Recap of Psychological Investigations

1. Physiological ApproachMaguire (2000) Navigation-related structural changes in the hippocampi of taxi drivers.

2. Recap of Psychological Investigations We’re going to play a version of a game called ARTICULATE. • Get into groups of 3 or 4. • Your team needs to write 25 terms related to Psychological Investigations i.e. observations, self-reports and correlations • Each team will take it in turns for one member to describe a key terms to their team mates who have to guess which key term they are describing. • RULES = You can’t say the words written on the card, you can’t say sounds like, you can’t say begins with and each player can have one pass. TIMER http://www.classtools.net/education-games-php/timer

3. Assumptions of Physiological approach • Much of human behaviour has a biological base. • Psychologists should study the brain, nervous system and other biological systems, e.g. hormones • Which side would it tend to take in the nature-nurture debate? • NATURE

4. Maguire (2000)Navigation-related structural changes in the hippocampi of taxi drivers. This study looks at the brains of London taxi drivers and examines the role of the hippocampusin helping them to navigate their way around the city.

5. Learning ObjectivesBy the end of the lesson you will be able to … • Discuss the structure and function of the hippocampus in relation to spatial memory and navigation. • Outline the research procedure including the two MRI scanning techniques used. • Describe the results of the study. • Outline the conclusions drawn from this study.

6. Lobes of the brain and functions https://www.youtube.com/watch?v=Vy8EvyQoQIE (From 1 minute). As you watch, complete the handout on the lobes of the brain and their function.

7. Maguire (2000) What is the hippocampus? Located in the mid temporal lobe Hippocampus is the Latin word for seahorse.

8. Each hemisphere of brain has one. 2 x hippocampus = hippocampi Maguire (2000) What is the hippocampus? In the brain, the hippocampus plays a key role in spatial memory and navigation.

9. What is spatial memory? How long does it take you to complete the maze? How did you do this? What skills did you use?

10. The solution

11. Complete the maze again How long does it take you this time? Why does it take less time to complete the second time?

12. In pairsMake your own plasticine model of the brain and hippocampus

13. On your tables Put these techniques of measuring the brain in the order you think they were developed.

14. Brief history of brain measurement • Early 1800’s Phrenology - linking bumps on a person's head to certain aspects of the individual's personality and character. • 1848Phineas Gage - using brain damaged patients. • 1870sElectrical stimulation of the brain - to produce certain reactions. • 1920s Electroencephalogram (EEG) • 1930s Prefrontal lobotomies

15. Brief history of brain measurement • 1970s Computerised axial tomography (CAT) - x-ray of soft tissue). • Late 1970s Positron emission tomography (PET) -uses radiation to produce images of body tissue. • 1980sMagnetic Resonance Imaging (MRI) - uses magnetic fields and radio waves to produce images of the inside of the body. • 1990sFunctional Magnetic Resonance Imaging(fMRI) – uses MRI to measure brain activity).

16. How do we know about the function of the hippocampus? Human case study (1926-2008) • Video of HM https://www.youtube.com/watch?v=KkaXNvzE4pk

17. How do we know about the function of the hippocampus? Animal studies • Animals that have a large territory have larger hippocampi. • Small mammals and birds who engage in lots of food storage have a larger hippocampal volume. • Racing pigeons renowned for their skill at flying home long distances from unknown locations have larger hippocampi than other breeds of pigeon.

18. Which jobs might require more spatial memory than others? DELIVERY DRIVERS PILOTS POSTMEN (AND WOMEN) SAILORS LORRY DRIVERS TAXI DRIVERS

19. Maguire (2000) – Navigation skills in Taxi Drivers The Knowledge: Black Cab drivers are required to have a detailed knowledge of the 25,000 streets within a six-mile radius of Charing Cross as well as a more general knowledge of the major routes throughout the rest of London.

20. Maguire (2000) – Navigation skills in Taxi Drivers Video of taxi drivers learning ‘The Knowledge’. https://www.youtube.com/watch?v=wF8UcEHZjmg&eurl=http://www.psychexchange.co.uk/videos/view/20196/&feature=player_embedded Think about • What is ‘The Knowledge’? • How long does the process take? • How are drivers assessed?

21. In pairsTaking it in turns, I would like you to work out the quickest route from A – B on Map 1 and memorise this route (including street names). You will have 2 minutes to do this. Then I would like you to tell your partner this route (without looking!)

22. Now do the same for Map 2 Was this task difficult? Was Map 1 or Map 2 hardest? Why?

23. To investigate the role of the hippocampus in navigational and spatial skills, and the extent to which the brain shows changes (plasticity) when exposed to extensive navigational experience, as demonstrated by London taxi drivers. Also, to see if there is a correlation between the length of taxi-driving experience and the measure of grey matter volume. What type of correlation might we expect? Maguire (2000) – Aim

24. Maguire (2000) - Sample • 16 male licensed London taxi drivers. • Right-handed. • Aged between 32 and 62 (mean age of 44 years). • Healthy medical, neurological and psychiatric profiles. • All had been licensed for at least 18 months, (range 18 months- 42 years, mean = 14.3 years).

