Plasticity And Functional Recovery Flashcards
Brain plasticity can be defined as…
- The brains ability to change and adapt (functionally and physically)as a result of experience and new learning
- e.g. language centres - in left hemisphere - if damaged right could take over
What is experience expectant plasticity?
Changes in the brain that take place during infancy. The brain grows a lot in infancy when the brain is exposed to the environment and learns new things
What is experience dependent plasticity?
The brain continues to create new neural pathways and alter existing ones. This is as a result of learning and life experiences.
What is Synaptogenisis?
Where new synapses are formed. This can occur throughout life but during infancy there’s an explosion of synaptic formation (known as exuberant synaptogenisis)
What is Neurogenisis?
This refers to when new neurons are grown. In infancy this is responsible for populating the growing brain with neurons. But also occurs in adulthood
What is synaptic pruning (or axon pruning) ?
The process of synapse elimination that typically happens between early childhood and the onset of puberty. However this has also been shown to occur to a lesser extent in adulthood
Trigger for change : Infancy (experience expectant)
Findings :
Conclusions :
- the brain experiences rapid growth in the number of synaptic connections it has,peaking at approximately 15,000 by 2-3, this is twice the adult brain. As we age rarely used connections are deleted and frequently used ones are strengthened
- Plasticity is at its peak in childhood
Trigger for change : Computer gaming
Findings :
Conclusions :
- Kunn et al illustrated the potential benefits of playing super Mario for two months (at least 30 mins). They found significant increases in areas of the brain (hippocampus, cerebellum) responsible for working memory, motor performance and planning
- Brains are strengthened when learning and practicing certain skills
Trigger for change : Taxi driving
Findings :
Conclusions :
- Maguire studied London taxi drivers brain using an MRI and found significantly more grey matter in the posterior hippocampus than in the control group. This part of the brain is associated with the development of spatial/navigational skills
- occupations lead to synaptogenesis as you are learning new skills
Trigger for change : Spending months on a space station
Findings :
Conclusions :
- Kopplemans no gravity effects in space and how this effects the brain. 27 astronauts scanned before and after space mission. Between 2 weeks - 6 months in space. Cerebellum (co-ordination) shrunk - positively correlated with time in space - motor + somatosensory regions swelled
- even space travel can have profound short term effects on the brains plasticity
What is Functional recovery?
Individuals may experience loss of brain functioning and unaffected areas may adapt and compensate for the areas which are damaged. Functional recovery is an example of neural plasticity
What is neural regeneration ?
- This is also known as axon sprouting and occurs when new nerve endings grow and connect with undamaged areas
- this can compensate for damaged areas and enable the recovery of previously lost functioning
- this can be seen as a type of synaptogenisis
What is neuronal unmasking?
- This occurs when dormant synapses in the brain are opened and become functional
- this can occur when a surrounding brain area becomes damaged as the rate of input to these dormant synapses would increase opening connections to regions of the brain that are not normally activated and allowing the gradual development of new structure
- type of synaptogenisis/neurogenisis
What is neural reorganisation?
- This occurs when the brain transfers functions from the damaged area to the undamaged sections of the brain
- for example if Broca’s area was damaged than an area on the right hemisphere might take over
- in extreme cases whole areas of the brain can take over the functions of damaged sections
Describe Danelli’s (2013) case study
- investigated case of Italian boy (EB) who had most of his;eft hemisphere removed aged 2.5 to remove tumour
- with intensive therapy his right hemisphere was able to take over almost all of the functioning that his left would’ve normally done
- this is largely because EB’s brain would’ve shown maximal plasticity (the younger you are the more you have)
