3. Review

4. Central Nervous System
the CNS consists of the brain and spinal cord
is protected by
bone (skull and spinal column)
3 tough membranes called the meninges
cerebrospinal fluid (CSF) fills the space between the inner and middle membrane and cushions both the brain and spinal cord

5. Protected by bone:

6. Protected by meninges and cerebrospinal fluid:

7. Gray Matter vs. White Matter
Gray matter consists mainly of densely packed neuronal cell bodies and their dendrites.
White matter consists of bundles or tracts of myelinated axons. (white colour)

8. Brain Spinal Cord

9. The Spinal Cord
extends from the opening at the base of the skull, through the vertebral canal, to the lower back
conducts messages between the brain and peripheral nerves (sensory and motor)
controls reflex actions that do not require supervision by higher centers in the brain (the reflex arc)

10. Spinal Cord

11. Anatomy of the Brain Brain develops from the bottom up
the hindbrain consists of
Medulla
Pons
Cerebellum

12. Hindbrain

13. Hindbrain
Medulla: controls several automatic functions such as breathing, heart rate, blood pressure, and swallowing.
Pons: directs traffic, some neurons help control sleep/wake patterns
Cerebellum: balance and coordination, eg. Dance routine or writing

14. Midbrain: Coordinates reflex responses to sight and sound (eye and ear reflexes)

15. Forebrain the forebrain consists of the Thalamus Hypothalamus
Cerebral Cortex (Cerebrum)

16. Forebrain

17. Forebrain
Hypothalamus: regulates homeostatic functions: temperature control, thirst, urine output, and hunger.
Important link between nervous and endocrine system. It is connected to the pituitary gland: the master gland of the endocrine system.
Thalamus: relay station for all synaptic input (almost all sensory information enters this structure where neurons send that information to the overlying cortex).

18. Forebrain

19. Cerebral Cortex (Cerebrum)
controls higher processes and senses (speech, reasoning, memory, smell, touch, taste, hearing)
largest part of the human brain
divided into 2 hemispheres (right/left)
the two hemispheres do not function equally – one side may be more mathematical, the other may be artistic and musical
the left cerebral hemisphere controls the right side of the body, the right hemisphere controls the left side of the body

20. Cerebral Cortex a deep groove or fissure divides the 2 hemispheres
Corpus callosum: bundle of axons (approx. 300 million) which connect the two cerebral hemispheres.
Sometimes called the “Information superhighway”

21. Cerebral Cortex

22. The cerebral cortex is separated into 4 sections called “lobes”:
Occipital lobe: visual processing
Temporal lobe: sound sensation, memory, and speech
Parietal lobes: receiving and processing sensory input
Frontal lobes:
voluntary motor activity
speaking ability
elaboration of thought

25. Phineas Gage ( )