Brain Plasticity

Question 1

Synaptic Connections Over Time

Answer 1

• During infancy, the brain grows in the number of synaptic connections (peaks to 15000 by 3 years old, which is twice as many as in adult brain – Gopnick et al in 1999)
• As we age, rarely used connections are deleted and frequently used connections are strengthened (synaptic pruning)

Question 2

Research About Changes

Answer 2

• Originally, it was thought that changes were restricted to developing the brain within childhood and that the adult brain, having moved beyond a critical period, would remain fixed and static in terms of function and structure
• More recent research suggests that at any time in life, existing neural connections can change and new ones can be formed as a result of learning (plasticity)

Question 3

Maguire et al (2000)

Answer 3

• Cabbies take a ‘Knowledge’ test, which alters the structure of the taxi drivers’ brains
• Found more volume of grey matter in posterior hippocampus of London taxi drivers than in a matched control group
• That part of the brain is associated with the development of spatial and navigational skills in humans and other animals

Question 4

Mechelli et al (2004)

Answer 4

• Found a larger parietal cortex in the brains of bilingual people compared to matched monolingual controls

Question 5

Draganski et al (2006)

Answer 5

• Found changes in the posterior hippocampus and parietal cortex of medical students 3 months before and after their final exams

Question 6

Functional Recovery

Answer 6

• After physical injury, unaffected/healthy areas of the brain are able to adapt and compensate for damaged areas
• Neuroscientists say this can happen very quickly (spontaneous recovery); it can then slow down which is when a patient may need rehab
• Brains can ‘rewire’ (Doidge 2007) – form new synaptic connections close to area of damage
• Structural changes in the brain are axonal sprouting, reformation of blood vessels, and recruitment of homologous areas

Question 7

Axonal Sprouting

Answer 7

• The growth of new nerve endings which connect with other undamaged nerve cells to form new neuronal pathways – a new route around affected area/s

Question 8

Blood Vessel Reformation

Answer 8

• AKA 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
• It can have the negative effect of oversensitivity

Question 9

Recruitment Of Homologous Areas

Answer 9

• Usage of opposite side of the brain to enable a pathway to go across