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Bakker J. Neurobiological characteristics associated with gender identity: Findings from neuroimaging studies in the Amsterdam cohort of children and adolescents experiencing gender incongruence. Horm Behav 2024; 164:105601. [PMID: 39029340 DOI: 10.1016/j.yhbeh.2024.105601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 07/05/2024] [Accepted: 07/05/2024] [Indexed: 07/21/2024]
Abstract
This review has been based on my invited lecture at the annual meeting of the Society for Behavioral Neuroendocrinology in 2023. Gender incongruence is defined as a marked and persistent incongruence between an individual's experienced gender and the sex assigned at birth. A prominent hypothesis on the etiology of gender incongruence proposes that it is related to an altered or less pronounced sexual differentiation of the brain. This hypothesis has primarily been based on postmortem studies of the hypothalamus in transgender individuals. To further address this hypothesis, a series of structural and functional neuroimaging studies were conducted in the Amsterdam cohort of children and adolescents experiencing gender incongruence. Additional research objectives were to determine whether any sex and gender differences are established before or after puberty, as well as whether gender affirming hormone treatment would affect brain development and function. We found some evidence in favor of the sexual differentiation hypothesis at the functional level, but this was less evident at the structural level. We also observed some specific transgender neural signatures, suggesting that they might present a unique brain phenotype rather than being shifted towards either end of the male-female spectrum. Our results further suggest that the years between childhood and mid-adolescence represent an important period in which puberty-related factors influence several neural characteristics, such as white matter development and functional connectivity patterns, in both a sex and gender identity specific way. These latter observations thus lead to the important question about the possible negative consequences of delaying puberty on neurodevelopment. To further address this question, larger-scale, longitudinal studies are required to increase our understanding of the possible neurodevelopmental impacts of delaying puberty in transgender youth.
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Affiliation(s)
- Julie Bakker
- GIGA Neurosciences, University of Liège, Belgium.
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Handschuh PA, Reed MB, Murgaš M, Vraka C, Kaufmann U, Nics L, Klöbl M, Ozenil M, Konadu ME, Patronas EM, Spurny-Dworak B, Hahn A, Hacker M, Spies M, Baldinger-Melich P, Kranz GS, Lanzenberger R. Effects of gender-affirming hormone therapy on gray matter density, microstructure and monoamine oxidase A levels in transgender subjects. Neuroimage 2024; 297:120716. [PMID: 38955254 DOI: 10.1016/j.neuroimage.2024.120716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 06/14/2024] [Accepted: 06/29/2024] [Indexed: 07/04/2024] Open
Abstract
MAO-A catalyzes the oxidative degradation of monoamines and is thus implicated in sex-specific neuroplastic processes that influence gray matter (GM) density (GMD) and microstructure (GMM). Given the exact monitoring of plasma hormone levels and sex steroid intake, transgender individuals undergoing gender-affirming hormone therapy (GHT) represent a valuable cohort to potentially investigate sex steroid-induced changes of GM and concomitant MAO-A density. Here, we investigated the effects of GHT over a median time period of 4.5 months on GMD and GMM as well as MAO-A distribution volume. To this end, 20 cisgender women, 11 cisgender men, 20 transgender women and 10 transgender men underwent two MRI scans in a longitudinal design. PET scans using [11C]harmine were performed before each MRI session in a subset of 35 individuals. GM changes determined by diffusion weighted imaging (DWI) metrics for GMM and voxel based morphometry (VBM) for GMD were estimated using repeated measures ANOVA. Regions showing significant changes of both GMM and GMD were used for the subsequent analysis of MAO-A density. These involved the fusiform gyrus, rolandic operculum, inferior occipital cortex, middle and anterior cingulum, bilateral insula, cerebellum and the lingual gyrus (post-hoc tests: pFWE+Bonferroni < 0.025). In terms of MAO-A distribution volume, no significant effects were found. Additionally, the sexual desire inventory (SDI) was applied to assess GHT-induced changes in sexual desire, showing an increase of SDI scores among transgender men. Changes in the GMD of the bilateral insula showed a moderate correlation to SDI scores (rho = - 0.62, pBonferroni = 0.047). The present results are indicative of a reliable influence of gender-affirming hormone therapy on 1) GMD and GMM following an interregional pattern and 2) sexual desire specifically among transgender men.
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Affiliation(s)
- P A Handschuh
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - M B Reed
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - M Murgaš
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - C Vraka
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Austria
| | - U Kaufmann
- Department of Obstetrics and Gynecology, Medical University of Vienna, Austria
| | - L Nics
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Austria
| | - M Klöbl
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - M Ozenil
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Austria
| | - M E Konadu
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - E M Patronas
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Austria
| | - B Spurny-Dworak
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - A Hahn
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - M Hacker
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Austria
| | - M Spies
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - P Baldinger-Melich
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - G S Kranz
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria; Department of Rehabilitation Sciences, Hong Kong Polytechnic University, Hong Kong, China
| | - R Lanzenberger
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria.
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Kennis M, Staicu R, Dewitte M, T'Sjoen G, Sack AT, Duecker F. Heed lessons from past studies involving transgender people: first, do no harm. Nature 2024; 629:998-1000. [PMID: 38806778 DOI: 10.1038/d41586-024-01521-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2024]
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Anger JT, Case LK, Baranowski AP, Berger A, Craft RM, Damitz LA, Gabriel R, Harrison T, Kaptein K, Lee S, Murphy AZ, Said E, Smith SA, Thomas DA, Valdés Hernández MDC, Trasvina V, Wesselmann U, Yaksh TL. Pain mechanisms in the transgender individual: a review. FRONTIERS IN PAIN RESEARCH 2024; 5:1241015. [PMID: 38601924 PMCID: PMC11004280 DOI: 10.3389/fpain.2024.1241015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 01/25/2024] [Indexed: 04/12/2024] Open
Abstract
Specific Aim Provide an overview of the literature addressing major areas pertinent to pain in transgender persons and to identify areas of primary relevance for future research. Methods A team of scholars that have previously published on different areas of related research met periodically though zoom conferencing between April 2021 and February 2023 to discuss relevant literature with the goal of providing an overview on the incidence, phenotype, and mechanisms of pain in transgender patients. Review sections were written after gathering information from systematic literature searches of published or publicly available electronic literature to be compiled for publication as part of a topical series on gender and pain in the Frontiers in Pain Research. Results While transgender individuals represent a significant and increasingly visible component of the population, many researchers and clinicians are not well informed about the diversity in gender identity, physiology, hormonal status, and gender-affirming medical procedures utilized by transgender and other gender diverse patients. Transgender and cisgender people present with many of the same medical concerns, but research and treatment of these medical needs must reflect an appreciation of how differences in sex, gender, gender-affirming medical procedures, and minoritized status impact pain. Conclusions While significant advances have occurred in our appreciation of pain, the review indicates the need to support more targeted research on treatment and prevention of pain in transgender individuals. This is particularly relevant both for gender-affirming medical interventions and related medical care. Of particular importance is the need for large long-term follow-up studies to ascertain best practices for such procedures. A multi-disciplinary approach with personalized interventions is of particular importance to move forward.
