Maguire (2000)

Question 1

(Maguire) Define the term ‘white matter’.

Answer 1

Appears white due to the fatty
myelin insulation on the neurons. This transfers information to other locations.

Question 1

(Maguire) Define the term ‘grey matter’.

Answer 1

Tissue in the nervous system that appears grey because it is
composed of numerous nerve cell bodies. This is involved in
processing information in the brain.

Question 2

(Maguire) Define and explain what the hippocampus is.

Answer 2

Part of the brain within the limbic system.
It is split into different parts (the anterior, front part, main body and posterior, back part) which are thought to have
slightly different functions in memory and navigation.

Question 3

(Maguire) What did studies in animals show about the sections of the hippocampus?

Answer 3

That the hippocampus can enlarge when the animal’s territorial map was large.

Question 4

(Maguire) What was the aim of this study?

Answer 4

Maguire wanted to find out whether the hippocampus might also show plasticity among humans.

Question 5

(Maguire) Describe the sample of the taxi drivers. (6)

Answer 5

• 16 male London taxi drivers
• All right handed
• Between ages 32 and 62
• Been licensed for at least 18 months (range: 18 months to 42 years)
• All passed ‘The Knowledge’
• All healthy medically, neurologically and psychologically

Question 6

(Maguire) Describe the control group for this study.

Answer 6

• Researchers selected 50 scans from the MRI database at the centre where the taxi drivers were scanned (only 16 scans were used for pixel counting).
• All were healthy right-handed males aged between 32 and 62.
• None of the control scans were from taxi drivers.

Question 7

(Maguire) State and explain what type of experiment this study was.

Answer 7

Quasi Experiment
The IV was whether they were a taxi driver or not. This was not manipulated by Maguire.

Question 8

(Maguire) Explain how this study used matched groups.

Answer 8

The taxi drivers and controls were matched on age, sex and being right handed.

Question 9

(Maguire) Why was a structural MRI used in this study?

Answer 9

Structural MRI was used to show the structure of the
hippocampus not how it
worked.

Question 10

(Maguire) What 2 methods were used to analyse data, and state with method is established and which is new.

Answer 10

1. Pixel Counting - established
2. Voxel Based Morphometry (VBM) - new method

Question 11

(Maguire) Describe and explain the established method of ‘Pixel Counting’.

Answer 11

• This was carried out by one experienced analyst who did not know whether the scan came from a taxi driver or a control participant.
• A pixel is a 2D measure of area (i.e. the number of individual dots that make up the image).
• The scans were separated into
  26 ‘slices’ of the hippocampus –
  and the number of pixels in the
  posterior/anterior and main body counted so differences in
  these areas could be detected.

Question 12

(Maguire) Describe and explain the new method of ‘Voxel Based Morphometry’.

Answer 12

• This is an objective 3D measure of the volume of grey matter in the brain (calculated from the MRI scans by computer). The computer program looks at all the slices together and calculates if there are any differences in volume of grey matter.

Question 13

(Maguire) Why did the study use 2 measures?

Answer 13

Using 2 measures (one established and one new) increases concurrent validity.

Question 14

(Maguire) State and explain the results from the VBM. (2)

Answer 14

• Taxi drivers had an increased volume of grey matter in the posterior hippocampus.
• Taxi drivers had a decreased volume of grey matter in the anterior hippocampus.

Question 15

(Maguire) State and explain the results from the Pixel Counting. (2)

Answer 15

• Taxi drivers had bigger area in their posterior hippocampus.
• The controls had more area in the right side of the hippocampus than the left (whereas the taxi drivers had no significant difference).

Question 16

(Maguire) State and explain the results regarding the ‘posterior’.

Answer 16

Length of time as a taxi driver
positively correlated to the volume of their right posterior hippocampus.

Question 17

(Maguire) State and explain the results regarding the ‘anterior’.

Answer 17

Length of time as a taxi driver
negatively correlated to the
volume of their right anterior.

Question 18

(Maguire) State the 2 conclusions from this study.

Answer 18

• The study showed regional differences between the hippocampi of London taxi drivers compared to a control group of non-taxi drivers.
• It seems that relying on navigational skills as part of your job is associated with a redistribution of grey matter in the hippocampus (from the anterior to the posterior hippocampus).

Question 19

(Maguire) What are the roles of the Hippocampus for the posterior and the anterior.

Answer 19

Posterior: Is used when previous learning is required.
Anterior: Is used when learning
new environmental layouts.

Question 20

(Maguire) How does this study relate to the nature/nurture debate?

Answer 20

Nurture: The taxi driver’s brains
are not naturally that way but instead change as a result of their job.

Question 21

(Maguire) How does this study relate to the determinism/holism debate?

Answer 21

Deterministic: The size of the sections in the hippocampus is
determined by the spatial memory needs of the person’s job.

Question 22

(Maguire) How does this study relate to the individual/situational debate?

Answer 22

Situational: The size of the posterior/anterior hippocampus is influenced by the situation of their daily role.

Question 23

(Maguire) How does this study relate to the socially sensitive debate?

Answer 23

The study can be seen as socially sensitive may feel anxious about a deficit they have in learning new things as a result of their job.

Question 24

(Maguire) How does this study relate to the biological area?

Answer 24

Falls into the biological area as it suggests that the ability to navigate different routes and maps is related to a specific region of the brain – the hippocampus.

Question 25

(Maguire) How HAS this study changed our understanding of Brain Plasticity?

Answer 25

Adds to Blakemore and Cooper’s findings in confirming that neuroplasticity can also
occur in the brain of humans (specifically in the hippocampus).

Question 26

(Maguire) How HASN’T this study changed our understanding of Brain Plasticity?

Answer 26

Does not necessarily show that the visual neurons of humans would show the same kind of neuroplasticity (humans exposed to a limited visual
environment might not show the same visual deficits as found in the kittens).