Plasticity

Question 1

What is plasticity?

Answer 1

The brain’s capacity to reorganize and adapt after damage is known as neuroplasticity or brain plasticity.

Question 2

How does Neuroplasticity occur?

Answer 2

Neuroplasticity occurs due to learning, experience, and memory formation or due to damage to the brain.

Question 3

What is synaptic pruning?

Answer 3

Learning and new experiences cause new neural pathways to strengthen, whereas neural pathways used infrequently become weak and eventually die.

Question 4

Uses of neuroplasticity and research.

Answer 4

Neuroplasticity provides protective effects in managing traumas during human development (Cioni et al., 2011).

Also, learning music or second languages can increase neuroplasticity (Herholtz & Zatorre, 2012).

Question 5

What is functional recovery?

Answer 5

It is a form of plasticity, following damage through trauma, the brains ability to redistribute or transfer functions usually performed by a damaged areas to other undamaged areas.

Question 6

Gopink et al (1999) findings

Answer 6

Rapid growth of synaptic connections to about 15,000 by age 2-3, x2 the amount of a usual adult. Frequently used synapses are strengthened and others are pruned.

Question 7

Key study: Maguire et al (2000)

Answer 7

They found a Significantly higher volume of grey matter in the posterior hippocampus than in matched control group.

Learning experiences altering the structure of the taxi drivers brain, the longer they had been in the job the more pronounced the structural differences, (positive correlation)

Question 8

Research support for Maguire et al (2000)

Answer 8

Draganski et al (2006)
-Imaged medical students brains
-Learning induced changes occurred on the posterior hippocampus and the parietal cortex due to the build up for the exams.

Kuhn et al.
-significant inc in grey matter in various regions of the brain after p’s played video games for 30 mins a day over two-month period.

Question 9

What is Phantom limb syndrome?

Answer 9

Phantom limb syndrome can be understood as the brain’s attempt to adapt to the loss of a limb, often resulting in pain and other sensations because neural pathways continue to send signals to the missing body part. Sensations due to cortical reorganization in the somatosensory cortex that occurs as a result of limb loss (Ramachandra and Hirstein 1998)

Question 10

Links between age and plasticity?

Answer 10

Functional plasticity tends to reduce with age.

Linda Bezolla et al (2012) demonstrate how 40 hours of golf training produces changes in the neural representation of movement in participants aged 40-60. FMRI scans observed changes in motor cortex activity in new golfers compared to a control group- more efficient neural representations after training- plasticity does continue throughout lifespan but must account for individual differences

Question 11

What is neuronal unmasking?

Answer 11

Where inactive synapses which have not received enough input to be active, open connections to compensate for a nearby damaged area of the brain.

Allowing for new connections in the brain to be activated.

Process can occur quickly after trauma (spontaneous recovery) and then slow down after a few weeks, may need rehabilitative therapy to further their recovery.

Question 12

What happens to the brain during recovery?

Answer 12

Brain is able to rewire and reorganize itself by forming synaptic connections close to the area of damage.
Secondary neural pathways that would typically be used to carry out certain functions are activated ‘unmasked’ to enable functioning to continue

This is supported by a number pf structural changes

Axonal sprouting

Recruitment of homologous

Reformation of blood cells

Question 13

What is axonal sprouting?

Answer 13

Growth of new nerve endings which connect with other undamaged nerve cells to form neural pathways.

Occurs mostly two weeks after damage happens

Question 14

What is regeneration in axonal sprouting?

Answer 14

When the damaged nerve regrows its nerve ending to allow for nerves to travel.

Question 15

What is compensatory sprouting in axonal sprouting?

Answer 15

When an adjacent nerve grows another neve ending to create a new pathway for the nerve.

Question 16

What is recruitment of homologous.

Answer 16

Areas on the opposite side of the brain to perform similar tasks.

After a period of time, functionality may then shift back to the left side.

Question 17

Gender differences in recovery?

Answer 17

Woman recover better from brain injury as their function is not lateralized (coordinated in one hemisphere).

Patients with brain trauma were examined for their level of response for cognitive skills to rehabilitation.

When assessed for cognitive skills, woman performed significantly better than men on tests of attention/working memory and language, whereas men outperformed females in visual analytic skills.

However studies didn’t account for skills pre injury

Question 18

Evaluation for plasticity: Research Evidence

Answer 18

P: A strength is that there is research support of the idea of brain plasticity.

E: Kuhn et al. found a significant increase in grey matter in various
regions of the brain after participants played video games for 30
minutes a day over a two-month period.

L: Kuhn provides clear evidence for the idea of brain plasticity and shows
how experience can cause structural changes in the brain.

Question 19

Evaluation for plasticity: Further Research Evidence with reductionism

Answer 19

P: There is further research support for the notion of brain plasticity.

E: Evidence for plasticity comes from the study by Maguire et al (2000) who found increased grey matter in the brains of taxi drivers compared to the controls (the right and left hippocampi). Also, a positive correlation was found between the amount of time spent as a taxi driver and volume in the posterior right hippocampus.

I&D: However, some psychologists suggest that research investigating the plasticity of the brain is limited. E.g. Maguire’ study is biologically reductionist as it only examines a single biological factor (size of hippocampus) in relation to spatial memory. It fails to take in to account all of the different biological and cognitive processes involved in spatial navigation.

L: Therefore, while Maguire’s research shows that the brain can change in response to frequent exposure to particular tasks, some psychologists suggest that a holistic approach to understanding human behaviour may be more appropriate.

Question 20

Evaluation for plasticity: Application

Answer 20

P: A final strength of research into plasticity and functional recovery is the application to neurorehabilitation.

E: Understanding the processes of plasticity and functional recovery led to the development of neuro-rehabilitation. It uses motor therapy and electrical stimulation of the brain to counter the negative effects and deficits in motor and cognitive functions following accidents, injuries and/or strokes.

L: It demonstrates a positive real world application of research in this area to help improve cognitive functions of people suffering brain

Question 21

Evaluation for plasticity: Support from animal research?

Answer 21

P: Early evidence of neuroplasticity and functional recovery was derived from animal studies.

E: A study by Hubel & Wiesel (1963) involved sewing one eye of a kitten shut and analysing the brain’s cortical (outer layer of the cerebrum) responses.

L: It was found that the area of the visual cortex associated with the shut eye was not idle (as had been predicted) but continued to process information from the open eye – compensation of unaffected brain

Question 22

Schneider et al. (2014) — Education & Functional Recovery.

Answer 22

Studied 769 patients with head injuries.

Found that patients with more years of education were more likely to achieve disability-free recovery.

Suggests cognitive reserve plays a big role in functional recovery.

Question 23

Outline the difference in function between Broca’s area and Wernicke’s area

Answer 23

Broca’s area

In the left frontal lobe

Responsible for speech production — forming words and putting sentences together

Wernicke’s area

In the left temporal lobe

Responsible for language comprehension — understanding spoken and written language