1. Central Nervous System
Brain & Spinal Cord

2. Development of the CNS Appears as neural tube on dorsal median plane
4th week brain formation begins at anterior end of the neural tube
Remaining portion of neural tube becomes spinal cord

3. 4 Major Regions of the Brain
Cerebrum (Cerebral hemispheres)
Cerebellum
Brain Stem
Diencephalon

4. Cerebrum
Divided into left and right hemispheres (What do you already know about them?)
Surface is covered in elevated ridges and shallow grooves
Gyri- ridges
Sulci- grooves
Let’s think of a way to remember these!
Fissures are deep grooves that separate large regions of the brain

5. Cerebrum Gray matter: White matter:
Outermost portion of the cerebral cortex
Neuronal cell bodies are located here
White matter:
Inner tissue of cerebrum
Bundles of fiber tracts (neuronal axons!)
Basal nuclei- small islands of gray matter within inner cerebrum
Regulate voluntary motor activities

6. The Brain Matters 
Locate the gray matter, the white matter, and the basal nuclei.

7. Cerebrum separated into 4 lobes

8. Each lobe of the cerebrum is unique
Frontal Lobes
Parietal Lobes
Temporal Lobes
Occipital Lobe
Do these names sound familiar?

9. Corpus Callosum Large fiber tract
Connects and allows communication between left & right hemisphere
“Split-Brain” patients
Severed corpus callosum

10. Split-Brain Patients
Article:

11. Brain Stem Parts of the Brain Stem:
Midbrain
Pons
Medulla oblongata
Provides a pathway for ascending & descending tracts from the brain to the spinal cord
Reticular Formation
Gray matter extending along brain stem involved in motor control of organs & consciousness

12. Brain Stem

13. Diencephalon
Located on top of the brainstem surrounded by the cerebral hemispheres
Many structures in the diencephalon
Thalamus
Hypothalamus
Pituitary
Pineal Body
Choroid Plexus
Amygdala
Hippocampus

14. Cerebellum Located under the occipital lobe of the cerebrum
It has two hemispheres with an outer cortex of gray matter and inner region of white matter

15. “Let Me Pick Your Brain” Activity
Awesome 3D Brain Website:
G2conline.com
Pages in your book

16. CNS Protection Bones of the skull and vertebral column
Connective tissue membranes called Meninges
Aqueous cushion called the cerebrospinal fluid (CSF)
Blood-brain barrier made by the least permeable capillaries in the body keeps the brain in a constant environment
What would happen if the brain were exposed to various ions?

17. Meninges of the Brain Dura Mater Arachnoid Mater Pia Mater
Outermost thick, tough, double layered membrane
Arachnoid Mater
Middle layer with many projections that has CSF flowing through it
Arachnoid villi protrude through dura mater, allowing CSF to drain into superior sagittal sinus to the blood
Pia Mater
Delicate innermost vascular layer that follows every convolution of the brain and spinal cord

18. Cerebrospinal Fluid We know where it drains… but where is it made?
Made in the choroid plexuses on roof of ventricles in the brain
The choroid plexuses make about mL of CSF per hour
The body has about 150 mL of CSF at a time
Circulates throughout the CNS
Which cells help circulate CSF?

19. Blood-Brain Barrier
Brain is the only body organ that cannot handle any environmental fluctuations
Neurons are sequestered from substances in the blood by nearly impermeable capillaries

20. Spinal Cord Continuation of the brain stem 3 layers of Meninges
31 pairs of spinal nerves
Gray matter is on the inside & contains neuron cell bodies
White matter is on the outside & contains axons