Retrophrenology (r-phreno for short) is the practical application of Phrenology. Instead of merely observing the bumps on the head of the subject, retrophrenologists attempt to find the bumps that cause problems, and remove them. Likewise, bumps with positive effects are often added.
“You can go into a shop in Ankh-Morpork and order an artistic temperament with a tendency to introspection. What you actually get is hit on the head with a large hammer, but it keeps the money in circulation and gives people something to do.”
~ Sir Terry Pratchett on Retrophrenology