Evolution Channel Banner
Back Home
We have entered into a Golden Age of extraordinary discovery in uncovering the mysteries of the most mysterious, complex object in the universe -- the electric human brain. Scientists have uncovered more information about the human brain in the past 15 years, than in all centuries combined.

Most people aren't consciously aware of the incredible capacity of their own brains. A human brain has more cells then the known universe has stars! As astronomers use high power telescopes to peer out into new worlds, so do neuroscientists peer into the neuron charged electric human brain, using the latest technology available. Yet, not even the technology we possess today meets the demands the most complex object in the universe poses in order for us to explore it to its fullest capacity.

Neural activity animation

Brain Scans show neural activity

For instance, we now know that more connections among the brain's estimated hundred billion neurons mean a better functioning brain. It is understanding how this electrochemical communication process takes place in our brains that can lead to innovative products and methods to enhance our brain's development.

For instance, we now know that fostering the growth of dendrites, increases the mass within the brain. We have also most recently learned the important role neurotransmitters play in good nutritional health.

Functioning much like a uniquely designed electric conduit, the brain actually encodes stimuli from the body as nerve impulses. When the electrical impulses reach the brain, they trigger the release of messenger chemicals, such as glutamate, which in turn induce electrical impulses as they travel from one neuron to another.

How Neuron's Communicate with Each Other

A single neuron connects to thousands of other neurons through points of microscopic gaps separating them, known as synapses. You can think of synapses as a freeway system in which chemical messengers known as neurotransmitters, travel between neurons. While there are about 100 different neurotransmitters, each neuron releases only one or a few different types. After its release, a neurotransmitter crosses the synapse and activates a receptor protein in the outer membrane of the receiving neuron.

This awesome network of neurons underlies our perception of the world. These connections come from inherited growth patterns and in response to outer stimuli, including internal stimuli like imagined sensations. Thus, we now know imagination can play an important role in developing a healthy brain as well.

Neurons & Evolution

Only until recently, neurons were believed to be programmed by genes to perform specific functions in the brain. Recent studies have strongly supported a new theory called Neuronal Plasticity that claims neurons are able to travel great distances from their mother nerve cells, and function based on the surrounding signals given by other neurons. In other words, they are very adaptable, and are not programmed by DNA for specific functions. For example, a paw of a mammal could turn into a wing, but the neurons that interpret sensory signals from the wing, would not need to be reprogrammed to manage the change in the body plan. Neuronal plasticity is a revolutionary discovery as it suggests that this degree of flexibility in the brain could lend itself to further evolution of consciousness, among other things.

Information Derived from:

Quiet Miracles of the Brain, Joel L. Swerdlow,
National Geographic Magazine, (June, 1995)

Neocortical Circuits and their Plasticity, Karel Svaboda, Ph.D.
Cold Spring Harbor Laboratory, www.cshl.org

A Brain Cell Surprise: Genes Don't Set Function,
Natalie Angier, January, 1992
The Science Times Book of the Brain,
The New York Times, Edited by Nicholas Wade, 1998