Also, Galaburda found the MGN to be smaller than normal symmetry. Thus, a dyslexic person takes .1 seconds to process sounds, as compared to a normal reader processing sounds in .04 seconds. As far as symmetry of the hemispheres, the majority of the neurological research for SLDs, especially RDs, has been these studies of hemisphere symmetry through the morphology of the corpus callosum and the planum temporale region. Galaburda et al.found differences in language function areas for people with SLDs, such as symmetry or reversed asymmetry of Wernicke's area and chaotic patterns of the planum temporale region. This data may correlate with Gross-Glen et al.
Reverse asymmetry is opposite the norm of the left hemisphere being larger than the right.
Heir et al. found reverse asymmetry in SLD with a wider posterior right hemisphere. In addition to this reverse asymmetry, Filipek et al. also found the right hemisphere to be wider in the posterior and narrower overall with the left hemisphere being the same as the norm. Duara et al. had the most information on the corpus callosum being more shallow in SLD with little separation. Yet, the right hemisphere was larger than the left in the midposterior angular gyrus region of the inferior parietal lobe. Also, people with RDs had a large splenum and a more narrow callosum allowed for more interhemispherical activity.