Plasticity Flashcards
what does it mean plasticity?
the brains tendency to change and adapt (functionally and physically) as a result of experience and new learning
what happens to the brain in infancy?
- the brain experiences a rapid growth in the number of synaptic connections it has.
- peaks at 15k at 2-3years.
what happens to the brain as we age?
- rarely used connections are deleted
- frequently used connections are strengthened in process of synaptic pruning
what does synaptic pruning do?
enables lifelong plasticity where neural connections are formed in response to new demands
what is the research into plasticity?
- part of training for London taxi drivers have to take test of ‘The Knowledge’ assessing recall of streets and routes
- structure of brains (hippocampus) changes
Maquire’s results of London Taxi Drivers
- more grey matter is posterior (back) hippocampus than matched control group (non-taxi). part of brain associated with development of spatial + nav skills
- pos correlation with volume in right posterior hippocampus + length of time driving. longer driver=more volume
- plasticity of hippocampus in response to environmental demands
evaluation of Maguire study
S: good design as many controls like matched for age, sex so can compare IV to DV
L: small sample size: generalisability issues, all males so diffs in gender with spaital memory
L: MRI costly, not ecomocially valid yet is objective
L: difficult to make conclusions: diffs found may not happened bc of IV (taxi vs no taxi), individual differences
supporting research into plasticity
Draganski et al
> brain images of medical students 3 months before + after final exams. found changes in posterior hippocampus and parietal cortex.
> brain change + adapt due to new learning
strength of plasticity
Practicla applications
understanding processes in plasticity helped neurorehab, techniques like electrical stimulation of brain. shows process requires further intervention if its to be successful
limitations of plasticity
- plasticity is potential negative consequences
- relationship between age + plasticity is complex
- brains ability to rewire has maladaptive behavioural consequences eg prolonged drug use=poorer cognitive functioning. processes may not be beneficial
- functional plasticity reduces with age, greater prosperity for reorganisation in childhood. C- research in 40yrs of golf training led to changes in neural rep of movement=throughout lifespan.
