Plasticity

Question 1

What is brain plasticity?

Answer 1

Refers to the brain’s ability to change and adapt due to experience

Question 2

How does the brain continue to change over time?

Answer 2

• Researchers used to believe that change only happened during infancy and childhood
• More recent research demonstrated that the brain continues to create new neural pathways and alter existing ones to adapt to new experiences due to learning

Question 3

What are different types of experiences that affect neuronal stucture?

Answer 3

• Life experience
• Video games
• Meditation

Question 4

How does plasticity occur as a result of life experience?

Answer 4

• As people gain new experiences, nerve pathways that are used often develop stronger connections, whereas neurons that are rarely or never used eventually die.
• By developing new connections and pruning away weak ones, the brain can constantly adapt to a changing environment

Question 5

Describe the study for plasticity due to life experience

Answer 5

• There’s a natural decline in cognitive functioning with age that can be attributed to changes in the brain
• This led to researchers to look for ways in which new connections can be made to reverse this effect
• Boyke et al found evidence of brain plasticity in 60 year olds taught a new skill (juggling). They found increases in grey matter in the visual cortex, but when practising stopped, changes were reversed

Question 6

How does plasticity occur as a result of playing video games?

Answer 6

Playing video games makes many different complex cognitive and motor demands

Question 7

Describe the study for plasticity due to playing video games

Answer 7

• Kuhn et al compared a control group with a video game training group that was trained for 2 months for at least 30 mins per day on Super Mario.
• They found a increase in grey matter in various brain areas including the cortex, hippocampus and cerebellum. This increase wasn’t evident in the control group that didn’t play Super Mario.
• Researchers concluded that video game training has resulted in new synaptic connections in brain areas involved in spatial navigation, strategic planning , working memory and motor performance (skills that were important in playing the game)

Question 8

Describe the study for plasticity due to mediation

Answer 8

• Researchers working with Tibetan monks have been able to to demonstrate that mediation can change the inner workings of the brain.
• Davidson et al compard 8 Tibetan monks with 10 student volunteers with no previous mediation experience. Both groups were fitted with electrical sensors and asked to mediate for a short time.
• The electrodes picked up much greater activation of gamma waves (important as they coordinate neuron activity) in the monks. Students showed a slight increase in gamma wave activity while mediating.
• Researchers concluded mediation changes the workings of the brain in the short term, and may also produce permanent changes, as the monks had more gamma wave activity even before they started meditating.

Question 9

Give evaluation for plasticity (animal studies)

Answer 9

• Kempermann et al suggesting that an enriched environment could alter the number of neurons in the brain
• They found evidence of more new neurons in the brains of rats housed in complex environments compared to rats housed in laboratory cages.
• Rats in complex environments showed an increase in neurons in the hippocampus, a part of the brain associated with the formation of new memories and the ability to navigate from one location to another
• This shows the brain’s ability to change due to experience (plasticity)

Question 10

Give evaluation for plasticity (human studies)

Answer 10

• Maguire et al, in a study of London taxi drivers, found changes in the brain could be detected due to their extensive experience of spatial navigation
• Using a MRI scanner, researchers calculated the amount of grey matter in the brains of taxi drivers and a set of control participants.
• The posterior hippocampi of taxi drivers were much larger relative to those of control participants and posterior hippocampal volume was positively correlated with the amount of time they had spent as a taxi driver
• This shows that hippocampal volume was greater in those individuals with job-related experience of spatial navigation, but also that the highest levels of plasticity were evident in those more extensive experience