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Affiliation(s)
- Jennifer T. Anger
- Department of Urology, University of California San Diego, San Diego, CA, United States
| | - Laura K. Case
- Department of Anesthesiology, University of California San Diego, San Diego, CA, United States
| | - Andrew P. Baranowski
- Pelvic Pain Medicine and Neuromodulation, University College Hospital Foundation Trust, University College London, London, United Kingdom
| | - Ardin Berger
- Anesthesiology, Perioperative and Pain Medicine, Stanford University, Stanford, CA, United States
| | - Rebecca M. Craft
- Department of Psychology, Washington State University, Pullman, WA, United States
| | - Lyn Ann Damitz
- Division of Plastic and Reconstructive Surgery, University of North Carolina, Chapel Hill, NC, United States
| | - Rodney Gabriel
- Division of Regional Anesthesia, University of California San Diego, San Diego, CA, United States
| | - Tracy Harrison
- Department of OB/GYN & Reproductive Sciences, University of California San Diego, San Diego, CA, United States
| | - Kirsten Kaptein
- Division of Plastic Surgery, University of California San Diego, San Diego, CA, United States
| | - Sanghee Lee
- Department of Urology, University of California San Diego, San Diego, CA, United States
| | - Anne Z. Murphy
- Neuroscience Institute, Georgia State University, Atlanta, GA, United States
| | - Engy Said
- Division of Regional Anesthesia, University of California San Diego, San Diego, CA, United States
| | - Stacey Abigail Smith
- Division of Infection Disease, The Hope Clinic of Emory University, Atlanta, GA, United States
| | - David A. Thomas
- Office of Research on Women's Health, National Institutes of Health, Bethesda, MD, United States
| | - Maria del C. Valdés Hernández
- Department of Neuroimaging Sciences, Center for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Victor Trasvina
- Department of Urology, University of California San Diego, San Diego, CA, United States
| | - Ursula Wesselmann
- Departments of Anesthesiology and Perioperative Medicine/Division of Pain Medicine, Neurology and Psychology, and Consortium for Neuroengineering and Brain-Computer Interfaces, The University of Alabama at Birmingham, Birmingham, AL, United States
| | - Tony L. Yaksh
- Department of Anesthesiology, University of California San Diego, San Diego, CA, United States
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Fernández R, Zubiaurre-Elorza L, Santisteban A, Ojeda N, Collet S, Kiyar M, T'Sjoen G, Mueller SC, Guillamon A, Pásaro E. CBLL1 is hypomethylated and correlates with cortical thickness in transgender men before gender affirming hormone treatment. Sci Rep 2023; 13:21609. [PMID: 38062063 PMCID: PMC10703770 DOI: 10.1038/s41598-023-48782-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 11/30/2023] [Indexed: 12/18/2023] Open
Abstract
Gender identity refers to the consciousness of being a man, a woman or other condition. Although it is generally congruent with the sex assigned at birth, for some people it is not. If the incongruity is distressing, it is defined as gender dysphoria (GD). Here, we measured whole-genome DNA methylation by the Illumina © Infinium Human Methylation 850k array and reported its correlation with cortical thickness (CTh) in 22 transgender men (TM) experiencing GD versus 25 cisgender men (CM) and 28 cisgender women (CW). With respect to the methylation analysis, TM vs. CW showed significant differences in 35 CpGs, while 2155 CpGs were found when TM vs. CM were compared. With respect to correlation analysis, TM showed differences in methylation of CBLL1 and DLG1 genes that correlated with global and left hemisphere CTh. Both genes were hypomethylated in TM compared to the cisgender groups. Early onset TM showed a positive correlation between CBLL1 and several cortical regions in the frontal (left caudal middle frontal), temporal (right inferior temporal, left fusiform) and parietal cortices (left supramarginal and right paracentral). This is the first study relating CBLL1 methylation with CTh in transgender persons and supports a neurodevelopmental hypothesis of gender identity.
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Affiliation(s)
- Rosa Fernández
- Centro Interdisciplinar de Química E Bioloxía - CICA. Departamento de Psicología, Universidade da Coruña, Grupo DICOMOSA, Campus Elviña S/N, 15071, A Coruña, Spain.
- Instituto de Investigación Biomédica de A Coruña (INIBIC), 15071, Oza, A Coruña, Spain.
| | - Leire Zubiaurre-Elorza
- Departamento de Psicología, Facultad de Ciencias de la Salud, Universidad de Deusto, Bilbao, Spain
| | - Andrea Santisteban
- Centro Interdisciplinar de Química E Bioloxía - CICA. Departamento de Psicología, Universidade da Coruña, Grupo DICOMOSA, Campus Elviña S/N, 15071, A Coruña, Spain
| | - Natalia Ojeda
- Departamento de Psicología, Facultad de Ciencias de la Salud, Universidad de Deusto, Bilbao, Spain
| | - Sarah Collet
- Department of Endocrinology, Ghent University Hospital, 9000, Ghent, Belgium
| | - Meltem Kiyar
- Department of Experimental Clinical and Health Psychology, Ghent University, 9000, Ghent, Belgium
| | - Guy T'Sjoen
- Department of Endocrinology, Center for Sexology and Gender, Ghent University Hospital, 9000, Ghent, Belgium
| | - Sven C Mueller
- Department of Experimental Clinical and Health Psychology, Ghent University, 9000, Ghent, Belgium
| | - Antonio Guillamon
- Departamento de Psicobiología, Facultad de Psicología, Universidad Nacional de Educación a Distancia, 28040, Madrid, Spain.
| | - Eduardo Pásaro
- Centro Interdisciplinar de Química E Bioloxía - CICA. Departamento de Psicología, Universidade da Coruña, Grupo DICOMOSA, Campus Elviña S/N, 15071, A Coruña, Spain
- Instituto de Investigación Biomédica de A Coruña (INIBIC), 15071, Oza, A Coruña, Spain
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6
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Konadu ME, Reed MB, Kaufmann U, Handschuh PA, Spurny-Dworak B, Klöbl M, Schmidt C, Godber, Godbersen M, Briem E, Seiger R, Baldinger-Melich P, Kranz GS, Lanzenberger R, Spies M. Changes to hypothalamic volume and associated subunits during gender-affirming hormone therapy. J Psychiatry Neurosci 2023; 48:E369-E375. [PMID: 37751919 PMCID: PMC10521920 DOI: 10.1503/jpn.230017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 06/30/2023] [Accepted: 08/01/2023] [Indexed: 09/28/2023] Open
Abstract
BACKGROUND Among its pleiotropic properties, gender-affirming hormone therapy (GHT) affects regional brain volumes. The hypothalamus, which regulates neuroendocrine function and associated emotional and cognitive processes, is an intuitive target for probing GHT effects. We sought to assess changes to hypothalamus and hypothalamic subunit volumes after GHT, thereby honouring the region's anatomical and functional heterogeneity. METHODS Individuals with gender dysphoria and cisgender controls underwent 2 MRI measurements, with a median interval of 145 days (interquartile range [IQR] 128.25-169.75 d, mean 164.94 d) between the first and second MRI. Transgender women (TW) and transgender men (TM) underwent the first MRI before GHT and the second MRI after approximately 4.5 months of GHT, which comprised estrogen and anti-androgen therapy in TW or testosterone therapy in TM. Hypothalamic volumes were segmented using FreeSurfer, and effects of GHT were tested using repeated-measures analysis of covariance. RESULTS The final sample included 106 participants: 38 TM, 15 TW, 32 cisgender women (CW) and 21 cisgender men (CM). Our analyses revealed group × time interaction effects for total, left and right hypothalamus volume, and for several subunits (left and right inferior tubular, left superior tubular, right anterior inferior, right anterior superior, all p corr < 0.01). In TW, volumes decreased between the first and second MRI in these regions (all p corr ≤ 0.01), and the change from the first to second MRI in TW differed significantly from that in CM and CW in several subunits (p corr < 0.05). LIMITATIONS We did not address the influence of transition-related psychological and behavioural changes. CONCLUSION Our results suggest a subunit-specific effect of GHT on hypothalamus volumes in TW. This finding is in accordance with previous reports of positive and negative effects of androgens and estrogens, respectively, on cerebral volumes.
