Download Chapter 3 Week 2 Day 4

Chapter 3 Week 2 Day 4
Learning Goal Five: Describe the brain’s capacity for recovery and repair.
Brain Damage, Plasticity, and Repair
Research has been conducted on patients with brain damage to determine how
well the brain can repair itself. Recovery from brain damage depends on the
age of the individual and the extent of the brain damage.
A. The Brain’s Plasticity and Capacity for Repair
1. Most of the human brain’s plasticity is found in young children before the
age of five. For example, if a child before the age of five has brain damage
to the left hemisphere, then the right hemisphere will pick up much of the
language function. However, if damage occurs after the age of five there
may be permanent language disability.
2. Much of the brain’s ability to repair itself depends on whether the neurons
in the damaged area are completely destroyed. If the neurons were not
completed destroyed brain function may be restored over time.
3. Collateral sprouting is one way in which the brain can repair itself. The axons
on the adjacent neurons grow more branches.
4. Substitution of function is a second way the brain can repair itself. Another
area in the brain takes over the functions of the damaged area.
5. Neurogenesis is the process where new neurons are generated.
B. Brain Tissue Implants
1. Brain grafts are implants of healthy tissue that are placed into the
damaged brain.
2. The most successful cases of brain grafts are when the tissue for the
implants comes from the fetal stage.
3. The use of stem cells has been a hot debate in recent years. Stem cells are
unique because they have the ability to develop into most types of cells.
Power point: Hemispheric Specialization