1. This Is Your Brain Intro to Psych Class #2 1/30/14

2. The Nervous System • Central Nervous System • Brain & Spinal Cord • Peripheral Nervous System • All other nerves in the body • All branch off from the spinal cord Intro to Psych Class #2 1/30/14

3. The Nervous System What does it DO? It controls EVERYTHING! Intro to Psych Class #2 1/30/14

4. The Nervous System How does the message “take a step” get from your brain to your foot? NEURONS! Intro to Psych Class #2 1/30/14

5. Neurons • Your brain has about 1,000,000,000,000 neurons • Different types of neurons: • Sensory neurons: “That’s hot!” • Motor neurons: “Take a step” • Interneurons: connect one neuron to another • Intensity: demonstrated by number of neurons firing & how fast/slow they’re firing Intro to Psych Class #2 1/30/14

6. Neurons • Cell Body – Main part of the neuron (may also be called soma) • Dendrites – collect the signals from other neurons • Axon – transmits the signal to other neurons • Myelin Sheath – fatty cells wrapped around the axon • Axon Ending – Very end of the axon; electrical signal converts to chemical message and passes on to next neuron Intro to Psych Class #2 1/30/14

7. Neurons • Synapses – gap between the axon end of one neuron and the dendrite of the next neuron; messages pass through here • Neurotransmitter – chemical message released across the synaptic gap to connect to the next neuron Intro to Psych Class #2 1/30/14

8. Neurotransmitters • What makes someone feel “drunk”? • What makes someone feel “high”? NEUROTRANSMITTERS Drugs and alcohol affect the process of neurotransmission and cause the chemicals of the brain to react differently than normal, causing someone to feel “high” or “drunk” or also to fall down, fall asleep, slur their words, etc Intro to Psych Class #2 1/30/14

9. Your Brain Intro to Psych Class #2 1/30/14

10. Phineas Gage & the metal rod • 25 year old railroad worker • Clearing boulders by packing gunpowder using a large metal rod • A spark ignited the gunpowder, causing the metal rod to shoot up into Gage’s left cheek, go through his forebrain, and come out the top of his skull Intro to Psych Class #2 1/30/14

11. Phineas Gage & the metal rod Intro to Psych Class #2 1/30/14

12. Phineas Gage & the metal rod • Gage survived another 12 years, but was a different man after the accident • Before: friendly, popular, hardworking • After: ornery, irresponsible, disliked, a bully But why did he change??????? Physical brain damage or psychological damage? Intro to Psych Class #2 1/30/14

13. Your Brain Intro to Psych Class #2 1/30/14

14. Your Brain Intro to Psych Class #2 1/30/14

15. Lefties vs Righties! • How left or right handed are you? • Which hand do you normally use to write with? • Which hand would you use to throw a ball at a target? • Which hand do you use to hold your toothbrush? • Which hand do you use to hold a knife when cutting food? • With which hand do you hold a hammer when hitting a nail? • When you thread a needle, which hand holds the thread? About 77% of people are strongly right or left handed Intro to Psych Class #2 1/30/14

16. Lefties vs Righties! “Left handed people are in their right mind” Kinda… Right hemisphere does control the left hand, but the dominant hemisphere, the one that produces language, may be on the opposite side The trick is in the way you write… Intro to Psych Class #2 1/30/14

17. Lefties vs Righties! Lefties who write with a hooked hand & righties who write straight are usually left-brain dominant Righties who write with a hooked hand and lefties who write straight (like me!) are usually right-brained dominant Intro to Psych Class #2 1/30/14