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Affiliation(s)
- Melisande E Konadu
- From the Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Kranz, Lanzenberger, Spies); the Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Lanzenberger, Spies); the Department of Obstetrics and Gynecology, Medical University of Vienna, Austria (Kaufmann); the Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Hong Kong (Kranz)
| | - Murray B Reed
- From the Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Kranz, Lanzenberger, Spies); the Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Lanzenberger, Spies); the Department of Obstetrics and Gynecology, Medical University of Vienna, Austria (Kaufmann); the Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Hong Kong (Kranz)
| | - Ulrike Kaufmann
- From the Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Kranz, Lanzenberger, Spies); the Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Lanzenberger, Spies); the Department of Obstetrics and Gynecology, Medical University of Vienna, Austria (Kaufmann); the Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Hong Kong (Kranz)
| | - Patricia A Handschuh
- From the Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Kranz, Lanzenberger, Spies); the Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Lanzenberger, Spies); the Department of Obstetrics and Gynecology, Medical University of Vienna, Austria (Kaufmann); the Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Hong Kong (Kranz)
| | - Benjamin Spurny-Dworak
- From the Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Kranz, Lanzenberger, Spies); the Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Lanzenberger, Spies); the Department of Obstetrics and Gynecology, Medical University of Vienna, Austria (Kaufmann); the Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Hong Kong (Kranz)
| | - Manfred Klöbl
- From the Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Kranz, Lanzenberger, Spies); the Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Lanzenberger, Spies); the Department of Obstetrics and Gynecology, Medical University of Vienna, Austria (Kaufmann); the Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Hong Kong (Kranz)
| | - Clemens Schmidt
- From the Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Kranz, Lanzenberger, Spies); the Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Lanzenberger, Spies); the Department of Obstetrics and Gynecology, Medical University of Vienna, Austria (Kaufmann); the Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Hong Kong (Kranz)
| | - Godber
- From the Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Kranz, Lanzenberger, Spies); the Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Lanzenberger, Spies); the Department of Obstetrics and Gynecology, Medical University of Vienna, Austria (Kaufmann); the Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Hong Kong (Kranz)
| | - M Godbersen
- From the Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Kranz, Lanzenberger, Spies); the Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Lanzenberger, Spies); the Department of Obstetrics and Gynecology, Medical University of Vienna, Austria (Kaufmann); the Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Hong Kong (Kranz)
| | - Elisa Briem
- From the Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Kranz, Lanzenberger, Spies); the Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Lanzenberger, Spies); the Department of Obstetrics and Gynecology, Medical University of Vienna, Austria (Kaufmann); the Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Hong Kong (Kranz)
| | - René Seiger
- From the Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Kranz, Lanzenberger, Spies); the Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Lanzenberger, Spies); the Department of Obstetrics and Gynecology, Medical University of Vienna, Austria (Kaufmann); the Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Hong Kong (Kranz)
| | - Pia Baldinger-Melich
- From the Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Kranz, Lanzenberger, Spies); the Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Lanzenberger, Spies); the Department of Obstetrics and Gynecology, Medical University of Vienna, Austria (Kaufmann); the Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Hong Kong (Kranz)
| | - Georg S Kranz
- From the Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Kranz, Lanzenberger, Spies); the Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Lanzenberger, Spies); the Department of Obstetrics and Gynecology, Medical University of Vienna, Austria (Kaufmann); the Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Hong Kong (Kranz)
| | - Rupert Lanzenberger
- From the Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Kranz, Lanzenberger, Spies); the Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Lanzenberger, Spies); the Department of Obstetrics and Gynecology, Medical University of Vienna, Austria (Kaufmann); the Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Hong Kong (Kranz)
| | - Marie Spies
- From the Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Kranz, Lanzenberger, Spies); the Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Austria (Konadu, Reed, Handschuh, Spurny-Dworak, Klöbl, Schmidt, Godbersen, Briem, Seiger, Baldinger-Melich, Lanzenberger, Spies); the Department of Obstetrics and Gynecology, Medical University of Vienna, Austria (Kaufmann); the Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Hong Kong (Kranz)
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7
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Reed MB, Handschuh PA, Klöbl M, Konadu ME, Kaufmann U, Hahn A, Kranz GS, Spies M, Lanzenberger R. The influence of sex steroid treatment on insular connectivity in gender dysphoria. Psychoneuroendocrinology 2023; 155:106336. [PMID: 37499299 DOI: 10.1016/j.psyneuen.2023.106336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 07/16/2023] [Accepted: 07/17/2023] [Indexed: 07/29/2023]
Abstract
BACKGROUND Sex-specific differences in brain connectivity were found in various neuroimaging studies, though little is known about sex steroid effects on insular functioning. Based on well-characterized sex differences in emotion regulation, interoception and higher-level cognition, gender-dysphoric individuals receiving gender-affirming hormone therapy represent an interesting cohort to investigate how sex hormones might influence insular connectivity and related brain functions. METHODS To analyze the potential effect of sex steroids on insular connectivity at rest, 11 transgender women, 14 transgender men, 20 cisgender women, and 11 cisgender men were recruited. All participants underwent two magnetic resonance imaging sessions involving resting-state acquisitions separated by a median time period of 4.5 months and also completed the Bermond-Vorst alexithymia questionnaire at the initial and final examination. Between scans, transgender subjects received gender-affirming hormone therapy. RESULTS A seed based functional connectivity analysis revealed a significant 2-way interaction effect of group-by-time between right insula, cingulum, left middle frontal gyrus and left angular gyrus. Post-hoc tests demonstrated an increase in connectivity for transgender women when compared to cisgender men. Furthermore, spectral dynamic causal modelling showed reduced effective connectivity from the posterior cingulum and left angular gyrus to the left middle frontal gyrus as well as from the right insula to the left middle frontal gyrus. Alexithymia changes were found after gender-affirming hormone therapy for transgender women in both fantasizing and identifying. CONCLUSION These findings suggest a considerable influence of estrogen administration and androgen suppression on brain networks implicated in interoception, own-body perception and higher-level cognition.
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Affiliation(s)
- Murray B Reed
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - Patricia A Handschuh
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - Manfred Klöbl
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - Melisande E Konadu
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - Ulrike Kaufmann
- Department of Obstetrics and Gynecology, Medical University of Vienna, Austria
| | - Andreas Hahn
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - Georg S Kranz
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria; Department of Rehabilitation Sciences, Hong Kong Polytechnic University, Hong Kong, China
| | - Marie Spies
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - Rupert Lanzenberger
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria.
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8
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Skorska MN, Thurston LT, Biasin JM, Devenyi GA, Zucker KJ, Chakravarty MM, Lai MC, VanderLaan DP. Cortical Structure Differences in Relation to Age, Sexual Attractions, and Gender Dysphoria in Adolescents: An Examination of Mean Diffusivity and T1 Relaxation Time. Brain Sci 2023; 13:963. [PMID: 37371441 PMCID: PMC10296103 DOI: 10.3390/brainsci13060963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Revised: 06/08/2023] [Accepted: 06/13/2023] [Indexed: 06/29/2023] Open
Abstract
Recent research found that the combination of masculine gender identity and gynephilia was associated with cortical T1 relaxation time, which is considered to reflect gray matter density. We hypothesized that mean diffusivity (MD), a diffusion tensor imaging metric that reflects the degree to which water movement is free versus constrained, in combination with T1 relaxation time would provide further insight regarding cortical tissue characteristics. MD and T1 relaxation time were measured in 76 cortical regions in 15 adolescents assigned female at birth who experience gender dysphoria (GD AFAB) and were not receiving hormone therapy, 17 cisgender girls, and 14 cisgender boys (ages 12-17 years). Sexual orientation was represented by the degree of androphilia-gynephilia and the strength of sexual attraction. In multivariate analyses, cortical T1 relaxation time showed a weak but statistically significant positive association with MD across the cortex, suggesting that macromolecule-rich cortical tissue also tends to show water movement that is somewhat more constrained. In further multivariate analyses, in several left frontal, parietal, and temporal regions, the combination of shorter T1 relaxation time and faster MD was associated with older age and greater gynephilia in GD AFAB individuals and cisgender boys and with stronger attractions in cisgender boys only. Thus, for these cortical regions in these groups, older age, gynephilia, and stronger attractions (cisgender boys only) were associated with macromolecule-rich tissue in which water movement was freer-a pattern that some prior research suggests is associated with greater cell density and size. Overall, this study indicates that investigating T1 relaxation time and MD together can further inform how cortical gray matter tissue characteristics relate to age and psychosexuality.
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Affiliation(s)
- Malvina N. Skorska
- Child & Youth Psychiatry, Centre for Addiction and Mental Health, Toronto, ON M6J 1H4, Canada; (M.N.S.)
| | - Lindsey T. Thurston
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada
| | - Jessica M. Biasin
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada
| | - Gabriel A. Devenyi
- Cerebral Imaging Centre, Douglas Mental Health University Institute, Montreal, QC H4H 1R3, Canada (M.M.C.)
- Department of Psychiatry, McGill University, Montreal, QC H3A 1A1, Canada
| | - Kenneth J. Zucker
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5T 1R8, Canada
| | - M. Mallar Chakravarty
- Cerebral Imaging Centre, Douglas Mental Health University Institute, Montreal, QC H4H 1R3, Canada (M.M.C.)
- Department of Psychiatry, McGill University, Montreal, QC H3A 1A1, Canada
- Department of Biological and Biomedical Engineering, McGill University, Montreal, QC H3A 2B4, Canada
| | - Meng-Chuan Lai
- Child & Youth Psychiatry, Centre for Addiction and Mental Health, Toronto, ON M6J 1H4, Canada; (M.N.S.)
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5T 1R8, Canada
- The Margaret and Wallace McCain Centre for Child, Youth & Family Mental Health, Azrieli Adult Neurodevelopmental Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON M6J 1H4, Canada
- Department of Psychiatry and Autism Research Unit, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
- Autism Research Centre, Department of Psychiatry, University of Cambridge, Cambridge CB2 8AH, UK
- Department of Psychiatry, National Taiwan University Hospital and College of Medicine, Taipei 100229, Taiwan
| | - Doug P. VanderLaan
- Child & Youth Psychiatry, Centre for Addiction and Mental Health, Toronto, ON M6J 1H4, Canada; (M.N.S.)
