Monday, November 21, 2011
Mind the gap
A recent cover of the journal Science. What is it?
A "conceptual illustration of information, in the form of electrical impulses, flowing through neuronal processes in the brain."
An estimated 100 billion neurons in the human brain. Each neuron reaching out with spidery arms to touch thousands of others. Or almost touch, at connections called synapses. Each synapse in any one of about ten levels of excitation.
Something like 100 trillion synapses, spidery fingertips almost touching.
I like to think of those synaptic gaps as physical embodiments of the famous gap between the finger of Adam and the finger of God in Michelangelo's Sistine Chapel painting. The fingertips don't quite touch. But one can feel -- sense -- the energy flowing across the gap.
One hundred trillion synapses, in different levels of excitation. That is me, that spider web, that softball-sized glob of spider-web meat. One hundred billion neurons, and an equal number of glial cells , physically supporting the neurons, protecting them from pathogens, feeding them with nutrients and oxygen. My conscious life. My self-awareness. My dreams. My lifetime of memories.
For no other organ of the human body is the relationship between structure and function so poorly understood as for the brain. Finding out how those flickering neurons give rise to a conscious self will be the premier problem of biology in the 21st century.
For the time being, I'll continue to think of those 100 trillion synapses as 100 trillion almost-touching fingertips of God and Adam, where my soma plays roles both human and divine -- the spark of selfhood spontaneously arising from the enormous complexity of the organ.