Date of Award

Summer 8-18-2022

Author's School

Graduate School of Arts and Sciences

Author's Department


Degree Name

Master of Arts (AM/MA)

Degree Type



Behavioral genetic analyses have not demonstrated robust, unique, genetic correlates of hippocampal subregion volume. The following study is the first population-based investigation of a) hippocampal longitudinal axis genetic factors b) hippocampal transverse axis genetic factors using both T1 and T2 MRI images and c) differences in the genetic components of hippocampal volume between post-adolescent adults and pre-adolescent children. Twin-based biometric analyses demonstrated that longitudinal axis subregions are associated with significant, unique, genetic variance, and that longitudinal axis subregions that are closer to one another are more genetically related than those further to one another. Although our analyses find that certain transverse axis subfields have significant, unique, sources of genetic variance, others (e.g, CA1, DG) do not exhibit significant, unique, sources of genetic variance. Lastly, we do not find any differences in univariate or multivariate sources of genetic influence between children and adults. This study is the first to demonstrate evidence of genetic differentiation of gray matter volume along the human hippocampal longitudinal axis in living humans. Given that twin-based study designs are the most statistically powered to detect aggregated genetic effects, and the fact that the following study utilizes an unprecedented sample size to study the genetic components of hippocampal volume (930 twin pairs), the following study represents the most statistically powered investigation of hippocampal genetic differentiation in living humans.


English (en)

Chair and Committee

Deanna Barch

Committee Members

Ryan Bogdan Josh Jackson