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada
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9
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van Heesewijk J, Steenwijk MD, Kreukels BPC, Veltman DJ, Bakker J, Burke SM. Alterations in the inferior fronto-occipital fasciculus - a specific neural correlate of gender incongruence? Psychol Med 2023; 53:3461-3470. [PMID: 35301969 PMCID: PMC10277722 DOI: 10.1017/s0033291721005547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 11/06/2021] [Accepted: 12/28/2021] [Indexed: 11/05/2022]
Abstract
BACKGROUND Increasing numbers of adolescents seek help for gender-identity questions. Consequently, requests for medical treatments, such as puberty suppression, are growing. However, studies investigating the neurobiological substrate of gender incongruence (when birth-assigned sex and gender identity do not align) are scarce, and knowledge about the effects of puberty suppression on the developing brain of transgender youth is limited. METHODS Here we cross-sectionally investigated sex and gender differences in regional fractional anisotropy (FA) as measured by diffusion MR imaging, and the impact of puberty on alterations in the white-matter organization of 35 treatment-naive prepubertal children and 41 adolescents with gender incongruence, receiving puberty suppression. The transgender groups were compared with 79 age-matched, treatment-naive cisgender (when sex and gender align) peers. RESULTS We found that transgender adolescents had lower FA in the bilateral inferior fronto-occipital fasciculus (IFOF), forceps major and corpus callosum than cisgender peers. In addition, average FA values of the right IFOF correlated negatively with adolescents' cumulative dosage of puberty suppressants received. Of note, prepubertal children also showed significant FA group differences in, again, the right IFOF and left cortico-spinal tract, but with the reverse pattern (transgender > cisgender) than was seen in adolescents. CONCLUSIONS Importantly, our results of lower FA (indexing less longitudinal organization, fiber coherence, and myelination) in the IFOF of gender-incongruent adolescents replicate prior findings in transgender adults, suggesting a salient neural correlate of gender incongruence. Findings highlight the complexity with which (pubertal) sex hormones impact white-matter development and add important insight into the neurobiological substrate associated with gender incongruence.
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Affiliation(s)
- Jason van Heesewijk
- Center of Expertise on Gender Dysphoria, Amsterdam University Medical Centers, location VUmc, De Boelelaan 1131, Amsterdam, Noord-Holland, Netherlands
| | - Martijn D. Steenwijk
- Center of Expertise on Gender Dysphoria, Amsterdam University Medical Centers, location VUmc, De Boelelaan 1131, Amsterdam, Noord-Holland, Netherlands
| | - Baudewijntje P. C. Kreukels
- Center of Expertise on Gender Dysphoria, Amsterdam University Medical Centers, location VUmc, De Boelelaan 1131, Amsterdam, Noord-Holland, Netherlands
| | - Dick J. Veltman
- Center of Expertise on Gender Dysphoria, Amsterdam University Medical Centers, location VUmc, De Boelelaan 1131, Amsterdam, Noord-Holland, Netherlands
| | - Julie Bakker
- Center of Expertise on Gender Dysphoria, Amsterdam University Medical Centers, location VUmc, De Boelelaan 1131, Amsterdam, Noord-Holland, Netherlands
| | - Sarah M. Burke
- Center of Expertise on Gender Dysphoria, Amsterdam University Medical Centers, location VUmc, De Boelelaan 1131, Amsterdam, Noord-Holland, Netherlands
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10
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Kiyar M, Kubre MA, Collet S, Van Den Eynde T, T'Sjoen G, Guillamon A, Mueller SC. Gender-affirming hormonal treatment changes neural processing of emotions in trans men: An fMRI study. Psychoneuroendocrinology 2022; 146:105928. [PMID: 36155318 DOI: 10.1016/j.psyneuen.2022.105928] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 09/14/2022] [Accepted: 09/14/2022] [Indexed: 12/25/2022]
Abstract
BACKGROUND Some transgender people desire a transition through gender-affirming hormone treatment (GAHT). To date, it is unknown how GAHT changes emotion perception in transgender people. METHODS Thirty transgender men (TM), 30 cisgender men (CM), and 35 cisgender women (CW) underwent 3 Tesla functional magnetic resonance imaging (fMRI) while passively viewing emotional faces (happy, angry, surprised faces) at two timepoints (T0 and T1). At T0 all participants were hormone-naïve, while TM immediately commenced testosterone supplementation at T0. The second scanning session (T1) occurred after 6-10 months of GAHT in TM. All 3 groups completed both T0 and T1 RESULTS: GAHT in TM shifted the neural profile whilst processing emotions from a sex-assigned at birth pattern at T0 (similar to CW) to a consistent with gender identity pattern at T1 (similar to CM). Overall, the brain patterns stayed the same for the cis people at T0 and T1. CONCLUSIONS These findings document the impact of hormone treatment, and testosterone supplementation specifically, on emotion perception in TM.
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Affiliation(s)
- Meltem Kiyar
- Department of Experimental Clinical and Health Psychology, Ghent University, Belgium.
| | - Mary-Ann Kubre
- Department of Experimental Clinical and Health Psychology, Ghent University, Belgium
| | - Sarah Collet
- Department of Endocrinology, Ghent University Hospital, Belgium
| | | | - Guy T'Sjoen
- Department of Endocrinology, Ghent University Hospital, Belgium
| | - Antonio Guillamon
- Department of Psychobiology, National Distance Education University, Madrid, Spain
| | - Sven C Mueller
- Department of Experimental Clinical and Health Psychology, Ghent University, Belgium
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11
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Levin RN, Erickson-Schroth L, Mak K, Edmiston EK. Biological studies of transgender identity: A critical review. JOURNAL OF GAY & LESBIAN MENTAL HEALTH 2022. [DOI: 10.1080/19359705.2022.2127042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Rachel N. Levin
- Departments of Biology and Neuroscience, Pomona College, Claremont, CA, USA
| | | | - Kristie Mak
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - E. Kale Edmiston
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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12
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Skorska MN, Lobaugh NJ, Lombardo MV, van Bruggen N, Chavez S, Thurston LT, Aitken M, Zucker KJ, Chakravarty MM, Lai MC, VanderLaan DP. Inter-Network Brain Functional Connectivity in Adolescents Assigned Female at Birth Who Experience Gender Dysphoria. Front Endocrinol (Lausanne) 2022; 13:903058. [PMID: 35937791 PMCID: PMC9353716 DOI: 10.3389/fendo.2022.903058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 06/15/2022] [Indexed: 11/13/2022] Open
Abstract
Gender dysphoria (GD) is characterized by distress due to an incongruence between experienced gender and sex assigned at birth. Brain functional connectivity in adolescents who experience GD may be associated with experienced gender (vs. assigned sex) and/or brain networks implicated in own-body perception. Furthermore, sexual orientation may be related to brain functional organization given commonalities in developmental mechanisms proposed to underpin GD and same-sex attractions. Here, we applied group independent component analysis to resting-state functional magnetic resonance imaging (rs-fMRI) BOLD timeseries data to estimate inter-network (i.e., between independent components) timeseries correlations, representing functional connectivity, in 17 GD adolescents assigned female at birth (AFAB) not receiving gender-affirming hormone therapy, 17 cisgender girls, and 15 cisgender boys (ages 12-17 years). Sexual orientation was represented by degree of androphilia-gynephilia and sexual attractions strength. Multivariate partial least squares analyses found that functional connectivity differed among cisgender boys, cisgender girls, and GD AFAB, with the largest difference between cisgender boys and GD AFAB. Regarding sexual orientation and age, the brain's intrinsic functional organization of GD AFAB was both similar to and different from cisgender girls, and both differed from cisgender boys. The pattern of group differences and the networks involved aligned with the hypothesis that brain functional organization is different among GD AFAB (vs. cisgender) adolescents, and certain aspects of this organization relate to brain areas implicated in own-body perception and self-referential thinking. Overall, brain functional organization of GD AFAB was generally more similar to that of cisgender girls than cisgender boys.
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Affiliation(s)
- Malvina N. Skorska
- Child and Youth Psychiatry, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Nancy J. Lobaugh
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Medicine, Division of Neurology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Michael V. Lombardo
- Laboratory for Autism and Neurodevelopmental Disorders, Center for Neuroscience and Cognitive Systems @UniTn, Istituto Italiano di Tecnologia, Rovereto, Italy
| | - Nina van Bruggen
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON, Canada
| | - Sofia Chavez
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Lindsey T. Thurston
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON, Canada
| | - Madison Aitken
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Kenneth J. Zucker
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - M. Mallar Chakravarty
- Cerebral Imaging Centre, Douglas Mental Health University Institute, Montreal, PQ, Canada
- Department of Psychiatry, McGill University, Montreal, PQ, Canada
- Department of Biological and Biomedical Engineering, McGill University, Montreal, PQ, Canada
| | - Meng-Chuan Lai
- Child and Youth Psychiatry, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- The Margaret and Wallace McCain Centre for Child, Youth & Family Mental Health and Azrieli Adult Neurodevelopmental Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychiatry and Autism Research Unit, The Hospital for Sick Children, Toronto, ON, Canada
- Department of Psychiatry, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan
- Autism Research Centre, Department of Psychiatry, University of Cambridge, Cambridge, United Kingdom
| | - Doug P. VanderLaan
- Child and Youth Psychiatry, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON, Canada
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13
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The Impact of Gender-affirming Hormone Therapy on Anatomic Structures of the Brain Among Transgender Individuals. J Psychiatr Pract 2022; 28:328-334. [PMID: 35797690 DOI: 10.1097/pra.0000000000000633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Despite the growing numbers of individuals who identify as transgender, this population continues to face worse mental health outcomes compared with the general population. Transgender individuals attempt suicide at a rate that is almost 9 times that of the general population. Few studies have reported on the positive effect of gender-affirming hormone therapy on mental health outcomes in transgender individuals. It is likely that this effect is due in part to the physiological responses that occur as a result of hormone therapy that mitigate incongruencies between one's gender identity and assigned sex. To our knowledge, only limited studies have shown a connection between gender-affirming hormone therapy, its effect on the brain's structure, and long-term effects that this may have on mental health outcomes. The authors propose that, in addition to the physiological responses that occur as a direct result of hormone therapy and the validation that results from receiving gender-affirming medical care, mental health outcomes in transgender individuals may also improve due to the role that hormone therapy plays in altering the brain's structure, possibly shaping the brain to become more like that of the gender with which an individual identifies. In this article, the authors review the current literature on the effects that gender-affirming hormone therapy has on mental health outcomes and anatomic structures of the brain in transgender individuals.
