plasticity and functional recovery

plasticity

refers to brains ability to change and adapt due to prior experience

* research has shown brain can create new neural pathways, and alter existing ones to adapt to new experienced as a result of learning

life experience

frequent use of neural pathways strengthens them and therefore, if they’re not used, die out

age > has a huge effect on plasticity

tuning

building new neural pathways

pruning

removing weak pathways

Boyke et al 2008

* found plasticity was evident in 60 year old’s when learning how to juggle.
* grey matter in visual cortex increased when learning to juggle, but stopped and then the grey matter reversed
* > shows decrease in cognitive function throughout latter years of life.

(factors affecting plasticity) Khun et al: video games

playing video games uses many different complex cognitive and motor demands

* Khun et al - 2 seperate groups, one played super mario for 30 mins a day for 2 months, the other didnt.
* after 2 months, group 1 had increased grey atter in cerebellum and vital cortexes in the brain
* > concluded that playing video games creates new synaptic connections centred around skills such as strategic planning.

(factors affecting plasticity) Davidson et al: meditation

* compared 8 Tibetan monks who regularly meditated to 10 student volunteers with no meditation experience
* both groups were fitted with electrical sensors and asked to meditate for short periods of time
* found that gamma wave activity was significantly higher in Tibetan monks, before and after the research
* > concluded that meditation can have impact on both short term and long term aspects of neural activity

(P) AO3: research support from animal studies

**Kempermann et al 1998** - ‘enriched environments can alter number of neurons in the brain’

* found increased number of neurons and neurotic
* transmission in rats that were housed in complex environments, compared to rats in lab cages
* > provides clear evidence for plasticity and brains ability to adapt and change

(P) AO3: research support from human studies

**Maguire et al 2000** - studied London taxi drivers

* used MRI scans, found that taxi drivers have significantly larger grey matter than those in the control group of participants
* > further reinforced by experience - taxi drivers for longer had larger hippocampi due to more exposure to constant aspects of spatial navigation

functional recovery

* idea that the brain can move functions from damaged areas to undamaged areas to in efficiency
* evident in stroke victims who are able to regain aspects of function within their brain due to functional recovery

2 ways functional recovery is possible:

* neural unmasking
* stem cells

neural unmasking

* Wall 1977 - identified dormant synapses in the brain - synaptic connections that exist anatomically but function is blocked
* increased rate of input to these synapses can unmask them
* the unmasking of these synapses can open connections to parts of the brain that are not normally activated

stem cells

unspecialised cells that are able to differentiate to carry out different functions


1. stem cells implanted into brain will directly reduce dead or dying cells.
2. transplanted stem cells secrete growth factors that can ‘rescue’ the injured cells.
3. transplanted cells form neural network which links an uninjured brain site, where new stem cells are made, with the undamaged regions of the brain.

(FR) AO3: research support from animal studies

**Tajiri et al 2013** - did research on 2 rats with traumatic brain injuries

* one rat had stem cells implanted into brain, the other can clear harmless solution injected into brain with no stem cells
* 3 months later, the rat with stem cells showed clear development of neuron-like cells in the area of the injury, and the stem cells were containing the region of injury
* > supporting the role of stem cells in functional recovery

(FR) AO3: research support from human studies

Elbert et al 2001 - age differences

argues that the capacity for neural reorganisation is much greater in children than in adults.

the younger you are the more likely you are to recover from a brain injury

traumatic brain injury is significantly more fatal as people grow olde, as most suggest that compensatory behaviour strategies are the only way of dealing with brain injuries after childhood