Biological area: Maguire Flashcards
What was Maguire’s aim?
To investigate differences in the brain of London taxi drivers also to investigate the function of the hippocampus in the spatial memory of the brain (can it change response to learning)
What was Maguire’s experimental method?
Quasi experiment and a correlation
What evidence is there that Maguire’s study was a quasi experiment?
Sample of taxi driver was naturally occurring this was not manipulated by the experimenter
What experimental design was used?
Independent measures
Who made up the experimental group in Maguire’s study?
16 male taxi drivers
Describe 3 characteristics of the taxi drivers?
All right handed, all healthy and all male
What was the age range of the taxi drivers?
32-62
What was the name of the London taxi test which they had all passed?
‘The knowledge’
How long had the taxi drivers been licensed for as a minimum?
18 months - 42 years
Who made up the non experimental group in Magurie’s study?
The non-taxi drivers
How many MRI scans were selected and then how many of those were matched to the taxi drivers?
50 were selected and 16 of those were matched
Describe 3 characteristics of the non experimental group
All right handed, all healthy and all male
What are 2 strengths of the sample used?
Controlled for extraneous variables and consistent sample
What are 3 weaknesses of the sample?
Not very big, only men and not applicable to all ages
What type of brain scan was used and why?
MRI scan because they were choosing to calculate the volume of grey matter in the hippocampus
What was the 3D technique used to calculate the volume of grey matter in the hippocampus?
Voxel-based morphometry (VBM)
What does VBM allow for?
Allows for a computer program to calculate the volume of area, in this case the grey matter in brain structural MRI scans
Who carried out the pixel counting?
One person experienced in the technique and blinded to the participants’ identity as a taxi driver or control
How many slices was the brain scan split into for the purpose for pixel counting?
26
How were the slices divided between the posterior, main body and anterior?
Posterior - 6 slices
Main body - 12 slices
Anterior - 6 slices
Why were 2 ways used to analyse the data?
To improve concurrent validity and VBM was a new test so they wanted to make sure it was accurate
What were some of the controls used in Maguire’s study?
Age, Gender, Right handed, Healthy, Passing the knowledge
What were the results found from VBM analysis?
Taxi drivers had increased grey matter on both sides of the posterior hippocampus but a decrease in grey matter in the anterior hippocampus in both sides
What were the results found from the pixel counting in regards to overall volume of the hippocampus between taxi drivers and non taxi drivers?
There was no difference in overall volume in both sides
What were the results found from the pixel counting in regards to the anterior hippocampus?
Non taxi drivers had higher volume in the right side
What were the results found from the pixel counting in regards to the posterior hippocampus?
Taxi drivers had higher volume of grey matter in the posterior hippocampus
In terms of the correlational analysis, where was a positive correlation found?
Between the length of time as a taxi driver and the volume of grey matter in the right posterior hippocampus
In terms of the correlational analysis, where was a negative correlation found?
Between length of time as a taxi driver (in months) and the volume of grey matter in the right anterior hippocampus
What did Maguire’s study show in terms of regional differences in the brain?
That there were regional differences between the structure of the hippocampus in taxi drivers to the control group
What idea did Maguire’s study support?
The idea that the brain has changed in response to the demands of being a taxi driver because as time spent in the job increases so does the demand on spatial memory
According to Maguire’s study, does the brain have plasticity and what can it do?
Yes and it can change to meet the demands of the environment
How do the findings support previous research using animals and patients with brain damage?
These findings are consistent with research on animals and also with patients who have suffered brain damage
What are differences between the anterior and posterior hippocampus?
Posterior is involved with previously learned material whereas the anterior is linked to learning about new environmental layouts
What are differences between left and right hippocampus functioning?
Suggests the right holds mental maps and the left holds memories and events not dependent on mental maps
What does the correlational data not show about the hippocampus?
Doesn’t show changes in the brain over time
Were any ethical guidelines broken by Maguire?
N/a
Were ethical guidelines upheld by Maguire?
It was carried out according to the British Psychological society’s (1993) ethical guidelines so there were no concerns
Was the procedure standardised and replicable? (internal reliability)
Highly controlled and collected quantitative data
Was the sample large enough to suggest a consistent? (external reliability)
No, only 16 London taxi drivers analysed so it’s hard to see consistency
Was it an accurate test of plasticity of the brain? (internal validity)
Yes highly controlled for extraneous variables
On what grounds on Maguire’s research be accused of cultural bias?
Because only looked into taxi
How/why might Maguire claim that their research is not ethnocentric?
Brain plasticity and the structure of the hippocampus is not likely to be specific to culture drivers in London
