lof Flashcards
lof intro
Localization of function is the idea that different parts of the brain serve diff functions/ is responsible for diff things, e.g
Limbic system/ amygdala controls emotion- e.g sharots study where amygdala only active in ppl closest to the scene
Hippocampus- HM. required for consolidation of memeory and moving of memory, not responsible for memory itself?
Localization of function can offer some explanation as to why people behave the way they do. The theory may offer some advice as to hwo to deal with patients with traumatic brain injuries or illnesses. If we are able to target and identify certain areas and what function they served, we may be able to address these problems.
Assuming that LOF can account for all behaviours, the fact that a lot of behaviours are influenced y lots of other factors like social or environmental factors. Implications that if LOF can explain our behaviour, we wont take responsibility for actions such as murder. Decideing to what extent its our fault can help us determine what level of responsibility to take for legal issues.
Bidirectional ambiguity- e.g raine, where they did brain scans on people who were murderers. Is it the thinking that triggers the brain, or is it the brain that triggers that type of behaviour. Could be a general problem with this bidirectional ambiguity
maguire
Maguire- shows the relative localisation of function as the brain adapts through neuroplasticity.
London taxi cab drivers mastering the knowledge
Aim: to see if the brains of taxi drivers in london would be diff as a result of training to study the knowledge.
Drivers had a larger hippocampus- larger spatial map. Causes connections to develop and grow and makes hippocampus bigger
Suggests adult brain can refashion structure based on owners needs
Redistribution of matter.
Shows neuroplasticty AND localization of function
Procedure-
MRI scan of 16 right handed male london taxi drivers (biased sample actually more representative of the people as taxi drivers, and to make sure no other variables and 50 non taxi drivers. ) Taxi drivers had to have compeleted the knowledge tet and have had license for 1.5 years. Controls were taken from mri database. Used range od ages
Reseachers looked to see if there was relationship between no. of years driving taxi and anatomy of brain. Single blind study, researcher didnt know which brain they were looking at
Measured density of grey matter in brain and used pixel counting to calculate area of hippocampus
Results
Posterior hippocampus of taxi drivers significantly larger than controls, anterior hippocampus significantly smaller.
Volume of right posterior hippocampus correlated with amount of time spent as taxi driver
No diff in other parts of brain.
Conclusion
Possible change in brain was due to accomodating environemntal demands.
Posterior hippocampus used when recalling previous spatial info, anterior hippocampus might be more involved in encoding of new environmental layout
Evaluation
Quasi-experiment. Cant decide whos a taxi driver and whos not a taxi driver. Cant be cause and effect. Cant manipulate IV
Small sample size of taxi drivers
LArge age group range used
Taxi drivers male and right handed, could say not generalisable. HOWEVER, this was done as this was actually more reperesentative of the actual population of taxi drivers
Correlational study- cant say for sure use of spatial navigation in brain causes change in brain
Another explanation is that it could be that ppl with these brains are more inclined towards jobs that are navigational. Cant be sure as we didnt create the situation
^ However, they tested taxi drivers brains as well as how long theyve been drivers for, and there is a correlation between hippocampal volume and how long theyve been driving for. The longer they spent driving taxi, the bigger the change. Continual correlation between longer u drive and bigger parts of the brain. Still doesnt show cause and effect, could be the physical act of driving cars, or maps, or older ppl have bigger changes.
^ However, They made sure they had a range of age groups to make sure it wasnt a figure of too old and young. A younger ppl could also have spent longer driving a taxi than older people. Still doesnt SHOW cause and effect.
Possible that it was the physical drivign that causes changes in brain, rather than the thinking and navigating routes
Cant see changes in brain, just the pic of the brain
Single blind- researchers didnt know whether they were looking at taxi or non taxi brain
They used pixel counting of brain. They counted ind squares of brain/ spatial resolution of mri scan (counted every millimeter dot of the hippocampus). Got someone else to do pixel counting, and didnt know what brain they were lookign at. GOOD
No issue of ecological validity- they didnt ask them to do anything.
Sampling bias- kind of, but not really
Ethically sound, mri has no health risk
Eleanor Maguire
Taxi drivers and bus drivers.
Taxi drivers go round diff routes, bus drivers go the same route, but both physically drive the same amount
If it was about driving, both brains would change the same way, if there was a difference, there would be a diff redistribution of matter
Study showed that there was a diff redistribution of matter
COnclusion- shows localization of brain for hippocampus and that posterior hippocampus is the part responsible for navigational memory. Doesnt show STRICT localization, as brian physically changes based on what you do. The area of brain responsible for it is a bit flexible, and study highlights the complexity of it
