Plasticity and Functional Recovery Flashcards
What is plasticity?
Brain’s ability to change overtime.
Involves growth of new connections
What does the term synaptic pruning refer to?
As people age, rarely used connections are deleted and frequently used connections = are strengthened.
New neural connections are formed due t new demands on the brain.
Research into plasticity? super mario 🎮
Kühn et al 2014
Control group vs video game training group
trained 2 months —-> 30 minutes a day
Found significant increase in grey matter in cortex/cerebellum
More areas involved in spatial navigation and motor performance.
New synaptic connections in the brain.
Gaming requires many complex motor demands
Research into plasticity 🚕
Amount of grey matter in brains of 16 taxi drivers calculated using MRI scanner.
Compared to control group of 50.
Findings of 🚕 study?
Found that posterior hippocampus of taxi drivers larger than control group.
Area of brain associated with spatial navigation.
Posterior hippocampi volume —-> positively correlated with time spent as a taxi driver
What is functional recovery?
When unaffected areas of the brain able to adapt and compensate for damaged areas
Transfer of functions to undamaged areas= neural reorganisation.
What is axonal sprouting?
New nerve endings that connect to other undamaged nerve endings
grow to create new neuronal pathways.
Neuronal unmasking?
Brain able to rewire and reorganise —-> form new synaptic connections.
Wall (1977) —-> dormant synapses which are blocked in a normal brain so synapses are ineffective.
Denervation super-sensitivity
Axons which do a similar job become aroused at higher level to compensate for the ones that are lost.
Can have negative effects such as over-sensitivity.
Recruitment of homologous areas?
Specific tasks can still be performed
E.g: Broca’s area functionality may appear on undamaged side
Evaluation: Neurorehabilitation
Possibility of axonal sprouting = new therapies being tried
Practical applications.
Sponatneous recovery starts to slow down so physical therapy is needed to maintain functional improvements.
May include movement therapy and electrical stimulation of brain to counteract deficits in motor function after a stroke.
Increases chances of disability-free recovery
Evaluation: negative behavioural consequences
Prolonged drug use leads to poor cognitive function in later life as well as increased risk of dementia (Medina et al)
60-80% of amputees known to develop phantom limb syndrome —> sensation of missing a limb
Due to reorganisation in somatosensory cortex —-> Ramacharan
