RESEARCH ARTICLE Multimodal MRI suggests that male homosexuality may be linked to cerebral midline structures 1,2 1 Amirhossein Manzouri , Ivanka SavicID * 1 Department of Women's and Children's Health, and Neurology Clinic, Karolinska Institute and Hospital, Stockholm, Sweden, 2 Department of Psychology, Stockholm University, Stockholm, Sweden *
[email protected] a1111111111 a1111111111 a1111111111 Abstract a1111111111 a1111111111 The neurobiology of sexual preference is often discussed in terms of cerebral sex dimor- phism. Yet, our knowledge about possible cerebral differences between homosexual men (HoM), heterosexual men (HeM) and heterosexual women (HeW) are extremely limited. In the present MRI study, we addressed this issue investigating measures of cerebral anatomy OPEN ACCESS and function, which were previously reported to show sex difference. Specifically, we asked Citation: Manzouri A, Savic I (2018) Multimodal whether there were any signs of sex atypical cerebral dimorphism among HoM, if these MRI suggests that male homosexuality may be were widely distributed (providing substrate for more general `female' behavioral character- linked to cerebral midline structures. PLoS ONE 13 istics among HoM), or restricted to networks involved in self-referential sexual arousal. Cor- (10): e0203189. https://doi.org/10.1371/journal. pone.0203189 tical thickness (Cth), surface area (SA), subcortical structural volumes, and resting state functional connectivity were compared between 30 (HoM), 35 (HeM) and 38 (HeW). HoM Editor: Alexander Annala, City of Hope, UNITED STATES displayed a significantly thicker anterior cingulate cortex (ACC), precuneus, and the left occipito-temporal cortex compared to both control groups. These differences seemed coor- Received: June 3, 2017 dinated, since HoM also displayed stronger cortico-cortical covariations between these Accepted: August 1, 2018 regions.