 On the other hand, lesser amounts of white matter are found in the left inferior arcuate fasciculus connecting the temporal and frontal areas in stuttering adults.Results have shown that there is less coordination between the speech motor and planning regions in the brain's left hemisphere of men and women who stutter, when compared to a non-stuttering control group.Anatomical connectivity of the speech motor and planning regions is less vigorous in adults who stutter, especially women.