Plasticity and functional recovery Flashcards
What is plasticity
The ability of the brain to change shape and adapt to its environment
What did Maguire et al. explore in plasticity
He examined the brains of London taxi driver which showed an enlarged hippocampus(increased grey matter)
The longer they had done the job, the more pronounced the structural difference
What did Draganski et al study into plasticity
He imaged medical students brains 3 months before and after final exams. Learning induced changes seen in the posterior hippocampus and parietal lobe
What did Mechelli et al find in plasticity
Larger parietal lobe in bilingual- suggests plasticity as brain has adapted with learning multiple languages
What is functional recovery
After trauma, unaffected areas of the brain can adapt and compensate for damaged areas. This can occur quickly(spontaneous recovery) or take months(may need rehabilitative support)
What are the 3 structural changes that can occur due to functional recovery
Axonal sprouting- growth of new nerve endings which connect with undamaged to create new neural pathways
Reformation of new blood vessels
Recruitment of homologous areas on the side of the brain to perform specific tasks
Who is Gabby Gilllard?
A former US Democratic politician who survived an assassination attempt in 2011 when she was shot in the head at blank range. In months, she made astonishing progress and with the aid lof physical rehabilitation she was able to walk under supervision with perfect control of her left arm and leg.
Who is Jodie Miller
A girl with Rasmussen Encephalitis causing her to lose control of the left side of the body. She had the right side of her brain removed to treat seizures. Her right side of the brain filled up with sinal fluid and her left hemisphere took control over her whole body.
What are the strengths of functional recovery and plasticity
It contributed to the field of neurorehabilitation- Movement therapy, electrical stimulation of the brain to counter cognitive deficiencies following strokes. Spontaneous recovery appears to slow after a few weeks so rehabilitative therapy can further recovery
Functional plasticity reduces with age- brain is greater at reorganisation as a young child as always adapting and lots of new experiences
Bezzola(2012)
* 40 hours of golf training produced changes in neural representation of participants aged 40-60
* fMRI showed reduced motor cortex activity in novice golfers compared to control group, shows more efficient neural representations after training
Demonstrates neural plasticity lasts throughout lifetime
What are the weaknesses of functional recovery and plasticity
Brain wiring can be maladaptive- Prolonged drugs use results in poorer cognitive functioning and increased risk of dementia
60-80% of amputees develop phantom limb syndrome which can be unpleasant and painful- thought to be due to cortical reorganisation in the somatosensory cortex occurring as a result of limb loss
Case studies
Animal studies-Hubel and Wiesel(1963)
* Sewed the eye of a kitten shut and analysed cortical responses
* Visual cortex for shut eye continued to process stimuli from other eye
* But cannot generalise to humans and cats were not born without an eye
