biopsychology - plasticity and functional recovery of the brain Flashcards
what is plasticity
describes the brains tendancy to adapt and change as a result of experience and new learning - often involves growth of new connections
what is functional recovery
a form of plasticity following damage through trauma - the brain has the ability to redistribute or transfer functions to compensate for damaged areas
what is synaptic pruning
Rarely used synaptic connections are deleted and frequently used connections are strengthened.
when does synaptic pruning occur
as we age, during infancy the brain experiences rapid growth in the number of synaptic connections it has, twice as many as there is in an adult brain.
what does synaptic pruning enable
lifelong plasticity where new neural connections are formed in response to new demands on the brain
(AO3) what is the link between neuroplasticity and the nature/nurture debate - use maguire’s research to explain
environmental demand can cause change to biological structures and functions. New learning for taxi drivers (nurture) changed the structure of the hippocampus (nature) - interactionist approach
outline Maguire’s research into plasticity
Studied brain of taxi drivers before and after a complex test. Using an MRI scan maguire measured the volume of grey matter in the posterior hippocampus before and after, then compared this in a matched control group with non taxi drivers.
What did Maguire find about the plasticity of the brain in taxi drivers
found significantly more grey matter in posterior hippocampus than in the matched control group, Also found positive correlation between the time spent as a taxi driver and the increased size of the hippocampus, negative correlation with the anterior hippocampus
(AO3) what can we conclude from maguire’s findings
The change in environmental demand (learning new road maps) caused a structural change in the total volume of grey matter in the posterior hippocampus. This validates plasticity as shows the brain region changed over the period of learning as new connections formed. Further emphasised when they found the longer the taxi driver the greater the volume of posterior hippocampus
What were Draginski’s findings that support plasticity (AO3)
found that medical students experienced learning induced changes to the posterior hippocampus after the environmental demand of learning for their final exam. This further illustrates that learning influences structure and function of the brain which validates plasticity
what is functional recovery
is the transfer of functions from a damaged area of the brain after trauma, to other undamaged areas - an example of plasticity
what is neuronal unmasking
aids functional recovery where dormant synapses (which have not received enough input to be active), open connections to compensate for a damaged area of the brain.
list the 4 processes that occur during functional recovery
- axonal sprouting
-denervation super sensitivity
-recruitment of homologous areas
-reformation of blood vessels
what is axonal sprouting
growth of new nerve endings which connect to other undamaged nerve cells to create new neuronal pathways
what is denervation super sensitivity
occurs when axons that do a similar job become aroused to a higher level to compensate for the ones that are lost - can be maladaptive and lead to phantom leg syndrome
what is recruitment of homologous areas
If an area on the right side of the brain is damaged, the left would carry out the function and compensate.
outline a case study that provides support for functional recovery (AO3)
Cameron - rare case of right hemisphere completely removed due to severe epileptic seizures. Shows that recruitment of homologous areas is effective, her left hemisphere completely compensated for the removed right hemisphere which resulted in normal functioning.
what is a real world benefit of research into plasticity (AO3)
understanding the brain is capeable of functional recovery has lead to improvements in neurorehabilitation. resulted in effective treatments such as electrical stimulation and physical rehabilitation. This increases the efficacy of treatments and benefits more people.
Plasticity isn’t always beneficial, outline ways that plasticity can be maladaptive (AO3)
prolonged drug use damages neuronal connections, over time the brain adapts which results in a depleted cognitive reserve and results in poor cognitive functioning. Denervation super sensitivity can result in an oversensitivity to pain and can cause phantom leg syndrome which is extremely uncomfortable.