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14
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Cherry MJ. What Happens if the Brain Goes Elsewhere? Reflections on Head Transplantation and Personal Embodiment. THE JOURNAL OF MEDICINE AND PHILOSOPHY 2022; 47:240-256. [PMID: 35543468 DOI: 10.1093/jmp/jhab045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Brain transplants have long been no more than the subject of science fiction and engaging thought experiments. That is no longer true. Neuroscientists have announced their intention to transplant the head of a volunteer onto a donated body. Response has been decidedly mixed. How should we think about the moral permissibility of head transplants? Is it a life-saving/life-enhancing opportunity that appropriately expands the boundaries of medical practice? Or, is it a bioethical morass that ought not to be attempted? For the purposes of this paper, I set aside questions regarding the surgical operation's technological plausibility so as to focus on very basic questions regarding personal identity and the morality of head transplantation. The analysis begins with an exploration of the embodiment of persons. It considers whether persons can be conceptually distinguished from all parts of their body, even if they cannot be physically separated from some parts without loss of personhood. It argues that in most cases replacing body parts with reasonably similar parts will not destroy the conditions for sustaining personhood. However, as I explore, the phenomenology of personhood is such that some physical changes may prove to be too significant to maintain personal identity successfully over time. Given such complexity and the significance of the costs involved, the moral permissibility of head transplantation likely depends on recognizing that persons may give permission to collaborate in common activities, including projects with which others deeply disagree, provided that they only utilize the services and resources of free and consenting others.
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15
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Brain Sex in Transgender Women Is Shifted towards Gender Identity. J Clin Med 2022; 11:jcm11061582. [PMID: 35329908 PMCID: PMC8955456 DOI: 10.3390/jcm11061582] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 03/07/2022] [Accepted: 03/09/2022] [Indexed: 01/09/2023] Open
Abstract
Transgender people report discomfort with their birth sex and a strong identification with the opposite sex. The current study was designed to shed further light on the question of whether the brains of transgender people resemble their birth sex or their gender identity. For this purpose, we analyzed a sample of 24 cisgender men, 24 cisgender women, and 24 transgender women before gender-affirming hormone therapy. We employed a recently developed multivariate classifier that yields a continuous probabilistic (rather than a binary) estimate for brains to be male or female. The brains of transgender women ranged between cisgender men and cisgender women (albeit still closer to cisgender men), and the differences to both cisgender men and to cisgender women were significant (p = 0.016 and p < 0.001, respectively). These findings add support to the notion that the underlying brain anatomy in transgender people is shifted away from their biological sex towards their gender identity.
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16
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Rainville JR, Lipuma T, Hodes GE. Translating the Transcriptome: Sex Differences in the Mechanisms of Depression and Stress, Revisited. Biol Psychiatry 2022; 91:25-35. [PMID: 33865609 PMCID: PMC10197090 DOI: 10.1016/j.biopsych.2021.02.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 02/01/2021] [Accepted: 02/01/2021] [Indexed: 12/28/2022]
Abstract
The past decade has produced a plethora of studies examining sex differences in the transcriptional profiles of stress and mood disorders. As we move forward from accepting the existence of extensive molecular sex differences in the brain to exploring the purpose of these sex differences, our approach must become more systemic and less reductionist. Earlier studies have examined specific brain regions and/or cell types. To use this knowledge to develop the next generation of personalized medicine, we need to comprehend how transcriptional changes across the brain and/or the body relate to each other. We provide an overview of the relationships between baseline and depression/stress-related transcriptional sex differences and explore contributions of preclinically identified mechanisms and their impacts on behavior.
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Affiliation(s)
- Jennifer R Rainville
- Department of Neuroscience, Virginia Polytechnic and State University, Blacksburg, Virginia
| | - Timothy Lipuma
- Department of Neuroscience, Virginia Polytechnic and State University, Blacksburg, Virginia
| | - Georgia E Hodes
- Department of Neuroscience, Virginia Polytechnic and State University, Blacksburg, Virginia.
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17
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Zubiaurre-Elorza L, Cerdán S, Uribe C, Pérez-Laso C, Marcos A, Rodríguez del Cerro MC, Fernandez R, Pásaro E, Guillamon A. The Effects of Testosterone on the Brain of Transgender Men. ANDROGENS: CLINICAL RESEARCH AND THERAPEUTICS 2021; 2:252-260. [PMID: 35024694 PMCID: PMC8744429 DOI: 10.1089/andro.2021.0008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Accepted: 07/21/2021] [Indexed: 01/28/2023]
Abstract
Transgender men (TM) experience an incongruence between the female sex assigned when they were born and their self-perceived male identity. Some TM seek for a gender affirming hormone treatment (GAHT) to induce a somatic transition from female to male through continuous administration of testosterone. GAHT seems to be relatively safe. However, testosterone produces structural changes in the brain as detected by quantitative magnetic resonance imaging. Mainly, it induces an increase in cortical volume and thickness and subcortical structural volume probably due to the anabolic effects. Animal models, specifically developed to test the anabolic hypothesis, suggest that testosterone and estradiol, its aromatized metabolite, participate in the control of astrocyte water trafficking, thereby controlling brain volume.
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Affiliation(s)
- Leire Zubiaurre-Elorza
- Department of Methods and Experimental Psychology, Faculty of Psychology and Education, University of Deusto, Bilbao, Spain
| | - Sebastian Cerdán
- Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Carme Uribe
- Institute of Neuroscience, University of Barcelona, Barcelona, Spain
| | - Carmen Pérez-Laso
- Departamento de Psicobiología, Universidad Nacional de Educación a Distancia, Madrid, Spain
| | - Alberto Marcos
- Departamento de Psicobiología, Universidad Nacional de Educación a Distancia, Madrid, Spain
| | | | - Rosa Fernandez
- Departamento de Psicología, Facultade de Ciencias da Educación, Universidade da Coruña, A Coruña, Spain
| | - Eduardo Pásaro
- Departamento de Psicología, Facultade de Ciencias da Educación, Universidade da Coruña, A Coruña, Spain
| | - Antonio Guillamon
- Departamento de Psicobiología, Universidad Nacional de Educación a Distancia, Madrid, Spain
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18
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Anderson AM, Ford J. Transgender adolescent and young adult suicide: A bioecological perspective. Nurs Inq 2021; 29:e12476. [PMID: 34796570 DOI: 10.1111/nin.12476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 11/01/2021] [Accepted: 11/04/2021] [Indexed: 11/27/2022]
Abstract
Suicide is a public health crisis disproportionately affecting transgender adolescents and young adults. There are gaps in research evaluating this phenomenon using a multilevel, life-course approach. The following paper will provide an overview of the current models of suicide, critique their applicability to understanding suicide among transgender youth, and discuss how using a bioecological systems approach will help to advance our understanding of suicide among transgender youth. Transgender adolescents and young adults often face unique combinations of interpersonal and intrapersonal challenges that require managing a stark misalignment of social characters, expectations, and roles. These factors are imposed by the complex interactions and influences of the bioecological systems in which transgender adolescents and young adults are situated. Future research is needed to elucidate the characteristics of bioecological adversity faced by this vulnerable population. Identification of these relationships are likely to highlight effective targets for multilevel interventions aimed at preventing suicide.
