Plasticity & Functional Recovery

• What is plasticity in terms of the brain?

  Plasticity is when 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 the cognitive demands of learning new skills.
• Give some reasons for plasticity in the brain.

  • Learning new skills.
  • A result of developmental changes.
  • A response to direct physical trauma to an area of the brain.
  • A response to indirect effects of damage like brain swelling or bleeding.
• What is functional reorganisation?

  Functional reorganisation is when, after brain damage, undamaged areas of the brain assist in functions that were performed by areas of the brain that are damaged.
• Why can infants recover from brain damage more easily than adults?

  Infants can recover from brain damage more easily than adults because their brains are undergoing rapid growth and are highly adaptable. During infancy, the brain forms synaptic connections at an extraordinary rate, peaking at about 15,000 synapses per neuron around ages 2-3, which is roughly twice the number found in adult brains. This abundance of synaptic connections provides a greater capacity for the brain to reorganize and compensate for damage.
• Synapses that are frequently used in the brain become stronger over time, however, unused synaptic connections are lost - the process of removing unused connections is called synaptic pruning, this process makes the brain a more efficient communication system over time.
• Functional recovery is a form of plasticity
• What is functional recovery?

  Following an injury to the brain or other forms of trauma such as a stroke, unaffected areas of the brain are often able to adapt and compensate for those areas that are damaged, taking over the functions of damaged areas.
• Functional recovery can be spontaneous (occurs quickly after trauma) and then slow down after weeks/months. Recovery is more likely to occur when the brain is still maturing, so age is a factor, as is gender.
• What is axonal sprouting?

  Axonal sprouting can be used to connect with undamaged nerve cells to provide new neuronal pathways when damage occurs. This neural regeneration is the growth of new neuronal cells.
• What is denervation supersensitivity?

  Denervation supersensitivity is the process of making the remaining axons after brain damage more sensitive which makes them more likely to fire.
• What is a side effect of denervation supersensitivity?

  Due to axons being more sensitive side effects such as pain may occur.
• How do homologous areas on the opposite side of the brain help with functional recovery?

  Homologous areas on the opposite side of the brain will take on tasks usually performed by the opposite side of the brain after damage.  An example of this would be if Broca’s area was damaged on the left side of the brain, the right-side equivalent would carry out its functions. After a period of time, functionality may then shift back to the left side.
• Age is a factor in functional recovery as children have the best ability to recover from brain damage compared to young adults.
• Gender is a factor in functional recovery as women are more able to recover from brain damage than men.
• Rehabilitative therapy is a factor in functional recovery as this focused effort to treat the brain damage have positive results.
• What is constraint-induced therapy?

  Constraint-induced therapy stops the patients from using coping strategies, like body language for communication or using undamaged limbs for tasks, instead making them improve via functional reorganisation.