Although much new information was gathered concerning the correct anatomy of the brain, the work of Vesalius did not have a direct bearing on knowledge of brain function. The fundamental idea of Phrenology was that complex mental faculties, such as Cautiousness, Combativeness and Agreeableness, and simpler functions, such as Memory, Calculation Ability and Color Perception, were localized in discreet areas of the brain. Phrenology correlated the mental faculties described by philosophers such as Thomas Reid with the development of specific brain areas. The development of these brain areas, called cerebral organs, resulted in skull prominences. These bumps could be analyzed and a Phrenology practitioner could determine the subject's personality and intelligence from analysis of the skull, called cranioscopy.
Phrenology represents the beginning of the strong localizationist doctrine that is present today.
This controversy was not resolved until the studies of 19th Century neurologists, expecially Wernicke. The patient could accurately comprehend language. Broca then used this case and a number of others to prove conclusively that the expression of language was localized to the left frontal lobe. If you look carefully at the brain, you can detect a soft, fluid-filled area in the frontal lobe. Several years after Broca presented his cases of frontal lobe lesions, Wernicke presented cases in which patients had lesions of the posterior parts of the left hemisphere and had trouble comprehending language.