Plasticity of the Brain Flashcards
What happens to the brain during infancy?
The brain experiences rapid growth in synaptic transmission, peaking at about 15 000 at the age of 2-3 (Gopnik)
What happens to the synaptic connections as we age?
Rarely-used connections are deleted and frequently used connections are strengthened - synaptic pruning.
Are these changes limited to childhood?
NO - once thought they were, but recent research suggests neural connections can change or be formed at any time due to learning & experience.
Who supports the concept of plasticty?
Maguire et al and his taxi driver study.
What did Maguire et al find?
Significantly more volume of grey matter in the posterior hippocampus in London taxi drivers’ than in a matched control group.
What is the posterior hippocampus liked to?
The development of spatial and navigational tasks.
What training did London cabbies go through?
They took a complex test called “The Knowledge” to assess their recall of city streets and possible routes.
What did the test do to cabbies’ brains?
Appears to have altered the structure of their brains. The longer they had been in the job, the more pronounced this structural difference was.
Who supports plasticity with research on learning?
Draganski et al
What did Draganski do?
Imaged the brains of medical students 3 months before & after final exams.
What did Draganski find?
Learning-induced changes were seen in the posterior hippocampus & the parietal cortex, presumably as a result of learning for the exam.
Limitation of plasticity?
Possible negative behavioural consequences.
Limitation of plasticity? Elab
The brain’s adaption to prolonged drug use leads to poorer cognitive functioning in later life, as well as an increased risk of dementia (Medina et al). 60-80% of amputees have phantom limb syndrome (experience sensations in missing limb due to changes in somatosensory cortex). This suggests that the brain’s ability to adapt to damage is not always beneficial & may lead to physical & physiological problems.
Strength of plasticty?
It may not decline sharply with age.
Strength of plasticty? Elab
Ladina & Benzolla et al demonstrated how 40 hours of gold training produced changes in the neural representations in participants aged 40-60. Using fMRI, motor cortex activity in the novice golfers increased compared to a control group, suggesting positive effects after training. This shows that neural plasticity can continue throughout the lifespan
