Plasticity and Functional recovery of the brain after trauma Flashcards
AO1: Plasticity
Plasticity is the brain’s ability to change and adapt its structures and processes as a consequence of experience and new learning. During infancy the brain experiences a rapid growth in the number of synaptic connections but as we age, connections that are not used regularly are deleted and ones that are used regularly are strengthened – this is called synaptic pruning.
Functional recovery is a type of plasticity and refers to recovery of abilities and mental processes (such as movement or language) that have been affected as a result of brain damage or disease. The brain is able to rewire itself by forming new synaptic connections close to the damaged area of the brain . Secondary neural pathways that would not typically be used to carry out certain functions are activated to enable functioning to continue, often in the same way as before. This process creates a number of structural changes in the brain.
Axonal sprouting is when undamaged axons grow new nerve endings which reconnect the neurons, where connections had been damaged.
Recruitment of homologous areas is when areas from the opposite side of the brain take over the function of the damaged area of the brain e.g. if the Broca’s was damaged in the LH, the right sided equivalent would carry out its functions.
What are the five factors affecting recovery? (AO2)
Perseverance
Age
Gener
Education
Stress and alcohol
What are the evaluations for plasticity? (4)
1) RTS EB
2) Discussion - lacks population validity
3) RTS Maguire - taxi drivers
4) Practical applications - Neurorehabilitation
AO3: RTS EB
Research to support plasticity and functional recovery of the brain comes from a case study on a patient named EB. EB suffered from brain damage that resulted in the removal of his left hemisphere and therefore his language centres. Despite this, after some time EB managed to regain some of his language ability which would not be possible if the brain was completely lateralised. This suggests that EB’s brain has experienced recruitment of homologous areas and demonstrates the brain can adapt to produce language even when the left hemisphere is not present or functioning, therefore supporting the idea of plasticity and functional recovery. Therefore, increasing the validity of research into plasticity and functional recovery.
Discussion - EB’s research
However, this research lacks population validity as the case study only involves one participant, EB who had severe brain damage. This is an issue as it may have caused unique changes in the brain that may have influenced the plasticity and functional recovery of the brain. This limits how well the research can be generalised to the wider population as different genders or age groups may experience different levels of plasticity in the brain. Thus, this lowers the external validity of the research into plasticity and functional recovery.
AO3: Taxi
Research to support plasticity of the brain comes from Maguire et al who studied the brains of London taxi drivers. It was found that those who had been taxi drivers for a long time had a greater volume of grey matter in the area responsible for spatial and navigational skills (posterior hippocampus) in comparison to those who had only been a taxi driver for a short time. This supports plasticity because it suggests that the change in the structure of the brain was altered by their experience and greater knowledge of the roads. Therefore, increasing the validity of research into plasticity and functional recovery.
AO3: Practical applications
A strength of the research investigating plasticity and functional recovery is that it has practical applications. This is because the principles of the theory that it is possible for an individual’s brain to recover from damage through recruitment of homologous areas has led to the development of neurorehabilitation. This where the patient practises repeatedly using the affected side of their body e.g., an arm, whilst restraining the unaffected arm, so they can regain functioning which can improve quality of life. Therefore, this is as an important area of applied psychology as it helps to treat people in the real world.
