B6 revision

1. B6 revision Brain and Mind An accelerated revision resource A.Blackford

2. WARNING This PowerPoint is not a substitute for active revision using notes, the workbook and revision guide. You also need to do plenty of past papers to get exam practice. Good luck! REVISION IS IMPORTANT

3. Behaviour • All living things respond to stimuli from the environment. • These responses are all examples of behaviour (e.g. eating, shivering, scratching, move out of the light) • These simple reflexes are important because they help animals • find food and shelter • Escape from predators • Avoid harmful environments

4. Simple Reflexes in Humans • These are often survival reflexes • The gag reflex when something touches the back of our throat • The pupil reflex in the eye to bright light • Newborn baby reflexes are an important indicator of good health • Step, gasp, startle, grasp, sucking, rooting and swimming • SIDS could possible happen because these simple reflexes have not matured

5. Brain Peripheral nerves Spinal cord The Nervous System • This is made up of the central nervous system (brain and spine) and the peripheral nervoussystem which links the CNS to the rest of the body. • The CNS coordinates the body responses

6. 2 RECEPTOR Pain receptors stimulated, sensory nerves take signals to CNS 1 STIMULUS Pin sticks into skin 3 CNS Coordinates the response. Sometimes the brain often the spinal cord for reflexes Sensory neurone 4 EFFECTOR Signals from the motor neurone makes the muscles contract Motor neurone Coordinating a Response

7. Neuron Structure • Nerves are bundles of many neurons (nerve cells) • Nerve impulses move from the cell along the axon of motor nerves • The myelin sheath is made up of ‘fatty cells’ that insulate the axon and help the signal to move faster down it. A motor nerve

8. Receptors and Effectors • Receptors monitor the external and internal environment • Receptors can be single cells (pain receptors in the skin) or grouped in a sense organ (eye, ear) • Effectors are either muscles (to contract) or glands (sweat, hormones, enzymes)

9. Conscious Control of Reflexes • Normally if we pick up a hot plate we would drop it straight away (reflex) • If it would be dangerous to do this our brain can override the reflex so that we put it down slowly • Not all reflexes can be overridden e.g. pupil response to bright light Note the connection to the brain to modify this reflex

10. 2 Chemical released from the nerve 1 Nerve impulse arrives down the axon of a sensory nerve 3 Chemical diffuses across the synapse (gap) 5 Transmitter chemical reabsorbed by the sensory nerve 4 A new nerve impulse is generated in the motor nerve Connecting Nerves • Nerve impulses can travel at 400m/s in the axon • The speed across the synapse is 15 m/s

11. Drugs and the Synapse Feel good chemical produced by the brain. Lack of it can cause depression Serotonin (natural) Antidepressant. Allow serotonin to build up in the brain by blocking its uptake at the synapse Prozac (medical) MDMA. Works in a similar way to prozac. May cause depression and anxiety and memory loss Ecstasy (illegal drug) Stops messages passing across the synapse. Paralysis and death! Curare(Medical/hunting)

12. The Brain All the ’LOBES’ are part of the cerebral hemisphere

13. Cerebral Hemispheres • This is a map of the part of the cerebral hemispheres that are to do with the senses • The proportion of the body parts gives some idea of the area of cortex given over to that part. • The cerebral cortex makes us what we are. Our ‘mind’ and consciousness is here. • Cerebral cortex in humans is thin but a large surface area (because it is folded)

14. Learned Behaviour This is ‘classic’ conditioning first done by Ivan Pavlov in 1904 .

15. Conditioning Aids Survival • Conditioned reflexes are usually examples of simple learning • Examples include birds avoiding brightly coloured (bitter) insects after trying one • Goldfish swimming to the surface for food when we go to the front of the bowl

16. Neuron 1 Neuron 2 Neuron 3 Human Learning • Learning takes place when new connections are made between neurones A Neurone 1 fires impulses close together. Link between 1 and 2 strengthened B Neurone 2 fires impulses more frequently. Link between 2 and 3 strengthened C Eventually there are strong links between all three neurones. A memory has been stored

17. Learning to Learn • Repetition helps build up the links between neurones (so PRACTICE and REVISE) • Visualising can help create links • Language is best learned before age 8 • Children who don’t learn any language when young may NEVER learn (as shown by FERAL children). These children may also have underdeveloped brains

18. Remember Me! 1 • Short term Memory • 30 seconds or so • 7 letters or numbers about the max • ‘Chunk’ information for easier recall later (divide lists into groups of 3) • Alzheimer’s disease causes short term memory loss • Sensory memory can store sound and visual information for a short time (e.g. sparkler writing)

19. Remember Me! 2 • Long term memory • Held in a different part of the brain to short term memory • Rehearsal, repetition or need will transfer information from short term to long term memory

20. Rehearsal (e.g. revision) Information not attended to is lost Information either passed on to long term memory or lost Multi-store Memory Model Environmental stimulus This model works both ways, so that information can be retrieved as well as stored Sensory memory Processing Short term memory Processing Long term memory

21. Improving Memory • Apply what psychologists have discovered to our own learning • REPTITION. If you have not remembered something you have read, read it several times • REHEARSAL. Read sections that are short enough to keep in your short term memory. Make notes from memory to help move the information into long term memory • ACTIVE MEMORY. Highlighter pens, mind maps and so on. These all help put information into long term memory for future use (getting information into long term memory is also better when associated with colour sound or smell)

22. GOOD LUCK IN THE EXAM