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Affiliation(s)
- Avery M Anderson
- Martha S. Pitzer Center for Women, Children and Youth, College of Nursing, The Ohio State University, Columbus, Ohio, USA
| | - Jodi Ford
- Martha S. Pitzer Center for Women, Children and Youth, College of Nursing, The Ohio State University, Columbus, Ohio, USA
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19
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Brain connectivity dynamics in cisgender and transmen people with gender incongruence before gender affirmative hormone treatment. Sci Rep 2021; 11:21036. [PMID: 34702875 PMCID: PMC8548343 DOI: 10.1038/s41598-021-00508-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 10/13/2021] [Indexed: 11/08/2022] Open
Abstract
Large-scale brain network interactions have been described between trans- and cis-gender binary identities. However, a temporal perspective of the brain's spontaneous fluctuations is missing. We investigated the functional connectivity dynamics in transmen with gender incongruence and its relationship with interoceptive awareness. We describe four states in native and meta-state spaces: (i) one state highly prevalent with sparse overall connections; (ii) a second with strong couplings mainly involving components of the salience, default, and executive control networks. Two states with global sparse connectivity but positive couplings (iii) within the sensorimotor network, and (iv) between salience network regions. Transmen had more dynamical fluidity than cismen, while cismen presented less meta-state fluidity and range dynamism than transmen and ciswomen. A positive association between attention regulation and fluidity and meta-state range dynamism was found in transmen. There exist gender differences in the temporal brain dynamism, characterized by distinct interrelations of the salience network as catalyst interacting with other networks. We offer a functional explanation from the neurodevelopmental cortical hypothesis of a gendered-self.
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20
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Wang Y, Khorashad BS, Feusner JD, Savic I. Cortical Gyrification in Transgender Individuals. Cereb Cortex 2021; 31:3184-3193. [PMID: 33718960 PMCID: PMC8324983 DOI: 10.1093/cercor/bhaa412] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 12/20/2020] [Accepted: 12/23/2020] [Indexed: 12/26/2022] Open
Abstract
Gender incongruence (GI) is characterized by a feeling of estrangement from the own body in the context of self. GI is often described in people who identify as transgender. The underlying mechanisms are unknown. Data from MRI measurements and tests of own body perception triggered us to pose a model that GI in transgender persons (TGI) could be associated with a disconnection within the brain circuits mediating the perception of own body as self. This is a departure from a previous model of sex atypical cerebral dimorphism, introducing a concept that better accords with a core feature of TGI. The present MRI study of 54 hormone naive transmen (TrM), 38 transwomen (TrW), 44 cismen and 41 ciswomen show that cortical gyrification, a metric that reflects early maturation of cerebral cortex, is significantly lower in transgender compared with cisgender participants. This reduction is limited to the occipito-parietal cortex and the sensory motor cortex, regions encoding own body image and body ownership. Moreover, the cortical gyrification correlated inversely with own body-self incongruence in these regions. These novel data suggest that GI in TGI may originate in the neurodevelopment of body image encoding regions. The results add potentially to understanding neurobiological contributors to gender identity.
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Affiliation(s)
- Yanlu Wang
- Department of Clinical Science, Intervention and Technology, Karolinska Institute, Stockholm 171 77, Sweden
- MR Physics, Medical Radiation Physics and Nuclear Medicine, Karolinska University Hospital, Stockholm 171 76, Sweden
| | - Behzad S Khorashad
- Department of Women’s and Children’s Health, Karolinska Institutet, Stockholm 171 77, Sweden
| | - Jamie D Feusner
- Department of Women’s and Children’s Health, Karolinska Institutet, Stockholm 171 77, Sweden
- Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Ivanka Savic
- Department of Women’s and Children’s Health, Karolinska Institutet, Stockholm 171 77, Sweden
- Department of Neurology, University of California Los Angeles, Los Angeles, CA 90095-6975, USA
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21
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Bhargava A, Arnold AP, Bangasser DA, Denton KM, Gupta A, Hilliard Krause LM, Mayer EA, McCarthy M, Miller WL, Raznahan A, Verma R. Considering Sex as a Biological Variable in Basic and Clinical Studies: An Endocrine Society Scientific Statement. Endocr Rev 2021; 42:219-258. [PMID: 33704446 PMCID: PMC8348944 DOI: 10.1210/endrev/bnaa034] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Indexed: 02/08/2023]
Abstract
In May 2014, the National Institutes of Health (NIH) stated its intent to "require applicants to consider sex as a biological variable (SABV) in the design and analysis of NIH-funded research involving animals and cells." Since then, proposed research plans that include animals routinely state that both sexes/genders will be used; however, in many instances, researchers and reviewers are at a loss about the issue of sex differences. Moreover, the terms sex and gender are used interchangeably by many researchers, further complicating the issue. In addition, the sex or gender of the researcher might influence study outcomes, especially those concerning behavioral studies, in both animals and humans. The act of observation may change the outcome (the "observer effect") and any experimental manipulation, no matter how well-controlled, is subject to it. This is nowhere more applicable than in physiology and behavior. The sex of established cultured cell lines is another issue, in addition to aneuploidy; chromosomal numbers can change as cells are passaged. Additionally, culture medium contains steroids, growth hormone, and insulin that might influence expression of various genes. These issues often are not taken into account, determined, or even considered. Issues pertaining to the "sex" of cultured cells are beyond the scope of this Statement. However, we will discuss the factors that influence sex and gender in both basic research (that using animal models) and clinical research (that involving human subjects), as well as in some areas of science where sex differences are routinely studied. Sex differences in baseline physiology and associated mechanisms form the foundation for understanding sex differences in diseases pathology, treatments, and outcomes. The purpose of this Statement is to highlight lessons learned, caveats, and what to consider when evaluating data pertaining to sex differences, using 3 areas of research as examples; it is not intended to serve as a guideline for research design.
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Affiliation(s)
- Aditi Bhargava
- Center for Reproductive Sciences, San Francisco, CA, USA
- Department of Obstetrics and Gynecology, University of California, San Francisco, CA, USA
| | - Arthur P Arnold
- Department of Integrative Biology & Physiology, University of California, Los Angeles, Los Angeles, CA, USA
| | - Debra A Bangasser
- Department of Psychology and Neuroscience Program, Temple University, Philadelphia, PA, USA
| | - Kate M Denton
- Cardiovascular Disease Program, Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, Victoria, Australia
| | - Arpana Gupta
- G. Oppenheimer Center for Neurobiology of Stress and Resilience, Division of Digestive Diseases, University of California, Los Angeles, Los Angeles, CA, USA
| | - Lucinda M Hilliard Krause
- Cardiovascular Disease Program, Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, Victoria, Australia
| | - Emeran A Mayer
- G. Oppenheimer Center for Neurobiology of Stress and Resilience, Division of Digestive Diseases, University of California, Los Angeles, Los Angeles, CA, USA
| | - Margaret McCarthy
- Department of Pharmacology and Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Walter L Miller
- Center for Reproductive Sciences, San Francisco, CA, USA
- Department of Pediatrics, University of California, San Francisco, CA, USA
| | - Armin Raznahan
- Section on Developmental Neurogenomics, Human Genetics Branch, National Institutes of Mental Health, Intramural Research Program, Bethesda, MD, USA
| | - Ragini Verma
- Diffusion and Connectomics In Precision Healthcare Research (DiCIPHR) lab, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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22
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Llaveria Caselles E. Epistemic Injustice in Brain Studies of (Trans)Gender Identity. FRONTIERS IN SOCIOLOGY 2021; 6:608328. [PMID: 33869551 PMCID: PMC8022811 DOI: 10.3389/fsoc.2021.608328] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Accepted: 03/02/2021] [Indexed: 06/12/2023]
Abstract
This study undertakes an analysis of the conceptualization of gender identity in neuroscientific studies of (trans)gender identity that contrast the brains of cisgender and transgender participants. The analysis focuses on instances of epistemic injustice that combine scientific deficiencies and the exclusion of relevant bodies of knowledge. The results of a content analysis show how the ignoring of biosocial, developmental, mosaicist, contextualist, and depathologizing approaches leads to internal conceptual inconsistencies, hermeneutical deficiencies and the upholding of questionable paradigms in the research field. Interviews with researchers involved in these brain studies reveal targeted and diffuse forms of testimonial injustice against alternative approaches, promoted by the hierarchical arrangements of research teams in combination with the careerist and economic logic of research. The analysis points to the exclusion of critical epistemologies of science and the historical oppression of trans people as epistemic agents as the underlying hermeneutical deficiencies.
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23
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Khorashad BS, Manzouri A, Feusner JD, Savic I. Cross-sex hormone treatment and own-body perception: behavioral and brain connectivity profiles. Sci Rep 2021; 11:2799. [PMID: 33531529 PMCID: PMC7854619 DOI: 10.1038/s41598-020-80687-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 12/08/2020] [Indexed: 12/03/2022] Open
Abstract
Referrals for gender dysphoria (GD), characterized by a distressful incongruence between gender identity and at-birth assigned sex, are steadily increasing. The underlying neurobiology, and the mechanisms of the often-beneficial cross-sex hormone treatment are unknown. Here, we test hypothesis that own body perception networks (incorporated in the default mode network—DMN, and partly in the salience network—SN), are different in trans-compared with cis-gender persons. We also investigate whether these networks change with cross-sex hormone treatment. Forty transmen (TrM) and 25 transwomen (TrW) were scanned before and after cross-sex hormone institution. We used our own developed Body Morph test (BM), to assess the perception of own body as self. Fifteen cisgender persons were controls. Within and between-group differences in functional connectivity were calculated using independent components analysis within the DMN, SN, and motor network (a control network). Pretreatment, TrM and TrW scored lower “self” on the BM test than controls. Their functional connections were weaker in the anterior cingulate-, mesial prefrontal-cortex (mPFC), precuneus, the left angular gyrus, and superior parietal cortex of the DMN, and ACC in the SN “Self” identification and connectivity in the mPFC in both TrM and TrW increased from scan 1 to 2, and at scan 2 no group differences remained. The neurobiological underpinnings of GD seem subserved by cerebral structures composing major parts of the DMN.
