Just a link.
Since the mid-nineteenth century, most researchers have assumed that left-handers are right-brained in terms of both motor and language function. That is, they have believed that given the contralateral nature of brain/side function—that the right side of the body is controlled by the left cerebral hemisphere and vice versa—left-handers would be right-brained for language. This is not so. Imaging studies reveal that only 18 percent of left-handers are localized to the right hemisphere for language and speech, while 12 percent are bilateral, having language in both hemispheres. Thus, for 70 percent, language and speech are located in the left hemisphere. Complicating matters, 5 percent of right-handers also have right-hemisphere language dominance, with 95 percent being left-hemisphere dominant. - See more at: http://www.emory.edu/ACAD_EXCHANGE/issues/2012/spring/stories/kushner/index.html#sthash.Bns7Rbbo.dpuf