Plasticity and Functional Recover Flashcards
Plasticity
Our brain adapts according to the environment, which can change the structure and the function of the brain. For instance, having traumatic events (car crashes) would change brain structure as learning and developing a new skill can change the function of the brain. An example of neural plasticity can be seen through this idea of functional recovery. This is when the healthy parts of the brain compensate for the damaged parts by doing their functions. This can occur very fast after the trauma but then eventually will slow down.
Synaptic Pruning
Old & unused connections are replaced by constantly used connections, thus strengthening them. Bridging is when new connections are formed because of a new stimulus. Children have more connections and as they grow older, they will have fewer connections which are much stronger. Neurons can also regenerate to replace the old lost or damaged ones. And forming these new connections can change the structure of the brain.
Events during recovery
The brain is able to rewire and reorganise itself by forming new connections. There will also be neural pathways, that would not have been used to carry out certain functions, would be activated to allow the functioning to carry on in the same way as before the damage had occurred. There are other structural changes that will occur:
Axonal sprouting
The neurons will grow axons to connect with undamaged neurons to form new neural pathways.
Denervation supersensitivity
Axons that do a similar job would be aroused to compensate for the axons that are lost, but this can result in oversensitivity to things like pain.
Homologous Areas Recruitment (on the opposite side of the brain)
This allows specific tasks to still be performed, for instance, if Broca’s area on the left was damaged, the right could still carry out its functions and after a period of time, the function would shift back to the left, thus showing plasticity of the brain.
+ PRACTICAL APPLICATION of NEUROREHABILITATION
There is a practical application of neurorehabilitation. A person’s brain and activity will slow for a few weeks after injury so physical therapies are required to maintain improvements in functions, or the suffering could worsen. For instance, some therapists have used constraint-induced movement therapy to encourage patients to use their damaged parts of the body whilst keeping their undamaged parts restrained. This, therefore, is a strength as it shows how it has allowed medical professionals to develop interventions to ensure that functional recovery is always a success. Moreover, this also suggests though nature and internal factors may play a big role in recovery, it still requires the aid of external factors to fully fix the damage, thus also contributing to nature and nurture theory. Overall, it clearly has positive economic implications as it allows functioning members to return back to the society to contribute to its economy rather than relying upon unemployment or benefits, thus benefiting to wider society.
- MALADAPTIVE CONSEQUENCES
Rewiring can have maladaptive consequences. Ramachandran et al found 60-80% of amputees developed a phantom limb syndrome where they could still feel their limb. This reflects poor patient mental health as the somatosensory cortex is damaged, and therefore suggests that the brain may rewire incorrectly sometimes. This is a limitation as it highlights how the brain does not respond in the same way for everyone or every damage and therefore has negative implications as it can make individuals think they have fully recovered even though they have not. Nevertheless, sociologists could perhaps view this in a positive light as it could lead to a self-fulfilling prophecy where the patients feeling of being ‘healthy’ and ‘fine’ would manifest as they keep telling themselves they are normal once again.
+ ANIMAL STUDIES RESEARCH
Research support is provided through animal studies; Hubel et al sewed one eye of a kitten shut and analysed the brain’s cortical response. They found that the area of the visual cortex which was associated with the shut-eye was not lazy and continued to process information from the open eye. This is important in supporting the idea of plasticity because it shows how the brain can change to compensate for the damage that has occurred in other areas. But, a limitation of using animal studies is that there is an issue with extrapolation, as although animals and humans are similar, they have many differences and these differences must be considered before making a generational study. Due to this issue, one could argue that the theory is invalid and cannot be generalised.
+ RESEARCH SUPPORT for ADAPTION
Kuhn et al. found a significant increase in grey matter in various regions of the brain after participants played video games for 30 minutes a day over a two-month period. Similarly, Davidson et al. demonstrated the permanent change in the brain generated by prolonged meditation: Buddhist monks who meditated frequently had much greater activation of gamma waves (which coordinate neural activity) than did students with no experience of meditation. These two studies highlight the idea of plasticity and the brain’s ability to adapt as a result of new experiences, whether it’s video games or mediation.
