Brain Plasticity�Module 1.4-8

The brain’s ability to modify itself after damage

2 Types of Plasticity

1. Structural Plasticity – Actual changing of the neuron or actually growing new neurons.
• Neurogenesis – producing new neurons – rare in adult humans
• Stem Cells could be used to develop into a neural cell that needs to be replaced.
2. Functional Plasticity – When an area of the brain takes up a new function to replace a damaged area of the brain.

Examples of Plasticity

• If a body part is amputated, the surrounding neurons in the somatosensory cortex rewire themselves to other areas in the body.

​

​

​

​

​

• A 5-year old boy who had severe seizures in his left hemisphere required the removal of the entire left hemisphere. What was the result?

• Example: The hand is near the face on the sensory cortex thus when stroking the face of someone whose hand was amputated, the person felt the sensation not only on their face but also on their nonexistent “phantom” fingers.

​

• While he is paralyzed on his right side he grew up to have above average intelligence, completed college and grad school and is now a business executive.

More Examples of Plasticity

• A laser beam damages a spot in a cat’s eye, the brain area that received input from that spot will soon begin responding to stimulation from nearby areas in the cat’s eye.
• Newborn ferrets had the optic nerve of their brains rewired to take visual information into their auditory cortex. Result? It could see light in its auditory cortex.
• If a blind person uses one finger to read Braille, the area of the brain dedicated to that finger expands.
• The sense of touch invades the part of the brain normally used for sight in blind people.

• Daniel Kish uses Echolocation to maneuver through the world. His occipital lobe has wired to enhance his hearing. (video 3 min)

​

More on Phantom Limbs�

• Mirror Therapy to help with Phantom limb pain. See video HERE for explanation (4 min).
• Create a Fake Phantom Limb Demo

​

Brain Plasticity�Can the brain rewire itself if you lose half your brain?�5 minute clip� Click below to view video

​

​

​

​

​

See video from class on hemispherectomy

Can a person’s environment affect their brain development?� YES!�

An enriched environment = more neural connections in the brain.

• Exercise will cause more blood vessels to grow
• Learning Activity will cause more dendrites and axon terminals and thus more neural connections.

​

�London Cab Drivers �rewire their brain