Brain plasticity Flashcards
Define plasticity
The brain adapts in both its function and structure as a result of a change in the environment
These changes could be due to damage or to meet cognitive demands
cognitive demands of learning new skills
What are the 4 reasons for plasticity
- Learning new skills
- A result of developmental changes
- Response to direct trauma to areas of the brain
- Response to indirect effects of damage such as swelling or bleeding from a stroke
What is functional recovery/reorganisation
The functions that were performed by areas of the brain that are lost (neuronal cell death) or damaged are performed by undamaged areas
What is synaptic pruning
Synapses that are used frequently become stronger over time however unused synpatic connections are lost
What is axonal sprouting
Existing neurons gorwing new axons to connect to adjacent neurons
What is another response to the loss of axons ina path way
Denervation supersentivity- To compensate for the loss of axons in a pathway the remaining axons become more sensitive which can cause side effetcs like pain
What are 3 examples of factors affecting functional recovery
- Age: children have the best ability to recover
- Gender: Women are more likely to recover from brain damage
- Rehabilitive therapy: Focused effort results in impprovement
What is constraint induced therapy
Stopping paitents from using copying strategies (like body languagr for comminication) making them improve via functional reorganisation
Maguire et al 2000
- Structural MRI brain scans of 16 male taxi drivers were compared to the brain scans of 16 matched (age,gender) non taxi driver controls
- The posterior hippocampi in the london taxi drivers were found to be significantly larger than the controls. Also the size of the posterior hippocampi was positively correlated with the amount of time working as a taxi driver
- This suggests the physical structure of the brainb is plastic,Able to reconfigure itself to better adapt to psychiology demands, in this case to i8mprove memory formation
Danelli et al 2013
- Case study of 14 Year old EB. at the age of 2 and a half EB had a hemispherectomy of the left side of his brain te remove a tumour.This removed the language centres of Brocas and wernickes areas
- Immediately after surgery EB had lost all language ability (aphasia) howver after two years of recovery EB had recovered his language ability but he did have some dyslexia like symptoms.
- Researchers noted FMRI scna showed the right hemisphere followed a left like blueprint for language
- This research suggests that the brain can adapt and reocver after signiifcatnt damahe especially if that truama occurs early in life
Hemispherectomy- removal of one side of the brain
Evaluations Pros:
- Practical applications: research on brain plasticity and function reocvery has practical benefeits it has beem useful in rehabilitvw therapy, helping people return to their lives and productive work ultamibelty benefitinbg the wider economy
- Research on indiivuals reocvering lost function can help psychilogists understand mor about the functions of regions of teh brain that wqere initially damaged
Evaluation Cons:
- Indivudal differneces in recover: A metaanalysis by Mathias (2015) demonstrated IQ and educational background are positvely correlated with better outcomes after traumatic brain injury suggesting some individuals have a greater coginitive reserve, helping in reocvery
- Negative plasticity: The brains ability to revive itself can sometimes be maladaptive. Pronlonged durg use has been shown to resulyt in poorer cognitive functions as well as increased risk of demnetial later in life . Also 60-80% of amputees develop Phantiom limb syndrome- the contunued experince of sensations in the amputated limb. these sensations are unpleasent and painful
