This is my favorite lab!

Gross Anatomy of the Brain & Cranial Nerves

Page 200 in the lab book

Terminology

Dorsal View = view from above

Ventral View = view from below

Transverse = split into top & Section bottom sides

Sagittal = split into left &Section right sides

CNS BrainSpinal Chord

PNS Cranial nerves Spinal Nerves Sensory Receptors

What physical characteristics of the human brain can you see in this picture?

1. Left and Right Half

2. Series of Ridges

RightHemisphere

LeftHemisphere

Longitudinal Fissure

Corpus Callosum

The Corpus Callosum connects the left and right hemispheres of the brain

Grass on the Gyrus ridge

Stream in the Sulcus valley

Brain Lobe FunctionFrontal Control of skeletal muscles

(Primary Motor Cortex)

Temporal Smell and hearing(Auditory/Olfactory Cortex)

Parietal Taste, pain, touch(Primary Sensory Cortex)

Occipital Vision(Visual Cortex)

The Ventricles of the Brain

Open Chambers within the brain filled with cerebrospinal fluid

Help cushion the brain

Prevent brain from crushing itself under its own weight

The Ventricles of the Brain

Lateral Ventricle

Third Ventricle

Cerebral Aqueduct

Fourth Ventricle

Dura Mater

Pia Mater

Meninges Around the Brain

The Meninges

Outer dura mater attaches to the inner surface of the skull and outer edge of the spinal cord

Inner pia mater attaches to the brain & spinal cord

The meninges help protect the brain & spinal cord

Provide space for a layer of cerebrospinal fluid around the brain and spinal cord

Cerebrospinal Fluid

Forms a watery cushion around and within the brain and spinal cord

Helps protect and support the brain

Continuously formed by a capillary knot in the brain called the Choroid Plexus

Eventually it drains back into the bloodstream

Meningitis

-itis means “inflamation”

Inflamation of the meninges caused by a viral or bacterial infection

Diagnosed by a spinal tap of the cerebrospinal fluid

Infection can spread to the brain, causing encephalitis

Meningitis

Hydrocephalus

Means “Water on the Brain”

Occurs in roughly 3 out of every 1000 newborns

Cerebrospinal fluid drainage is blocked

Cerebrospinal fluid builds up in the ventricles of the brain, putting pressure on the brain tissue

Hydrocephalus

What is the Gray Matter & White Matter?

Areas of the brain and spinal cord that differ in color

Color change caused by the nerve structures in that region of the Central Nervous System

Nerve Cell BodiesInformation Processsing

Myelinated AxonsInformation Transmission

The Cranial Nerves

12 Pairs of nerves that arise from the brain

Serve many functions in the head and neck region

Learn a function for each of the cranial nerves

The Cranial Nerves

The Cranial Nerves

Olfactory Nerve Sense of smell (Olfaction)

Optic Nerve Sense of vision

Oculomotor Nerve Eye movement

Trochlear Nerve Eye movement

Trigeminal Nerve Sense of touch on the face, mouth, and nose

The Cranial Nerves

Abducens Nerve Eye movement

Facial Nerve Facial expression Tear and Saliva excretion

Vestibulocochlear Hearing and balance

Glossopharyngeal Sensation in back of throat (pharynx)

The Cranial Nerves

Vagus Nerve Slows the heart rate Contraction of smooth muscle

in digestive organs

Accessory Nerve Controls swallowing Movement of trapezius

Hypoglossal Nerve Controls tongue movement

Now Let’s Look at Brains !!!