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Related Services Neurology and Neurosurgery. Previous Next. Show me more He presented the case before groups of intrigued scientists in Paris, and for some it was the evidence that swayed them to favor a more localizationist approach to the brain. Broca was considered a respectable and cautious scientistnot one who jumped to conclusions without an adequate amount of evidence.
Thus, the fact that he had come to believe that speech might be localized to the frontal lobes was influential. Not being completely convinced by only one case, however, Broca continued to look for other cases involving frontal lobe damage and speech deficits after Leborgne. Within just a couple of years, he had identified eight cases. What was perhaps most shocking to Broca was thatin every casethe damage was not only in a similar location in the frontal lobe, but it was also always on the left side.
The idea that the two cerebral hemispheres were different in some way was relatively unheard of at this point in time, but the clinical evidence would soon have Broca arguing for that hypothesis along with the localization of speech. The region Broca had discovered would first be known as Broca's convolution , then Broca's centre , and thenby the early s Broca's area.
In addition to becoming recognized as an important part of the brain for language production, Broca's area would be a critical piece of evidence in the debate over localization of function. Although it would not on its own end the localization debate, it helped to convince many that at least some functions are assigned to relatively circumscribed areas of the brain. Leborgne's condition became known as Broca's aphasia also known as expressive aphasia.
Its main symptom is a deficit in the ability to produce language often any type of language, including both spoken and written. Thus, the primary function most often attributed to Broca's area involves language production. Not long after Broca, however, investigators realized that a behavior as complex as speech is not likely to involve only one small region of the brain.
Thus, it is now believed that Broca's area plays an important role in language production through communication with several other brain regions. The precise role of Broca's area in language production is still debated. In other words, evidence suggests that damage to Broca's area can disrupt language production, but nobody is quite sure exactly what specific language-related function is lost to cause that disruption. Some have asserted Broca's area is involved with producing motor movements that allow speech to be produced.
Others have argued that it is involved with verbal working memory, syntax, grammar, or all of the above. Editors of Encyclopaedia , January Broca area. Encyclopedia Britannica. Chaplin, T. Scaling up the simian primate cortex: A conserved pattern of expansion across brain sizes. In Evolutionary Neuroscience pp. Academic Press.
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