How Flexible is the Brains Circuitry? :: Biology Essays Research Papers

How Flexible is the Brain's Circuitry? The brain is a complicated organ, containing an estimated 100 billion neurons and around 1,000 to 10,000 synapses for each of those neurons (1). This organ has the great responsibility of not only controlling and regulating the functions of the body but also sensing and perceiving the world around it. In humans, it is what we believe makes us the highly adaptive and intelligent organisms that we are, as well as give us our individuality. But with so many parts and connections to it, what happens when the brain's delicate circuitry is disrupted? We've all heard of brain damage, and its horrible results, whether is a news report on TV or science books. It seems that with trauma, disruption of blood supply, and disease; neurons and their connections could be destroyed and the organism's behavior exceedingly affected. Yet I've read about how people have overcome tremendous damage to their brains and gone on to function with very minimal handicaps. In elementary biology, we are all taught that cells in our body go through systems that replaces old, worn out cells with new cells. Most cell types go through programmed cell death, or PCD, but there was always an exception in the neuron; very early in mammalian development, neurons stop growing (4). PCD would be disastrous, as the depleted neurons would never be replaced. Since we need all our neurons and their connections to function, how do individuals with damage to both these neurons and connections survive, much less functioning within any definition of normality? After all, remove a few chips from a computer's motherboard and you won't have functioning computer. Yet there are children living their lives with only half their brains intact One of the most memorable case studies I read about in high school psychology was the procedure of removing large portions, sometime half the brain, to treat young children with epileptic seizures. This procedure, called hemi-spherectomy, was developed in the 1920's but rarely performed due to complications (8). With the advances in medicine today, it has become a more common practice in treatment severe epilepsy. At first, though the procedure was expected to stop the seizures, doctors did not expect these children to ever function normally. After all, with so much of the brain missing, it is hard to expect much of the mental functions of these children. Surprisingly, these children often retained much of their personality, memories and sense humor (8), awing their doctors with the flexibility of the brains to adjust after such invasive surgery.