Poster B116, Sunday, March 26, 8:00 – 10:00 am, Pacific Concourse
Differences in association for surface area and thickness within functional brain networks between monozygotic and dizygotic twin pairs
Elena Molokotos1, Amy Janes2, Matthew Jerram1; 1Suffolk University, 2McLean Imaging Center
Heritability rates of cortical surface area (SA) and thickness differ regionally. Whether these patterns correspond with functional brain networks is unclear. Such a link is plausible as network activation is heritable and brain function and structure are coupled. To determine the heritability of primary resting state networks (RSNs), we evaluated the SA and thickness of the default mode network (DMN), central executive network (CEN) and salience network (SN). The Human Connectome Project collected magnetic resonance imaging data for monozygotic (MZ, n = 72) and dizygotic (DZ, n = 60) twin pairs. Following a standard freesurfer pipeline, total network SA and thickness were calculated by summing the values of individual regions known to comprise these RSNs. Pearson correlation coefficients were calculated for thickness and area of RSNs in MZ and DZ twin sets. To demonstrate a genetic influence, correlation coefficients were z-transformed and compared between MZ and DZ sets. Relative to DZ twins, MZ twins showed stronger correlations for SA of the SN (p = .002), CEN (p = .001), and DMN (p = .001) and thickness for the CEN (p = .001) but not the other networks. The heritability of network anatomy is congruent with prior work showing strong heritability of global brain structure. These findings suggest that, while SA is heritable across networks, thickness is only heritable within the CEN. It is hypothesized that SA and thickness are mediated via different genetic mechanisms and the results suggest that the CEN structure is more broadly genetically determined than other RSNs.
Topic Area: NEUROANATOMY