Traditional lap pools are about 10 feet wide, though widths between 8 and 10 feet are common. (In competition pools, swim lanes are 2.5 meters wide, or about 8.2 feet.) You don't want to go too narrow with a lap pool.
The number of neurons in the brain varies dramatically from species to species. One estimate (published in 1988) puts the human brain at about 100 billion (10 11) neurons and 100 trillion (10 14) synapses.
What are neurons? What is the brain made of? The bulk of the brain is made up of structural cells termed glial cells and astrocytes. Lying in amongst these cells are neurons, specialized cells that conduct electrical impulses along their processes. It has been estimated that the average human brain contains about 100 billion neurons and, on average, each neuron is connected to 1000 other neurons. This results in the generation of vast and complex neural networks that are the mainstay of the brain's processing capabilities.