Plasticity & Functional Recovery of the Brain After Trauma

• What is brain plasticity?

  The brain's ability to change and adapt
• What happens to synaptic connections during infancy?

  They rapidly grow in number
• How many synaptic connections does the brain reach by age 2-3?

  About 15,000 connections
• What is synaptic pruning?

  Deletion of unused connections and strengthening of used ones
• What was the aim of Maguire et al (2000)?

  • Examine structural changes in the brain
  • Focus on individuals with spatial navigation experience
• What was the procedure in Maguire et al (2000)?

  • Studied brains of London taxi drivers
  • Compared with a matched control group of non-taxi drivers
• What did Maguire et al (2000) find in taxi drivers' brains?

  More grey matter in the posterior hippocampus
• What is the role of the hippocampus?

  Development of spatial and navigational skills
• How does the learning experience of taxi drivers affect their brains?

  It alters the structure of their brains
• How does age affect brain plasticity?

  • Plasticity generally reduces with age
  • Bezzola et al (2012) showed plasticity can occur in older adults
• What did Bezzola et al (2012) demonstrate about golf training?

  It produced neural changes in older participants
• What did fMRI reveal in Bezzola et al (2012) study?

  Increased motor cortex activity in novice golfers
• What is negative plasticity?

  Brain adaptation leading to poorer cognitive functioning
• What did Medina et al (2007) find about prolonged drug use?

  It leads to poorer cognitive functioning
• What percentage of amputees develop Phantom Limb Syndrome?

  60 - 80%
• What causes Phantom Limb Syndrome?

  Cortical reorganisation in the somatosensory cortex
• What is functional recovery in the brain?

  • Redistribution of functions after brain damage
  • Unaffected areas adapt to compensate for damage
• How quickly can functional recovery occur after trauma?

  Quickly, then slows down over time
• What happens to synaptic connections after brain damage?

  New connections form near the damage
• What are the processes supporting structural changes in the brain?

  • Axonal Sprouting
  • Denervation Supersensitivity
  • Recruitment of Homologous Areas
• What is axonal sprouting?

  Growth of new nerve endings connecting undamaged cells
• What is denervation supersensitivity?

  Axons become more aroused to compensate for lost ones
• What happens when one area of the brain is damaged?

  Functionality may shift to the opposite side
• What is the real-world application of understanding brain plasticity?

  • Contributes to neurorehabilitation
  • Encourages new therapies like constraint-induced movement therapy
• What did Schneider et al (2014) reveal about education and brain injury recovery?

  More education leads to better recovery chances
• What percentage of individuals with over 16 years of education achieved a disability-free recovery?

  40%
• What percentage of individuals with less than 12 years of education achieved a disability-free recovery?

  10%
• What does a lack of sufficient education imply for recovery from brain damage?

  Less likely to achieve full recovery
• What is a limitation for Plasticity of the Brain?

  • Negative Plasticity
  • Medina et al (2007) has shown that the brain’s adaptation to prolonged drug use leads to poorer cognitive functioning in later life, as well as increased risk of dementia
  • Also, 60 - 80% of amputees have been known to develop Phantom Limb Syndrome, which is thought to be due to cortical reorganisation in the somatosensory cortex
  • This suggests that the brain’s ability to adapt to damage is not always beneficial
• What is a strength for Plasticity of the Brain?

  • Age & Plasticity
  • In general, plasticity reduces with age, however, Bezzola et al (2012) demonstrated how 40 hours of golf training produced changes in the neural representations of movement in participants aged 40 - 60
  • Using fMRI, the researchers observed increased motor cortex activity in the novice golfers compared to a control group, suggesting more efficient neural representations after training
  • This shows that neural plasticity can continue throughout the lifespan
• What is a strength for Functional Recovery of the Brain After Trauma?

  • Real World Application
  • Understanding the processes involved in plasticity has contributed to the field of neurohabilition
  • Understanding that axonal growth is possible encourages new therapies to be tried, such as constraint-induced movement therapy
  • This shows that research into functional recovery is useful as it helps medical professionals know when interventions need to be made
• What is a limitation for Functional Recovery of the Brain After Trauma?

  • Cognitive Reserve
  • Schneider et al (2014) revealed that the more time people with a brain injury spent in education, the greater their chances of a disability-free recovery
  • 40% of those who achieved a disability-free recovery had more than 16 years education compared to the 10% of those who had less than 12 years education
  • This would imply that people with brain damage who have an insufficient disability-free recovery are less likely to achieve a full recovery