Phrenology, often called a pseudo-medicine, is a study of the physical size of a person's head (skull), especially in the various differences in particular locations of the skull, that could determine psychological attributes. It was popular from about 1800 to the early 1900's and even had whole organizations dedicated to the pseudoscience (Edinburgh Phrenological Society).

Though now debunked science, Franz Joseph Gall, who developed Phrenology, some aspects of the study are considered valid, postulated that particular locations in the brain controlled particular functions of the human anatomy and emotional mind, including reason, emotion, morality, and psychological attributes. Neuropsychology and Neuroscience has verified these findings and though some of the "maps" that Gall made concerning the brain were incorrect, Phrenology is still considered an advancement to modern Neuroscience.

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