Biopsych- Plasticity And Functional Recovery Flashcards
What is plasticity
Plasticity (neuroplasticity/cortical remapping) describes the brains tendency to change and adapt (functionally and physically) as a result of experience and new learning.
Infancy - brain experiences growth in number of synaptic connections.
As we age, rarely used connections are deleted and frequently used connections are strengthened (synaptic pruning).
• At any time, existing neural connections can change or new neural connections can be formed as a result of learning and experience
Explain maguire et als study
Used structural MRI scans of male London Taxi drivers to investigate the posterior hippocampus, which is part of the brain associated with the development of spatial and navigational skills. He also used MRIs on control groups for comparison.
Taxi drivers - increased grey matter in right and left hippocampus
Longer in job - more pronounced was structural difference
Clear example of plasticity in the Brain
Explain kuhns study
Investigated cortical differences in adolescence’s that play video games and those who dont
Using MRI scans, a control group was compared to a video game group, who had to play Super Mario for at least 30 minutes a day for 2 months.
significant increase in the grey matter in numerous brain areas were associated with spatial navigation, strategic planning, working memory and motor performance for video game group
Example of plasticity
Explain lazar et al study into meditation
Meditation and mindfulness may alter brain structure
Lazar et al - mri scans demonstrated how experienced meditator had thicker cortex than non meditators particularly in areas related to sensory and attention processing
Hozel - 8 week mindfulness based stress reduction course
Increase in grey matter in left hippocampus which is strongly associated with learning and memory
What is functional recovery
A form of plasticity
Following damage through trauma the brain has ability to redistribute functions usually performed by damaged areas to undamaged areas
How does functional recovery even take place
- forming new synaptic connections close to area of damage
Secondary neural pathways activated
The process of functional recovery is supported by what structural changes
Axonal sprouting: the growth of new nerve endings which connect with other undamaged nerve cells to form new neuronal pathways.
2) Reformation of blood vessels.
3) Recruitment of homologous (similar) areas on the opposite side of the brain to perform specific tasks.
Damage to Broca’s area on the left of the brain could mean that the right-side equivalent would carry out its functions temporarily
What kind of factors affect functional recovery
How much people want to recover
• How tired people are
• How stressed people are
• How much alcohol/drugs people are having
• Age – younger individuals recover more quickly • Gender – women recover more quickly
What is a strength of plasticity
Contributed to neuro rehabilitation
Physiotherapy following illness or injury
Motor therapy , electrical stimulation help with recovery of motor and cog functions
Brain may be able to ‘fix itself’
Argued - only to a certain point to be completely successful. Other processes required
What is another strength of plasticity (animal studies)
Supporting research for neuro plasticity
Animal studies
Hubel + Welsen Sewing eye of kitten shut Analysed brains cortical response Visual cortex linked with shut eye not active Info continued to process from open eye
Unaffected areas of brain are able to compensate for damaged areas
Protection from harm, unethical
What a limitation of plasticity
Negative consequences
Plasticity - behavioural consequences
Eg 60-80
5 amputees report having phantom limb syndrome. Which are painful and unpleasant sensation of a limb still being there due to reorganisation in somatosensory cortex
Brain ability to retire itself is often unpredictable
Positive outcome not assured
What is another limitation of functional recovery (individual differences)
For example Schneider et al found that the more time brain injury patients has spent in education the greater their chance of disability free recovery
Shows that plasticity and recovery of the brain is affected by many factors so it is unpredictable and does not work in the same way in everyone
