Poster A112, Saturday, March 24, 1:30–3:30 pm, Exhibit Hall C
The Effect of Degree of Handedness and Gender Differences on White Matter
Jordan Begay1, Hu Cheng Ph. D.1, Sharlene Newman Ph.D.1; 1Indiana University of Bloomington
Gender differences in the size of the corpus callosum have been reported since the early 1980’s (DeLacoste-Utamsing & Holloway, 1982; Driesen & Raz, 1995). In addition to examining the area or volume of the corpus callosum, Menzler et al., (2011) have recently used diffusion tensor imaging (DTI) to examine microstructural differences in the corpus callosum in male and female participants. They found that males had higher fractional anisotropy (FA) than females suggesting that differences in myelination account for the gender differences previously observed. However, these gender effects are not always observed with some researchers suggesting that the observed differences are due to brain size differences (Luders, Toga, & Thompson, 2014; Luders et al., 2006; Bishop & Wahlsten, 1997). In order to further explore sex differences in white matter 146 participants from the Human Connectome Project were examined (females: N=74, age=29.89±3.41; males: N=72, age=27.82±3.66). There was an equal number of left- and right-handed individuals with the handedness inventory scores for the right-handed group being 55.34± 28.33 and for the left-handed group being -58.46±30.46. Unlike in previous studies the females showed higher FA in a number of tracts including the corpus callosum and the corticospinal tract. No tracts showed increased FA for males compared to females. Further analyses are planned to investigate potential causes of these sex differences including how cognitive ability may impact these differences (Newman, 2015).
Topic Area: NEUROANATOMY