1. The Nervous System & its Cells

2. Central (inside skull & spine) Brain Spinal Cord Divisions of the Nervous System Peripheral (outside skull & spine) Nerves

3. Central Nervous System Brain

4. Divisions of the human brain

5. Specialization of function Different regions of the brain are associated with different function

6. Spinal Cord Reflex Spinal cord lesion Ouch! That hurts, dude! Group activity - Would sensation be abolished by: - a spinal cord lesion? - polio? - Would the reflex be abolished by: - a spinal cord lesion? - polio?

7. Somatic System : - controls voluntary muscle Autonomic System : - controls glands & internal organs - has two subcomponents - Sympathetic (adrenaline): arousal - Parasympathetic: calm Peripheral Nervous System

8. Levels of Investigation Brain Areas (visual system) Cells (neurons) Molecules (neurotransmitters )

9. 9 Neurons: Its many shapes & sizes

10. Neuron: basic parts Cell Body football field Dendrite Campus Axon wide a street Axon long as Philly - Ohio Cell membrane thick as pinky finger Synaptic cleft thick as thumb # synapses 10.000 (same number as Villanova students) Some axons are wrapped burrito-style by fatty cells (glial cells) - increases speed at which neurons communicate) - white in color (white matter vs gray matter - is destroyed by multiple sclerosis axon terminals

11. 11 Neuron: its physiology What makes neurons different from other cells? Neuron’s cell membrane is electrically charged (interior is more negative) Neurons influence each other’s charge (‘communicate’) Neurons process and transmit electrical impulses

12. 12 How do neurons process and transmit electrical impulses? A. dendrites receive input from other neurons B. axon sends neural impulse to axon terminal C. a neurotransmitter (NT) is release and makes contact with another neuron (synapse)

13. Communication Steps NT is released from pre-synaptic neuron NT binds to receptors in post-synaptic neuron Opens Na+ channels Sodium rushes in (activation) If enough Na+ rushes in => depolarization (action potential) NT released by post- synaptic neuron Post-synaptic neuron Synapse Pre-synaptic neuron

14. Other important facts Various Neurotransmitters (NT): -Dopamine -Adrenaline -Serotonin -Acetylcholine For each NT,various receptors - nicotine & muscarine Drugs can act by - modifying amount of NT, or - binding to receptor (nicotine) The net effect on neuron could be: - activation (action potential) - inhibition