9- Plasticity Throughout the Lifespan

Question 1

How long does the brain retain the ability for plasticity?

Answer 1

Throughout the lifespan

Question 2

Who studied neurogenesis?

Answer 2

Draganski et al, 2004

Question 3

What did Draganski et al study?

Answer 3

Juggling training in adult humans

Question 4

What did Draganski et al find?

Answer 4

Increased brain volume in hippocampus

Question 5

How did Draganski et al see that neurogenesis effects persisted?

Answer 5

Neurogenesis effects still present 3 months after end of training

Question 6

What did Draganski et al’s study suggest?

Answer 6

Adult hippocampus can grow new neurons

Question 7

What did Draganski et al’s study support?

Answer 7

Learning from practice and experience

Question 8

What are stem cells?

Answer 8

Building blocks for all cells

Question 9

What can neural stem cells generate in the CNS?

Answer 9

Neural progenitor cells

Question 10

What can neural stem cells in the CNS create?

Answer 10

New neurons and glial cells in developing and adult brains

Question 11

What did Altman and Das discover about adult neurogenesis by studying the rodent brain?

Answer 11

Formation of new neurons in the dentate gyrus of the hippocampus

Question 12

How long do new cells take to fully mature?

Answer 12

Up to 2 months

Question 13

What suggests that neurons in the hippocampus have a role in learning and memory?

Answer 13

New neurons go through a phase of increased synaptic plasticity

Question 14

Where does neurogenesis seem to occur mostly?

Answer 14

In the hippocampus

Question 15

What is hippocampal neurogenesis dependent on?

Answer 15

Activity/environment

Question 16

How is hippocampal neurogenesis regulated by?

Answer 16

Physiological and pharmacological stimuli

Question 17

What did Maguire et al study?

Answer 17

London taxi drivers

Question 18

What is the learning that London taxi drivers go through that causes learning through experience?

Answer 18

Taking ‘The Knowledge’- learning to navigate and remember routes around London

Question 19

How did Maguire et al measure hippocampal volume?

Answer 19

MRI

Question 20

Who were Maguire et al’s controls?

Answer 20

Bus drivers

Question 21

What did Maguire et al find in London taxi drivers?

Answer 21

Enlarged hippocampus in more experienced drivers

Question 22

What did Maguire et al’s study suggest?

Answer 22

Learning can promote neurogenesis

Question 23

How did London taxi drivers compare to experience-matched bus drivers?

Answer 23

London taxi drivers had larger posterior hippocampus

Question 24

What does experience of drivers correlate with?

Answer 24

Larger posterior hippocampus

Question 25

How was neurogenesis studied in 38 medical students?

Answer 25

An MRI structural scan 3 months before medical exam, day after the exam, and 3 months later

Question 26

How did hippocampal volume change between time points when medical students were studied?

Answer 26

Increased

Question 27

What was studying medical students good evidence for?

Answer 27

Learning-induced plasticity in young adulthood

Question 28

How long does maturation of new neurons require?

Answer 28

Several weeks to months

Question 29

How did Van Praag study neurogenesis?

Answer 29

Lab rodents were given access to a running wheel that stimulated hippocampal neurogenesis

Question 30

What result did exercise have on neurogenesis in humans?

Answer 30

Increasing hippocampal volume

Question 31

What does the hippocampus tend to do as we age?

Answer 31

Shrink

Question 32

What could explain why some older people have similar hippocampal volumes to individuals who are younger?

Answer 32

Hippocampal neurogenesis

Question 33

What is hippocampal neurogenesis linked to?

Answer 33

Better memory in later life

Question 34

Who show less decline in cognitive performance as they get older?

Answer 34

People who are physically active in later life

Question 35

How does the brain try and maintain good function as someone ages?

Answer 35

Brain compensates for effects of aging

Question 36

What changes take place in normal aging in the brain?

Answer 36

Neurochemical and synaptic changes

Question 37

How much does the brain shrink on average between the ages of 20 and 90?

Answer 37

5% to 10%

Question 38

What deteriorates in the brain in normal aging?

Answer 38

White matter fibres

Question 39

What suggests the potential for the brain to adapt?

Answer 39

Some older individuals maintain excellent cognition

Question 40

What do 'cognitive reserve' models suggest?

Answer 40

Brain has a 'buffer' and can adapt and compensate for aging

Question 41

What do fMRI studies show happens to the brain as we get older?

Answer 41

Brain activates more brain regions with age

Question 42

What led to the 'hemispheric asymmetry reduction'?

Answer 42

fMRI studies show that older adults additionally recruit the other hemisphere

Question 43

What can TMS be used to do?

Answer 43

Temporarily disrupt a brain mechanism

Question 44

How is TMS applied to study compensation in the aging brain?

Answer 44

To left or right PFC in a recognition memory task

Question 45

What was the result of TMS on subjects aged less then 45?

Answer 45

Disrupting the right PFC affected performance

Question 46

What was the result of TMS on subjects over 50?

Answer 46

Disrupting either hemisphere PFC affected performance

Question 47

How did evidence suggest that the brain has a compensatory mechanism in aging?

Answer 47

Suggestion that older adults are using both hemispheres to perform the task

Question 48

What does aging do to brain structure?

Answer 48

Undermines it

Question 49

How are compensatory mechanisms enhanced?

Answer 49

By stimulatory experience

Question 50

What kind of structure is the brain?

Answer 50

A highly adaptive structure that changes in both positive and negative ways across the lifespan

Question 51

What drives synaptic pruning?

Answer 51

Experience

Question 52

What does synaptic pruning lead to?

Answer 52

A more efficient brain

Question 53

What does experience cause in adulthood?

Answer 53

Reorganisation of relevant cortical areas

Question 54

What does plasticity allow in adulthood?

Answer 54

Brain to respond to injury

Question 55

What promotes neurogenesis in the hippocampus?

Answer 55

Experience, learning and physical exercise

Question 56

What can neurogenesis in the hippocampus help maintain?

Answer 56

Cognitive function with aging

Question 57

How is plasticity also seen in later life?

Answer 57

As additional brain regions are used to compensate for effects of aging