Maguire

Question 0

Hypothosis

Answer 0

. The hippocampi London taxi drivers will be structurally different to the hippocampi of non-taxi drivers

Question 1

Background & aim

Answer 1

. Does the structure of your brain change to environmental demand?
. The aim was to find out whether changes in the brain could be detected in those with extensive navigation experience

Question 2

Method & design

Answer 2

. Quasi experiment
. Matched pairs design
. Correlation between length of time taxi-driving and olume of grey matter

Question 3

Sample

Answer 3

. Group 1: 16 right handed, male taxi drivers, avg age 44, all licensed more than 18 months, avg time as taxi driver 14.3 years

. Group 2: 50 right handed, male, age matched, non-taxi drivers - chosen from database at the same unit where taxi drivers were scanned

Question 4

Variables

Answer 4

IV: London taxi driver (brain) or non taxi driver (brain)

DV: structure and volume of hippocampi

Question 5

Procedure

Answer 5

. Image acquisition: structural MRI scans obtained of 50 non taxi drivers to establish a comparison database of ‘average hippocampi’.
- the taxi drivers also scanned
. Analysis: Voxel-based morphology (VBM) used to measure density of grey matter in the brain
- VBM provides 3D measurement of volume of an area
. Analysis: pixel counting carried out on 16 TD and 16 age matched NTD. It is a 2D measurement of an area. The scan separated into 16 slices

. Control: expert conducting analysis did not know whether MRI scan was of taxi driver brain or not

Question 6

Results

Answer 6

. VBM found that TD have a greater volume of grey matter in their right posterior hippocampus
- control had greater volume of grey matter in their anterior hippocampus
. Pixel counting supported this also
. Positive correlation: as length of time as a TD increased, volume of grey matter in right posterior hippocampus increased / volume of grey matter in anterior hippocampus decreased

Question 7

Conclusions & implications

Answer 7

. Structure of the brain changes in response to environmental demand
. Mental map of london stored in posterior hippocampi in taxi drivers
. Normal activity can induce changes in structure of brain and that this has many implications for rehab after brain injury