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.
You probably expect that a large number of neurons are required for such a complex process, but just how many neurons are there in the human brain? How Many Neurons are in the Human Brain? According to many estimates, the human brain contains around 100 billion neurons (give or take a few billion). This estimate has often been reported for many years in neuroscience and psychology textbooks and for many years was simply accepted as a relatively close approximation.