biopsychology - plasticity and functional recovery of the brain

Question 1

what is plasticity

Answer 1

describes the brains tendancy to adapt and change as a result of experience and new learning - often involves growth of new connections

Question 2

what is functional recovery

Answer 2

a form of plasticity following damage through trauma - the brain has the ability to redistribute or transfer functions to compensate for damaged areas

Question 3

what is synaptic pruning

Answer 3

Rarely used synaptic connections are deleted and frequently used connections are strengthened.

Question 4

when does synaptic pruning occur

Answer 4

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.

Question 5

what does synaptic pruning enable

Answer 5

lifelong plasticity where new neural connections are formed in response to new demands on the brain

Question 6

(AO3) what is the link between neuroplasticity and the nature/nurture debate - use maguire’s research to explain

Answer 6

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

Question 7

outline Maguire’s research into plasticity

Answer 7

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.

Question 8

What did Maguire find about the plasticity of the brain in taxi drivers

Answer 8

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

Question 9

(AO3) what can we conclude from maguire’s findings

Answer 9

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

Question 10

What were Draginski’s findings that support plasticity (AO3)

Answer 10

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

Question 11

what is functional recovery

Answer 11

is the transfer of functions from a damaged area of the brain after trauma, to other undamaged areas - an example of plasticity

Question 12

what is neuronal unmasking

Answer 12

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.

Question 13

list the 4 processes that occur during functional recovery

Answer 13

• axonal sprouting
  -denervation super sensitivity
  -recruitment of homologous areas
  -reformation of blood vessels

Question 14

what is axonal sprouting

Answer 14

growth of new nerve endings which connect to other undamaged nerve cells to create new neuronal pathways

Question 15

what is denervation super sensitivity

Answer 15

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

Question 16

what is recruitment of homologous areas

Answer 16

If an area on the right side of the brain is damaged, the left would carry out the function and compensate.

Question 17

outline a case study that provides support for functional recovery (AO3)

Answer 17

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.

Question 18

what is a real world benefit of research into plasticity (AO3)

Answer 18

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.

Question 19

Plasticity isn’t always beneficial, outline ways that plasticity can be maladaptive (AO3)

Answer 19

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.