"Richard Bergland, a neurosurgeon, asked what role the CSF and the brain's ventricular system could play in the brain's physiology. Using paper chromatography, a method that separates substances dissolved in a fluid, he observed more than 300 different peptides and amino acids in the CSF. He induced seizures in sheep, extracted CSF from the ventricles, and found these substances to substantially increase in variety and amount after seizures."