topic 8 neuroplasticity

Question 1

what is neuroplasticity

Answer 1

the physical and chemical changes in the nervous system in response to changes in the external environment

Question 2

what changes are neuroplasticity involved in

Answer 2

1. neuronal numbers due to apoptosis and neurogenesis
2. axon number and length
3. synapse number and type- reconfiguration of old circuits and creation of new circuits

Question 3

what is neuroplasticity driven by

Answer 3

• experience dependent changes associated with neuronal activity
• drug dependent changes
• developmental program
• disease or injury

Question 4

what can neuroplasticity result in

Answer 4

• subtle chemical changes at the synapse
• large macrostructural changes detected by MRI
• Transient or permanent irreversible changes such as altered gene expression

Question 5

where was the increased grey matter in london taxi drivers?

Answer 5

anterior hippocampus

Question 6

what were the brain changes associated with learning juggling?

Answer 6

Increased grey matter in the mid-temporal area, left posterior and intraparietal sulcus

Question 7

describe the impact of improved environmental enrichment in mice

Answer 7

Improved environmental enrichment:

• more room to roam
• more places to hide
• spatial complexity
• navigational demand

led to increased:

• dendritic spines
• synapses per neuron
• expression of trophic factors
• altered cortical maps
• neurogenesis

Question 8

what is sensitisation

Answer 8

a progressively greater behavioural response from the same stimulus

Question 9

what are brain changes involved in physical and sexual abuse and neglect

Answer 9

• decreased surface area and cortical thickness in frontal-temporal regions
• increased cortical thickness in occipital regions
• increased surface area in frontal regions

Question 10

what is the period between late gestation and early adulthood characterised by

Answer 10

neuronal loss
net synaptic loss
synaptic rearrangement
synaptic segregation
synaptic convergence

Question 11

what are changes in brain structures associated with mindfulness?

Answer 11

anterior cingulate cortex which is associated with attention

posterior cingulate cortex and prefrontal cortex associated with self awareness

fronto limbic network associated with emotion control

Question 12

what has mindfulness shown to be clinically beneficial for

Answer 12

risk of:
school faliure
adhd
anxiety
depression
drug abuse

Question 13

what percentage of the variation in adult height is influenced by genetics?

Answer 13

20%

Question 14

how is DNA methylation involved in learning and memory formation

Answer 14

• methyltransferase can methylate DNA nucleotides

- this can control synaptic scaling and glutamate receptor formation and is generally considered irreversible

Question 15

whats an example of DNA methylation impact

Answer 15

24 hours after fear conditioning, 9.2% of genes in rat hippocampus neurons are differently methylated

Question 16

are methylation and acetylation reversible or irreversible?

Answer 16

methylation is generally considered irreversible

acetylation is reversible

Question 17

what is a neurotrophic factor of neuroplasticity

Answer 17

• when neuronal cells are stimulated they increase production of BDNF
• this can lead to changes in a number of things such as dendritic spines
• it can also increase the number of AMPA receptors on the postsynaptic membrane
• its also good for neurogenesis and neural survival
• essentially BDNF strengthens synapses

Question 18

how does habituation work

Answer 18

prolonged stimulation leads to less neurotransmitter release and a weakened onward response

Question 19

what is homologous area adaptation?

Answer 19

• a particular cognitive process is taken up by a homologous region in the opposite hemisphere

Question 20

what is cross modal reassignment

Answer 20

structures previously devoted to processing one form of sensory input now accepting input from a new sensory modality

Question 21

what is map expansion?

Answer 21

enlargement of a functional brain region on the basis of performance

Question 22

what is a compensatory masquerade

Answer 22

novel allocation of a particular cognitive process to perform a task

Question 23

what is cross modal plasticity?

Answer 23

• the enhancement of remaining abilities to compensate for a function that is lost

Question 24

what happens 8 weeks following a stroke?

Answer 24

• a refinement of synaptic connection occurs
• there is a greater specifity in sensory responses
• some neurons are rewired to process information from the damaged region
• neurons are now selective for sensory input