plasticity and functional recovery of brain after trauma Flashcards
what is brain plasticity?
- describes brains tendency to change and adapt (functionally and physically) as a result of experience and new learning
brain plasticity- other points
- brain keep changing till our 40s
- in infancy we have 15,000 synaptic connections (2x as much as adult brain)
- synaptic pruning = we use fewer connections as age so they die off
what are the different researches into plasticity?
maguire et al
dragonski et al
michelli et al
plasticity- what did Maguire et al find?
- studied brains of London taxi drivers and they had much more grey matter in posterior hippocampus (brain area linked to spatial navigation) —> the longer they had done the job= the more pronounced the structural difference (positive correlation)
plasticity what did Dragonski et al find?
- jugglers had more grey matter at end of study compared to control group
- images of medical students 3 months before and after final exams —> learning induced changes= seen in posterior hippocampus and parietal lobe
plasticity what did Mechelli et al find?
- larger parietal lobe in bilingual = plasticity of brain adapted with learning multiple languages
what is neuroplasticity?
- brains ability to adapt and to change structural plasticity = changes within brain structures
what is functional recovery of brain after trauma?
- brains ability to replace lost/damaged functions after trauma e.g. stroke by using existing brain regions= compensate for damaged areas —> shows neuroplasticity
how fast is functional recovery after trauma
- can occur quickly (spontaneous recovery) or slow (may need rehabilitative support)
- the brain can rewire and organise by forming new synaptic connections close to damaged area. Secondary neural pathways are activated/ unwashed to enable continued functioning
- younger age= easier for recovery to occur
functional recovery after trauma- what are the 3 structural changes in the brain?
- axonal sprouting- growth of new nerve endings which connect with undamaged to create new neural pathways
- reformation of blood vessels (repair themselves)
- recruitment of homologous areas (similar areas) as other side of brain to perform specific tasks
real life examples of functional recovery of brain after trauma
Gabby Giffords- US democratic politician
Jodie Miller
functional recovery of brain after trauma- Gabby Giffords
- US democratic politician- shot in head (assassination attempt)- put in coma and within months made lots of recovery with aid of physical rehabilitation –> she could walk, write, read, speak short phrases
functional recovery of brain after trauma- Jodie Miller
- 3 year old with Ramusen Encephalitis and seizures –> lost control of left side of body and right side of brain removed to treat seizures, her left hemisphere completely took control of her whole body and filled with cerebral spinal fluid= she was able to function and move left side of her body
eval point 1
practical applications
- neurorehabilitation
- rehabilitative therapy can further recovery
–> following illness/injury to brain recovery tends to slow after a few weeks so needs physical therapy to maintain improvements in functioning –> e.g. movement therapy
–> brain can fix itself but may need support
eval point 2
negative plasticity
- brain rewiring can be maladaptive –> prolonged drug use= poorer cognition functioning and increased risk of dementia (Medina et al)
eval point 3
- age and plasticity
- functional plasticity reduces with age as it’s constantly adapting to new learning etc –> Bezzola et al showed 40 hours of golf training changes neural representation of ppts aged 40-60
–> fMRI showed reduced motor cortex activity in novice golfers compared to control group= more efficient neural representations after training –> shows neural plasticity lasts a lifetime
eval point 4
- animal studies
–> Hubel and Wiesel sewed eye of a kitten shut and analysed coticol responses –> visual cortex for shut eye continued to process stimuli from other eye –> BUT NOT A HUMAN
eval point 5
- cognitive reserve
–> educational attainment= could influence how well brain adapts functionally after injury –> Schneider et al found more time brain injury patients spend in education= greater chance of disability free-recovery
–> 769 patients, 214 DFR after 1 year of these 39.2% had 16+ years in education and had DFR only 9.7% DFR with less than 12 years
BUT other factors may have influenced recovery from brian injury (diet etc)
eval point 6
Kepperman et al –> said enriched environments could alter number of neurons in brain –> rats in complex environment vs cages –> showed greater neurons in hippocampus (associated with memory formation)
