Plasticity + Trauma Flashcards
What is plasticity?
-the brains tendency to change + adapt as a result of experience and new learning
Opposes critical window theory
-opposes the idea that synaptic and neuronal connections to be made, must be in the first 3 years of life - after that = no more neuronal formations
What is synaptic pruning?
-controlling the strength and number of neuronal connections
-aging = rarely used = deleted
-frequently used = strengthen
Maguire’s study - support
-brains of London taxi drivers
-found lots of grey matter in posterior hippocampus
-associated with development of spatial + navigational skills
-positive correlation between grey matter and the longer they had been a taxi driver
-must complete ‘Knowledge test’ of recall of routes - shown to alter brain structure
-supports the idea of plasticity - demonstrates the brain can alter due to new learning
Draganski’s study
-imaged brains of medical students 3 months before + after final exams
-shown learning induced changes in hippocampus
-in posterior + parietal cortex
-suggests learning has induced changes in the structure of the brain
-supports plasticity
What is functional recovery?
-ability to redistribute functions usually performed by a damaged area or other undamaged areas
-enabled through law of equipotentiality
What happens in recovery?
-brain rewires itself by forming new synaptic connections to area of damage
-secondary neural pathways not usually used are activated to enable functioning
What are the 3 structural changes?
- Axonal sprouting
- Denervation super sensitivity
- Recruitment of homologous areas on the opposite side of the brain
What is axonal sprouting?
-growth of new nerve endings which connect tight other undamaged nerve endings
What is denervation super sensitivity?
-when similar axons become aroused to a higher level to compensate for the ones that are lost
-negative consequences; oversensitivity to messages = pain
What is recruitment of homologous areas?
-recruit on opposite side of brain - specific tasks can still be performed
What is a contradiction to plasticity?
-there are individual differences in plasticity
-plasticity tends to reduce with age - means that while it is maturing, recovery from trauma is more successful
-however there are neural changes in ppl 40-60 yrs old - suggets plasciticy still occurs across the lifespan
-women tend to recover more effectively that men as their function is not as lateralised
-suggests there are different factors involved in determining the plasticity of the brain
What is phantom limb disorder?
-contradiction to plasticity
-results from reorganisation in somato-sensory
-suggests there are different factors involved in determining plasticity
-prolonged drug use results in poor cognitive function
-event the brain may have some plasticity - process is not always successful = result in unwanted conditions
What is a practical application of plasticity?
-understanding processes in plasticity
-contributed to field of neuro rehab
-recovery slows after a period of time
-requires additional interventions - eg. Jodie Miller - needed additional therapy
-shows research in this area has important applications
What is an alternative to plasticity?
-stems cells implanted into brain help to treat brain damage - directly replace damaged cells
-stem cells - secrete growth factors that rescue injured cells
-form neural networks linking uninsured with damaged regions
