2b. Neuroplasticity

Question 1

Neuroplasticity

Answer 1

The ability of the brain to alter its own structure following changes within the body or in the external environment

Question 2

What part of the neurons are grey and white matter?

Answer 2

Grey matter: Cell bodies

White matter: Myelin sheaths and axon

Question 3

Synaptic plasticity

Answer 3

The ability of a single neuron to form new synaptic connections and break up the old ones

Question 4

When is a connection formed between two nearby neurons?

Answer 4

When the two neurons are frequently fired in response to multiple action potentials

Question 5

Cortical remapping

Answer 5

Phenomenon when brain area X assumed the function of brain area Y possibly due to injuries or other causes

Question 6

Who performed the juggling experiment?

Answer 6

Draganski et al. (2004)

Question 7

Draganski: Aim

Answer 7

Study to find out whether human brain can really change in response to environmental demands

Question 8

Draganski: How were groups allocated?

Answer 8

Used a self-selected sample and random sampling design where volunteers were randomly allocated to two conditions.

Question 9

Draganski: Process

Answer 9

• MRI performed before
• Juggler group spent 3 months learning juggling and second MRI was taken
• They than spent next 3 months not juggling and third MRI was taken
• Control groups just went about daily lives for 6 months and MRIs were taken at same intervals

Question 10

Draganski: What characteristics did participants require?

Answer 10

No prior experience to juggling

Question 11

Draganski: Results of first MRI

Answer 11

Comparisons of first brain scans were similar

Question 12

Draganski: Results of second MRI

Answer 12

Second scan showed more grey matter in juggling group than control group in the mid temporal area (both hemispheres).

Question 13

Draganski: Results of third MRI

Answer 13

Showed decrease in grey matter in juggling group but still greater than the control group

Question 14

Draganski: What is mid-temporal area associated with?

Answer 14

Coordination of movement

Question 15

Draganski: Analysis

Answer 15

• Brain changes are more pronounced in those who trained better
• Certain areas of brain grow in response to learning
• Failure to practice meant they shrink back significantly though not to initial state

Question 16

Who performed the London taxi driver experiment?

Answer 16

Maguire et al

Question 17

Maguire: Aim

Answer 17

To see relationship between number of years of experience with taxi driving and anatomy of one’s brain

Question 18

Maguire: Participants

Answer 18

• 16 right handed male licensed drivers. Average years of experience around 14 years
• Control: 50 right handed male drives between 30-60 years of age who didn’t drive a taxi

Question 19

Maguire: Results

Answer 19

• Increased grey matter in posterior hippocampus for taxi drivers but decreased in anterior
• Increased grey matter in anterior hippocampus for control
• No difference in overall volume just redistribution of volume

Question 20

Maguire: Process

Answer 20

• Took scans from a a database
• Data was measured using voxel-based morphology and pixel counting
• VBM was used to measure density of grey matter
• Pixel counting calculated area of hippocampus using pixels in images

Question 21

Maguire: Quasi or lab?

Answer 21

Quasi as they didn’t randomly assign people, differences already existed. Study was correlational

Question 22

Maguire: Alternative explanation for results

Answer 22

Taxi drivers have redistribution but what if those born with larger grey matter in posterior hippocampus tend to choose professions based in navigations?

Question 23

Maguire: How did he falsify alternative explanation?

Answer 23

Examined correlation between hippocampal volume and time spent as a taxi driver

Question 24

Maguire: Result of correlational test

Answer 24

• Positive correlation between posterior hippocampus and time spent as a taxi driver
• Negative with anterior for taxi drivers
• Showed result of neuroplasticity

Question 25

Maguire: Accepted conclusion

Answer 25

P. hippocampus is involved with previously learned spatial information while a. hippocampus deals with learning new spatial information

Question 26

Neural networks

Answer 26

When a neuron is stimulated, an action potential travels down the axon. Neural networks are created when a neuron or set of neurons are repeatedly stimulated

Question 27

Long term potentiation

Answer 27

Neurons start to sprout more dendrites to adapt. This means increases in number of synapses available for certain behavior

Question 28

Synaptic pruning

Answer 28

Process by which extra neurons and synaptic connections are eliminated in order to increase the efficiency of neuronal transmissions. Results from reduced potentiation