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Affiliation(s)
- Behzad S Khorashad
- Department of Women's and Children's Health, Karolinska Hospital, Karolinska Institutet, Q2:07, 171 76, Stockholm, Sweden
| | | | - Jamie D Feusner
- Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, USA
| | - Ivanka Savic
- Department of Women's and Children's Health, Karolinska Hospital, Karolinska Institutet, Q2:07, 171 76, Stockholm, Sweden. .,Department of Neurology, University of California Los Angeles, Los Angeles, USA.
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24
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A Multi-Modal MRI Analysis of Cortical Structure in Relation to Gender Dysphoria, Sexual Orientation, and Age in Adolescents. J Clin Med 2021; 10:jcm10020345. [PMID: 33477567 PMCID: PMC7831120 DOI: 10.3390/jcm10020345] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/20/2020] [Accepted: 12/23/2020] [Indexed: 01/18/2023] Open
Abstract
Gender dysphoria (GD) is characterized by distress due to an incongruence between experienced gender and sex assigned at birth. Sex-differentiated brain regions are hypothesized to reflect the experienced gender in GD and may play a role in sexual orientation development. Magnetic resonance brain images were acquired from 16 GD adolescents assigned female at birth (AFAB) not receiving hormone therapy, 17 cisgender girls, and 14 cisgender boys (ages 12–17 years) to examine three morphological and microstructural gray matter features in 76 brain regions: surface area (SA), cortical thickness (CT), and T1 relaxation time. Sexual orientation was represented by degree of androphilia-gynephilia and sexual attraction strength. Multivariate analyses found that cisgender boys had larger SA than cisgender girls and GD AFAB. Shorter T1, reflecting denser, macromolecule-rich tissue, correlated with older age and stronger gynephilia in cisgender boys and GD AFAB, and with stronger attractions in cisgender boys. Thus, cortical morphometry (mainly SA) was related to sex assigned at birth, but not experienced gender. Effects of experienced gender were found as similarities in correlation patterns in GD AFAB and cisgender boys in age and sexual orientation (mainly T1), indicating the need to consider developmental trajectories and sexual orientation in brain studies of GD.
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25
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Predicting outcomes of cross-sex hormone therapy in transgender individuals with gender incongruence based on pre-therapy resting-state brain connectivity. NEUROIMAGE-CLINICAL 2020; 29:102517. [PMID: 33340976 PMCID: PMC7750413 DOI: 10.1016/j.nicl.2020.102517] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 10/06/2020] [Accepted: 11/25/2020] [Indexed: 12/29/2022]
Abstract
Individuals with gender incongruence (GI) experience serious distress due to incongruence between their gender identity and birth-assigned sex. Sociological, cultural, interpersonal, and biological factors are likely contributory, and for some individuals medical treatment such as cross-sex hormone therapy and gender-affirming surgery can be helpful. Cross-sex hormone therapy can be effective for reducing body incongruence, but responses vary, and there is no reliable way to predict therapeutic outcomes. We used clinical and MRI data before cross-sex hormone therapy as features to train a machine learning model to predict individuals' post-therapy body congruence (the degree to which photos of their bodies match their self-identities). Twenty-five trans women and trans men with gender incongruence participated. The model significantly predicted post-therapy body congruence, with the highest predictive features coming from the cingulo-opercular (R2 = 0.41) and fronto-parietal (R2 = 0.30) networks. This study provides evidence that hormone therapy efficacy can be predicted from information collected before therapy, and that patterns of functional brain connectivity may provide insights into body-brain effects of hormones, affecting one's sense of body congruence. Results could help identify the need for personalized therapies in individuals predicted to have low body-self congruence after standard therapy.
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26
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Tacikowski P, Fust J, Ehrsson HH. Fluidity of gender identity induced by illusory body-sex change. Sci Rep 2020; 10:14385. [PMID: 32873869 PMCID: PMC7463009 DOI: 10.1038/s41598-020-71467-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 08/11/2020] [Indexed: 12/13/2022] Open
Abstract
Gender identity is a collection of thoughts and feelings about one’s own gender, which may or may not correspond to the sex assigned at birth. How this sense is linked to the perception of one’s own masculine or feminine body remains unclear. Here, in a series of three behavioral experiments conducted on a large group of control volunteers (N = 140), we show that a perceptual illusion of having the opposite-sex body is associated with a shift toward a more balanced identification with both genders and less gender-stereotypical beliefs about own personality characteristics, as indicated by subjective reports and implicit behavioral measures. These findings demonstrate that the ongoing perception of one’s own body affects the sense of one’s own gender in a dynamic, robust, and automatic manner.
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Affiliation(s)
- Pawel Tacikowski
- Department of Neuroscience, Karolinska Institute, Stockholm, Sweden. .,Department of Neurosurgery, Univeristy of California Los Angeles, Los Angeles, USA.
| | - Jens Fust
- Department of Neuroscience, Karolinska Institute, Stockholm, Sweden.,Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden
| | - H Henrik Ehrsson
- Department of Neuroscience, Karolinska Institute, Stockholm, Sweden
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27
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Flint C, Förster K, Koser SA, Konrad C, Zwitserlood P, Berger K, Hermesdorf M, Kircher T, Nenadic I, Krug A, Baune BT, Dohm K, Redlich R, Opel N, Arolt V, Hahn T, Jiang X, Dannlowski U, Grotegerd D. Biological sex classification with structural MRI data shows increased misclassification in transgender women. Neuropsychopharmacology 2020; 45:1758-1765. [PMID: 32272482 PMCID: PMC7419542 DOI: 10.1038/s41386-020-0666-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 02/28/2020] [Accepted: 03/23/2020] [Indexed: 12/14/2022]
Abstract
Transgender individuals (TIs) show brain-structural alterations that differ from their biological sex as well as their perceived gender. To substantiate evidence that the brain structure of TIs differs from male and female, we use a combined multivariate and univariate approach. Gray matter segments resulting from voxel-based morphometry preprocessing of N = 1753 cisgender (CG) healthy participants were used to train (N = 1402) and validate (20% holdout N = 351) a support-vector machine classifying the biological sex. As a second validation, we classified N = 1104 patients with depression. A third validation was performed using the matched CG sample of the transgender women (TW) application sample. Subsequently, the classifier was applied to N = 26 TW. Finally, we compared brain volumes of CG-men, women, and TW-pre/post treatment cross-sex hormone treatment (CHT) in a univariate analysis controlling for sexual orientation, age, and total brain volume. The application of our biological sex classifier to the transgender sample resulted in a significantly lower true positive rate (TPR-male = 56.0%). The TPR did not differ between CG-individuals with (TPR-male = 86.9%) and without depression (TPR-male = 88.5%). The univariate analysis of the transgender application-sample revealed that TW-pre/post treatment show brain-structural differences from CG-women and CG-men in the putamen and insula, as well as the whole-brain analysis. Our results support the hypothesis that brain structure in TW differs from brain structure of their biological sex (male) as well as their perceived gender (female). This finding substantiates evidence that TIs show specific brain-structural alterations leading to a different pattern of brain structure than CG-individuals.
