Plasticity and Functional Recovery Flashcards
What is plasticity?
the brains tendency to change and adapt as a result of experience and new learning; generally the growth of new connections
What is synaptic pruning
process in the adult brain that enables life long plasticity
rarely-used connections are deleted and frequently-used connections are strengthened
Discuss research into Plasticity
Maguire et al
conducted structural MRI scans on 16 male London taxi drivers and found significantly more volume of grey matter in their posterior hippocampus compared to 16 male matched non taxi drivers
posterior hippocampus is associated with spatial and navigational skills
Taxi drivers take a knowledge test as part of their training which assesses their recall of streets and routes
Maguire found this learning alters the structure of taxi drivers brain
Also found the size of their posterior hippocampus was reflective on how long they had done the job (positive correlation)
Maguires research suggests the brain is plastic and able to configure itself to its environment and psychological demands
What additional research is there on brain plasticity
Draganski et al
imaged the brain of medical students three months after and before their exams
learning induced changes were seen to have occurred in the posterior hippocampus and parietal cortex
What is axonal sprouting
existing neurons grow new axons to connect to adjacent neurons
What is denervation supersensitivity
to compensate for the loss of axons in a pathway, remaining axons become more sensitive sometimes resulting in side effects like pain
What is functional recovery
form of plasticity
healthy areas of the brain compensate for the lost or damaged areas
What is meant by spontaneous recovery
recovery can occur quickly after trauma
however this may slow down after several months leading the individual to require rehabilitative therapy to further this recovery
What is meant by recruitment of homologous areas on opposite side of the brain
specific tasks can still be carried out on the other side of the brain
(eg if Broca’s area was damaged on the left side of the brain, the right sided equivalent would carry out its function, after time functionality may shift back)
What 3 processes occur during brain recovery
axonal sprouting
denervation supersensitivity
recruitment of homologous areas on opposite side of the brain
what factors affect functional recovery
age - children have better ability to recover
gender - women more able to recover from brain damage
What is a strength of Plasticity
Bezzola et al
Pp aged 40-60 underwent 40 hours of golf training which ultimately produced increased activity in their motor cortex (viewed through fMRI) in contrast to novice golfers
demonstrated more efficient neural representations after training
shows neural plasticity can continued throughout the lifespan
What is a limitation of plasticity
may have negative behaviour consequences
60-80% of amputees develop phantom limb syndrome; continued unpleasant sensations in the missing limb as if it were still there; thought to be due to cortical reorganisation in the somatosensory cortex
suggest brains ability to adapt to damage is not always beneficial
What is a strength of Functional Recovery
Real world application
neuro rehabilitation/constraint induced movement therapy with stroke patients
repeatedly practice using the affected body part whilst the unaffected is restrained
shows functional recovery is useful as it helps medical professionals know when interventions need to be made
What is a limitation of functional recovery
cognitive reserve
level of education may influence recovery rates
Schneider et al found the more time people with a brain injury spent in education the greater their chances of a disability free recovery
40% of people who achieved DFR has 16 years of education compared to 10% of those who had less then 12 years
