Plasticity+ functional recovery of brain after trauma

Question 1

Definition of Brain Plasticity

Answer 1

• Brain Plasticity: The brain’s ability to change and adapt in response to experience, learning, or injury.
• Key Concept: Neural pathways and synapses can strengthen, weaken, or reorganise depending on the individual’s experience or after brain damage.

Question 2

Types of Brain Plasticity

Answer 2

1. Developmental Plasticity: Changes in the brain’s structure during growth and development, primarily in childhood.
2. Adaptive Plasticity: The brain’s ability to reorganise itself in response to damage or new learning in adulthood.

Question 3

Synaptic Pruning

Answer 3

• Synaptic Pruning: A process where extra synaptic connections that are no longer needed are eliminated, while frequently used ones are strengthened.
• Key Concept: Pruning occurs during childhood and adolescence and helps make neural networks more efficient.

Question 4

Plasticity and Learning

Answer 4

• Learning and Plasticity: Repeated exposure to new experiences or learning a skill can strengthen and reorganise neural pathways.
  o Example: Learning a new language or musical instrument increases synaptic connections in related brain areas.
• Evidence: Research on London taxi drivers shows that their hippocampus, involved in spatial navigation, is larger due to their extensive training and navigation skills (Maguire et al., 2000).

Question 5

Functional Recovery After Trauma

Answer 5

• Functional Recovery: The brain’s ability to recover from damage by reorganising or redistributing functions to undamaged areas.
• This occurs following trauma such as stroke, brain injury, or surgery.

Question 6

Mechanisms of Functional Recovery

Answer 6

1. Axonal Sprouting: Growth of new nerve endings to connect with undamaged neurons to form new neural pathways.
2. Recruitment of Homologous Areas: The brain enlists similar areas on the opposite hemisphere to perform specific tasks.
3. Neural Unmasking: Dormant synapses, not usually used, become active to compensate for lost functions.
4. Stem Cells: Emerging evidence suggests that stem cells could replace dead or damaged cells or help form new connections.

Question 7

Research Supporting Plasticity and Functional Recovery

Answer 7

• Maguire et al. (2000): Studied the brains of London taxi drivers using MRI scans. Found that the longer they had been on the job, the larger their posterior hippocampus (involved in spatial navigation), showing the effect of environmental demands on brain structure.
• Kuhn et al. (2014): Found that playing video games caused increases in grey matter in brain areas associated with memory, spatial awareness, and strategic planning.
• Draganski et al. (2006): Showed increased grey matter in the hippocampus of medical students studying for exams, demonstrating that learning can affect brain structure.

Question 8

Evaluation of Brain Plasticity

Answer 8

• Strengths:
  1. Practical Applications: Insights into plasticity have led to rehabilitation techniques to aid recovery after brain trauma, such as cognitive therapy and physical rehabilitation.
  2. Empirical Evidence: Research such as Maguire’s taxi driver study offers strong support for the concept of plasticity.
• Limitations:
  1. Individual Differences: The degree of plasticity and recovery varies greatly between individuals, depending on factors like age, severity of trauma, and education.
  2. Negative Plasticity: Maladaptive plasticity can occur, such as the development of phantom limb syndrome, where individuals feel sensations in amputated limbs due to reorganisation in the somatosensory cortex.

Question 9

Factors Affecting Functional Recovery

Answer 9

1. Age: Younger brains are more plastic, so recovery from brain injury is often faster and more complete in younger individuals.
2. Education: Studies suggest that people with higher levels of education recover better, possibly due to a more cognitively active lifestyle.
3. Time Since Trauma: The sooner rehabilitation starts, the better the chances of recovery.
4. Perseverance and Effort: Greater engagement with rehabilitation techniques leads to better recovery.

Question 10

Practical Applications of Plasticity and Recovery

Answer 10

• Neurorehabilitation: Therapies aimed at helping the brain recover function post-trauma.
  o Examples:
   Physical therapy: Encourages movement and retraining of motor skills.
   Cognitive therapy: Helps regain memory and problem-solving skills.
• Stem Cell Therapy: Research into using stem cells to treat brain injuries is ongoing. The idea is to replace damaged cells or promote the growth of new ones.

Question 11

Key Exam Points for Plasticity and Functional Recovery

Answer 11

• Key Terms: Be able to define brain plasticity, synaptic pruning, axonal sprouting, and functional recovery.
• Research Studies: Understand the findings and significance of key studies such as Maguire et al., Kuhn et al., and Draganski et al.
• Evaluation: Be ready to discuss the strengths and limitations of plasticity, such as its practical applications and individual differences in recovery.
• Mechanisms: Know the key mechanisms of recovery like axonal sprouting, neural unmasking, and stem cells.