Let me count the beans…
We have about 100 billion neurons (nerve cells) in our brain, ok give or take a billion or two. Each neuron has an average of maybe 1000 synapses – connections between neurons without which the brain is as good as dead. These connections make it possible for one part of the brain to talk to another (Oh yes, connections, connections!). So we have 100 trillion connections in our brain (100 billion x 1000).
Now then, how do our everyday body cells (skin, muscle, liver, gland cells etc) communicate with each other, and with the neurons? Do they make connections too? They’d better or we are truly dead – or at least insensate.
For one, many nerves (strings of neurons connected by synapses) connect the brain to the body via the spinal cord, and go to every part of our body: muscles, lungs, heart, kidneys, skin etc. This is one of our brain-body connects – the nervous system. It contains nerves that carry messages from the brain, and also those that relay messages from the body. But this is not the only system!
The other system – the peptide-receptor network, also makes connections throughout the body (which includes the brain). This system reaches every single cell, not just the nerve cells. Its messenger molecules are the peptides (very small fragments of protein molecules) which are present in the body and brain fluids that bathe every single cell in the entire body. If we call the nervous system highways, the peptide-receptor network would be footpaths, which can form anywhere, spontaneously, that crisscross our body.
Now let’s see.
By sheer numbers, the peptide-receptor network of communication trumps the nervous system of synaptic connections, hands down. Every cell in our body has millions of receptor sites for connections on its surface, receiving those travelling peptide messengers. Let’s say conservatively there are one million receptors per cell, multiply that by the number of cells in our body, oh maybe 50,000 billion or so (for someone small, like me). Now we have 50 million trillion connections.
So there you have it. The brain has 100 trillion connects – but the body wins with 50 million-trillion connections (that’s 5 with 19 zeros).
That is, for every synaptic connection in the brain, the body has 500,000 connections in the peptide-receptor network. The body is smarter. Or potentially so.
If only our brain will allow our body cells to speak up!
Note: for a discussion of the discovery of the peptide-receptor network, read my essay Information = Knowledge?