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Nineteenth-century neurology was dominated by two opposing schools of thought. Early in the century Franz Gall claimed that the bumps on a person's head revealed personality traits, each of which was controlled by a specific region of the brain. While this pseudoscience—phrenology- enjoyed a fashionable success. Gall was ridiculed by the leading neurologist of the 1840s, M. J. P. Flourens, who argued that the brain functioned as a whole, that individual bodily functions were not dependent on separate regions of the brain, and that it was impossible to predict the specific effects of any localized form of brain damage. In 1861 the neuroanatomist Paul Broca challenged Flourens and the holistic school by demonstrating that damage to a specific region on the left side of the cerebral cortex caused severe language problems. Subsequently, the neurologist Carl Wernicke argued that the region discovered by Broca was somehow responsible for translating language formulated in the brain into the mechanical movements of the vocal cords, the tongue, and the mouth. Wernicke believed that a separate region he himself had discovered was responsible for the recognition of speech as distinct from other sounds. Clinicians soon found that such localization of brain functions explained neurological disorders in addition to language disorders. In 1884, for example, a patient with partial paralysis had a brain tumor removed in the first such operation in medical history. The neurological symptoms enabled the surgeon to locate the exact position of the tumor. Although this localization approach was largely dismissed by scientists between the 1920s and the 1950s, the research performed by the neurologist Norman Geschwind seems to have vindicated the theories of Broca and Wernicke. Beginning in 1965 Geschwind persuasively argued that in human beings, sensory information is initially processed in primary sensory areas of the brain, then relayed to neighboring regions known as association areas, where powerful associations are made between visual and auditory sensations, auditory and tactile, tactile and visual, and so forth. Damage to association areas could, according to Geschwind, explain why some brain-damaged patients can, for example, see previously familiar objects without recognizing them, but, upon touching the same objects, name them without difficulty. : Reading Comprehension (RC)