25. Maguire (2000) – Sample • A comparison group of 50 control participants were chosen from the structural MRI scan database at the same unit where the taxi drivers were scanned. • All Male and healthy. • Non were taxi drivers. • Right-handed • Aged between 32 and 62. (Mean age similar to taxi drivers)

26. Maguire (2000) – Method and Design • Naturally occurring IV. • Relationship between time spent as taxi driver and size of hippocampus. • Taxi drivers and non taxi drivers. • The volume of the hippocampus. • INDEPENDENT MEASURES because … • The method is best described as a QUASI EXPERIMENT because……. • AND it also involves aCORRELATIONAL ANALYSIS of …. • The IV is … • The DV is …. • The design is ….

27. Maguire (2000) – Procedure • Data was collected using MRI (Magnetic Resonance Imaging) scans. http://www.youtube.com/watch?v=H5q79R9C-mk

28. Maguire (2000) – Procedure • MRI scans were obtained. • The scans were analysed using two techniques: 1. VBM (Voxel-Based Morphometry) 2. Pixel counting.

29. Maguire (2000) – Procedure 1st Technique – Voxel-Based Morphometry. • Produces a 3D image measuring the volume of an area. • Identifies differences in density (amount) of grey matter in different areas of the brain. • Grey matter has dense neural connections and is associated with higher order thinking.

30. Maguire (2000) – Procedure 2nd Technique - Pixel Counting. Produces a 2D image and measures the volume of the hippocampus • A pixel is a single point on a graphic image. • In order to calculate hippocampal area, pixels were counted on photographic ‘slices’ made through the brain using an MRI scan. • The person counting the pixels was ‘blind’ to whether the brain belonged to a taxi driver or control participant. • Pixels were counted for the anterior, posterior and body of the hippocampus.

31. Measure the volume of the hippocampus of your brain using a ruler. Voxel-based Morphometry

32. Pixel Counting Lie your hippocampus flat, cut it into thin slices, prod those pieces as many times as you can with a toothpick and count the dots.

33. Maguire (2000) – Procedure • CONTROLS • Participants had all been scanned using the same scanner. • The hippocampal volume for each participant was calculated to include an adjustment for the size of each person’s brain. This was to ensure that all participants data was comparable.

34. Handout with key terms and definitions

35. Posters/Drawing Task • VBM Taxi drivers and Controls 2) PC Taxi drivers and Controls 3) Correlations

36. Maguire (2000)VBM Results Taxi drivers Showed significantly increased grey matter volume in left and right posterior hippocampi. Controls Had relatively greater grey matter volume in the right and left anterior hippocampi. Other differences? No other differences found between their brains.

37. Maguire (2000)Pixel Counting Results Overall There was no significant difference in the total volume of the hippocampi in the controls and the taxi drivers. Taxi drivers The posterior hippocampi had greater volume than the controls. Controls Greater volume in anterior and body of hippocampi and in both cases the right was larger than the left.

38. Handout to label on hippocampus where the differences were found

39. Maguire (2000) Results

40. Maguire (2000) Results • Correlational Analysis – a comparison of length of driving experience with the measure of grey matter volume of the taxi drivers showed: A positive correlation between length of time as taxi driver and volume of right posterior hippocampus. A negative correlation between length of time as taxi driver and volume of right anterior hippocampus.

41. What do the results from the correlation mean? • This means the more experienced the driver is, the greater the grey matter volume is in their right posterior hippocampus and the less grey matter volume there is in their rightanterior hippocampus. • Suggests that there was no overall increase in the volume of grey matter in the hippocampi of taxi drivers – it had been redistributed.

42. Correlational results on handout

43. Maguire (2000) - Conclusions • Maguire states ‘professional dependence on navigational skills in licensed London taxi drivers is associated with a relative redistribution of grey matter in the hippocampus’.

44. EXPLANATIONS FOR RESULTS. 1. This difference in the taxi drivers’ hippocampi might have always been there and this could have led them to doing a job where navigational skills were important...... OR 2. The taxi drivers’ hippocampi may have changed as a result of studying for the ‘knowledge’ and working as taxi drivers thus showing plasticityof the brain. Maguire (2000) - Conclusions Which is nature and which is nurture?

45. Maguire (2000) - Conclusions • The results of the correlational analysis would support the second idea – because the longer they had been a cab driver, the greater the volume of their right posterior hippocampus.

46. Different roles of anterior and posterior hippocampus • Anterior: This is used when encoding new spatial information, which is more common with people who learn new locations all the time (Non-taxi drivers). • Posterior: This is used when previously learned spatial information is used (Going over ‘the Knowledge’ in taxi-drivers).

47. Different roles of left and right side of hippocampus Right hippocampus Holds mental maps Left hippocampus Complements its partner by storing memories i.e. people and events that occur in the taxi drivers world (but not necessarily into an existing map).

48. Learning ObjectivesBy the end of the lesson you will be able to … • Discuss the structure and function of the hippocampus in relation to spatial memory and navigation. • Outline the research procedure including the two MRI scanning techniques used. • Describe the results of the study. • Outline the conclusions drawn from this study.

49. Quiz on what we’ve learned today

50. Question 1 – The taxi drivers were • Male, right-handed and aged 32-62. • Male, right-handed and aged 44-62. • Male, left-handed and aged 44-62. • Female and male, left-handed and aged 32-62.