnoid space

what are the 3 functions

• Mechanical protection

• Chemical protections

• Circulations

Mechanical protection

Floats brain and softens impact with bony walls

Chemical protections

Optimal ionic concentrations for action potentials

Circulations

Nutrients and waste products to and from bloodstream

State the significance of the blood-brain- barrier

• Protects the cell from some toxins and pathogens

• Maintain stable environment for the brain

• Tight junctions seal the cells of the capillaries ( supported by astrocytes)

Describe the concept of the brain lateralization

• Is the different functions of the left and right hemisphere of the brain

• Damage to 1 hemisphere or the other can produce different problems

State why the cerebral hemisphere control the opposite side of the body

• The 2 hemisphere of the brain control opposite sides due to crossing over the medulla

• When they cross the left nerves are now on the right side of the body and the right on the left

What is the cranial nerves by name and number

• 12 pairs

• Can be motor, sensory, or both

• Pass through the various foramina of the skull

Forebrain

CNI and II

Mid-brain

CNII and IV

Pons

CN V, VI, VII, VIII

Medulla

CN VII, IX X, XI, AND XII

Olfactory

• I

• Mostly sensory

Optic

• II

• Mostly sensory

Occulomotor

• III

• Mostly motor and parasympathetic fibres

Trochlear

• IV

• Mostly motor

Trigeminal

-V

• Mostly sensory and motor

Abducens

• VI -Mostly motor

Facial

• VII

• Sensory, motor, and parasympathetic fibres

Vestibulocochlear

• VIII

• Mostly sensory

Glossopharyngeal

• IX

• Sensory, motor, and parasympathetic fibres

Vegus

• X

• Sensory, motor, and parasympathetic fibres

Accessory

• XI -Mostly motor

Hypoglossal

• XII

• Mostly motor

How do the parts of the brain develop

The parts of the brain develop from secondary vesicles

Describe the effects of aging on the nervous system

• Loss of neutrons

• Diminished capacity for sending nerve impulses to and from the brain

• Diminished ability to process information

• Decreased conduction velocity -Slowing of voluntary motor movements

• Increased relax time

• Degenerative changes in visions, hearing, sight, taste, smell, touch , and balance

What are the parts of the brain

• Cerebrum

• Thalamus

• Pineal Gland

• Hypothalamus -Midbrain

• Pons -Medulla Oblongata -Cerebellum

• Pituitary Gland