| What is plasticity? | Brain’s tendency to change and adapt (functionally and physically) as a result of experience and new learning. |
| What happens to the brain during infacny? | the brain experiences a rapid growth in the number of synaptic connections it has, peaking at approximately 15,000 by the age of 2-3 years old. - This is twice as many as there are in the adult brain |
| What is is called when connections are strengthened? | Cognitive pruning |
| When the brain in a continual state of change? | growth in early years to change and refinement in adulthood as we learn and experience. |
| What did Maguire study? | brains of London taxi drivers using an MRI and found significantly more grey matter in the posterior hippocampus than in the matched control group. |
| What is the grey matter in the posterior hippocampus do? | associated with the development of spatial and navigational skills in humans and other animals.
As part of their training London Cabbies must take a complex test called ‘the knowledge’, which assesses their recall of the city streets and possible routes. |
| What was seen with the longer the cab drivers have been doing their jobs? | the job the more pronounced was the structural difference (a positive correlation). |
| A strength of plasticity? | -May not decline sharpyl with age
-Bezzola demonstrated how 40 hr of golf training produced change in the neural representations in ppts aged 40-60
-Shown using fMRI scans which displayed motor activity in the novice golfers increased compared to a control group, positive effects after training
-Neural plasicity can continue throughout the lifespan |
| A strength of plasicity? | -Seasonal plassticiy occures in response to environmental changes
-Tramontin found that the SCN shrinks in spring and expands in autumn in songbrids
-Signficiant bc it provides further evidence that the brain is constantly adapting, even throughout the year
-Limitation is that it is conducted on animals, cannot extrapolate and generalise the findings to human beings due to being a differnece in behaviour, cognitive functioning and size and structure of their brains. |
| A weakness of plasicity? | -Negative behavioural consequences
-Brain's adaptation to prolonged drug us leads to poorer congnitive functioning later life
-Moreover, 60-80% of amputees have phantom limb syndrom (experience sensations in missing limb due to changes in somatosenroy cortex)
-Suggests that the brain's ability to adapt to damage is not always beneficial and lead to physical and psychological problems. |
| What is functional recovery? | A form of plasticity, the brain’s ability to redistribute or transfer functions: following damage through trauma. |
| What happens after truama? | forms of trauma such as infection or the experience of a stroke, unaffected areas are sometimes able to adapt or compensate for those areas that are damaged. |
| What is functional recovery an example of? | Neural plasicty. Happens quickly after trauma (spontaneous recovery) and then slow down after several weeks or montsh |
| How does the brain adapt? | Rewire and reorganises itself by forming new synaptic connections close to the area of damage.
Secondary neural pathways that would not typically be used to carry out certain functions are ‘unmasked’ to enable functioning to continue. This process is supported by a number of structural changes. |
| What is axonal sprouting? | Undamaged axons grow new nerve endings to reconnect neurons whose links were injured or severed. |
| What is denervation supersensitivty? | Axons that complete a similar job become aroused to compensate for those lost. |
| What is recruitment of homologous areas? | Regions on opposite sides of the brain take on functions of damaged areas. |
| A strength of functional recovery? | -Real world application
-Understanding plascitiy has led to neurorehabilitation techniques such as contraint induced movement threapy
-Significant as it can improve the quality of life for ppts suffering with limb dysfunction
-Showing that research into functional recovery helps medical professionals know when interventions can be made |
| Weakness of functional recovery? | -Nerual plasticiy may be related to cognitive reserve
-Schneider looked at the time brain injury ppts had spent in eduction (indication of cognitive reserve) and their chaces of a disability-free recovery (DFR).
-Finds shwoed that 40% of ppts who achieved DFR had more than 16 years of education comapred to 10% of ppts with less than 12 years
-Suggest that cognitive facotrs can impact biological structures in the brain and how well they recover. |
| A weakness of functional recovery? | -Findings are often significant, but the samples are small
-Eg: Banerjee found that recovery from stroke using stem cells led to total recovery compared to just 4% of normal recovery
-However, study drew conclusions based on just 5 ppts and no control group. Typical of functional recovery research as ppts are hard to recruit for research
-Reseach lack validity, but waiting for larger samples may prevent the development of valuable treatments. |
