Neat. After reading that I had as many neurons in my gut as a cat has in its head,<p>> a network of neurons that line your stomach and your gut. Surprisingly, there are over 100 million of these cells in your gut, as many as there are in the head of a cat.<p>I had to look up how many neurons are in the human brain - about 100 billion:<p><a href="http://en.wikipedia.org/wiki/Neuron#Neurons_in_the_brain" rel="nofollow">http://en.wikipedia.org/wiki/Neuron#Neurons_in_the_brain</a>