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Affiliation(s)
- Claas Flint
- grid.5949.10000 0001 2172 9288Department of Psychiatry, University of Münster, Albert Schweitzer-Campus 1, A9, 48149 Münster, Germany ,grid.5949.10000 0001 2172 9288Department of Computer Science, University of Münster, Einsteinstraße 62, 48149 Münster, Germany
| | - Katharina Förster
- grid.5949.10000 0001 2172 9288Department of Psychiatry, University of Münster, Albert Schweitzer-Campus 1, A9, 48149 Münster, Germany
| | - Sophie A. Koser
- grid.5949.10000 0001 2172 9288Department of Psychiatry, University of Münster, Albert Schweitzer-Campus 1, A9, 48149 Münster, Germany
| | - Carsten Konrad
- grid.440210.30000 0004 0560 2107Department of Psychiatry and Psychotherapy, Agaplesion Diakonieklinikum, 27356 Rotenburg, Germany
| | - Pienie Zwitserlood
- grid.5949.10000 0001 2172 9288Department of Psychology, University of Münster, Fliednerstraße 21, 48149 Münster, Germany
| | - Klaus Berger
- grid.5949.10000 0001 2172 9288Department of Epidemiology and Social Medicine, University of Münster, Albert Schweitzer-Campus 1, D3, 48149 Münster, Germany
| | - Marco Hermesdorf
- grid.5949.10000 0001 2172 9288Department of Epidemiology and Social Medicine, University of Münster, Albert Schweitzer-Campus 1, D3, 48149 Münster, Germany
| | - Tilo Kircher
- grid.10253.350000 0004 1936 9756Department of Psychiatry and Psychotherapy, University of Marburg, Marburg, Germany
| | - Igor Nenadic
- grid.10253.350000 0004 1936 9756Department of Psychiatry and Psychotherapy, University of Marburg, Marburg, Germany
| | - Axel Krug
- grid.10253.350000 0004 1936 9756Department of Psychiatry and Psychotherapy, University of Marburg, Marburg, Germany
| | - Bernhard T. Baune
- grid.5949.10000 0001 2172 9288Department of Psychiatry, University of Münster, Albert Schweitzer-Campus 1, A9, 48149 Münster, Germany ,grid.1008.90000 0001 2179 088XDepartment of Psychiatry, Melbourne Medical School, The University of Melbourne, Parkville, VIC Australia ,grid.1008.90000 0001 2179 088XThe Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC Australia
| | - Katharina Dohm
- grid.5949.10000 0001 2172 9288Department of Psychiatry, University of Münster, Albert Schweitzer-Campus 1, A9, 48149 Münster, Germany
| | - Ronny Redlich
- grid.5949.10000 0001 2172 9288Department of Psychiatry, University of Münster, Albert Schweitzer-Campus 1, A9, 48149 Münster, Germany
| | - Nils Opel
- grid.5949.10000 0001 2172 9288Department of Psychiatry, University of Münster, Albert Schweitzer-Campus 1, A9, 48149 Münster, Germany
| | - Volker Arolt
- grid.5949.10000 0001 2172 9288Department of Psychiatry, University of Münster, Albert Schweitzer-Campus 1, A9, 48149 Münster, Germany
| | - Tim Hahn
- grid.5949.10000 0001 2172 9288Department of Psychiatry, University of Münster, Albert Schweitzer-Campus 1, A9, 48149 Münster, Germany
| | - Xiaoyi Jiang
- grid.5949.10000 0001 2172 9288Department of Computer Science, University of Münster, Einsteinstraße 62, 48149 Münster, Germany
| | - Udo Dannlowski
- Department of Psychiatry, University of Münster, Albert Schweitzer-Campus 1, A9, 48149, Münster, Germany.
| | - Dominik Grotegerd
- grid.5949.10000 0001 2172 9288Department of Psychiatry, University of Münster, Albert Schweitzer-Campus 1, A9, 48149 Münster, Germany
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28
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Neural Correlates of Gender Face Perception in Transgender People. J Clin Med 2020; 9:jcm9061731. [PMID: 32503300 PMCID: PMC7356844 DOI: 10.3390/jcm9061731] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 05/26/2020] [Accepted: 06/01/2020] [Indexed: 02/06/2023] Open
Abstract
To date, MRI studies focused on brain sexual dimorphism have not explored the presence of specific neural patterns in gender dysphoria (GD) using gender discrimination tasks. Considering the central role of body image in GD, the present study aims to evaluate brain activation patterns with 3T-scanner functional MRI (fMRI) during gender face discrimination task in a sample of 20 hormone-naïve transgender and 20 cisgender individuals. Additionally, participants were asked to complete psychometric measures. The between-group analysis of average blood oxygenation level dependent (BOLD) activations of female vs. male face contrast showed a significant positive cluster in the bilateral precuneus in transmen when compared to the ciswomen. In addition. the transwomen group compared to the cismen showed higher activations also in the precuneus, as well as in the posterior cingulate gyrus, the angular gyrus and the lateral occipital cortices. Moreover, the activation of precuneus, angular gyrus, lateral occipital cortices and posterior cingulate gyrus was significantly associated with higher levels of body uneasiness. These results show for the first time the existence of a possible specific GD-neural pattern. However, it remains unclear if the differences in brain phenotype of transgender people may be the result of a sex-atypical neural development or of a lifelong experience of gender non-conformity.
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29
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Kranz GS, Zhang BBB, Handschuh P, Ritter V, Lanzenberger R. Gender-affirming hormone treatment - A unique approach to study the effects of sex hormones on brain structure and function. Cortex 2020; 129:68-79. [PMID: 32438011 DOI: 10.1016/j.cortex.2020.04.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 03/23/2020] [Accepted: 04/09/2020] [Indexed: 12/22/2022]
Abstract
Investigating the effects of the gender-affirming hormone treatment of transgender people using neuroimaging provides a unique opportunity to study the impact of high dosages of sex hormones on human brain structure and function. This line of research is of relevance from a basic neuroscientific as well as from a psychiatric viewpoint. Prevalence rates, etiopathology, and disease course of many psychiatric disorders exhibit sex differences which are linked to differences in sex hormone levels. Here, we review recent neuroimaging studies from others and our group that investigate the effects of gender-affirming hormone treatment in a longitudinal design utilizing structural and functional magnetic resonance imaging and positron emission tomography. Studies point to a general anabolic and anticatabolic effect of testosterone on grey and white matter structure, whereas estradiol and antiandrogen treatment seems to have partly opposite effects. Moreover, preliminary research indicates that gender-affirming hormone treatment influences serotonergic neurotransmission, a finding that is especially interesting for psychiatry. A clear picture of a hormonal influence on brain activity has yet to emerge. In conclusion, the available evidence reviewed here clearly indicates that sex hormone applications influence brain structure and function in the adult human brain.
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Affiliation(s)
- Georg S Kranz
- Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hong Kong, SAR, China; Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria; The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, SAR, China.
| | - Bella B B Zhang
- Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hong Kong, SAR, China
| | - Patricia Handschuh
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
| | - Vera Ritter
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
| | - Rupert Lanzenberger
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
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30
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Clemens B, Derntl B, Smith E, Junger J, Neulen J, Mingoia G, Schneider F, Abel T, Bzdok D, Habel U. Predictive Pattern Classification Can Distinguish Gender Identity Subtypes from Behavior and Brain Imaging. Cereb Cortex 2020; 30:2755-2765. [PMID: 31999324 DOI: 10.1093/cercor/bhz272] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 08/02/2019] [Accepted: 09/12/2019] [Indexed: 11/13/2022] Open
Abstract
The exact neurobiological underpinnings of gender identity (i.e., the subjective perception of oneself belonging to a certain gender) still remain unknown. Combining both resting-state functional connectivity and behavioral data, we examined gender identity in cisgender and transgender persons using a data-driven machine learning strategy. Intrinsic functional connectivity and questionnaire data were obtained from cisgender (men/women) and transgender (trans men/trans women) individuals. Machine learning algorithms reliably detected gender identity with high prediction accuracy in each of the four groups based on connectivity signatures alone. The four normative gender groups were classified with accuracies ranging from 48% to 62% (exceeding chance level at 25%). These connectivity-based classification accuracies exceeded those obtained from a widely established behavioral instrument for gender identity. Using canonical correlation analyses, functional brain measurements and questionnaire data were then integrated to delineate nine canonical vectors (i.e., brain-gender axes), providing a multilevel window into the conventional sex dichotomy. Our dimensional gender perspective captures four distinguishable brain phenotypes for gender identity, advocating a biologically grounded reconceptualization of gender dimorphism. We hope to pave the way towards objective, data-driven diagnostic markers for gender identity and transgender, taking into account neurobiological and behavioral differences in an integrative modeling approach.
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Affiliation(s)
- Benjamin Clemens
- Department of Psychiatry, Psychotherapy and Psychosomatics, Faculty of Medicine, RWTH Aachen, 52074 Aachen, Germany.,Institute of Neuroscience and Medicine: JARA-Institute Brain Structure Function Relationship (INM 10), Wilhelm-Johnen-Straße 52425 Jülich, Germany
| | - Birgit Derntl
- Department of Psychiatry and Psychotherapy, University of Tübingen, 72076 Tübingen, Germany.,Werner Reichardt Center for Integrative Neuroscience (CIN), University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany.,LEAD Research Network, Walter-Simon-Straße 12, 72072 Tübingen, Germany
| | - Elke Smith
- Department of Psychiatry, Psychotherapy and Psychosomatics, Faculty of Medicine, RWTH Aachen, 52074 Aachen, Germany.,Department of Psychology, Biological Psychology, University of Cologne, Bernhard-Feilchenfeld-Str. 11, 50969 Cologne, Germany
| | - Jessica Junger
- Department of Psychiatry, Psychotherapy and Psychosomatics, Faculty of Medicine, RWTH Aachen, 52074 Aachen, Germany.,Institute of Neuroscience and Medicine: JARA-Institute Brain Structure Function Relationship (INM 10), Wilhelm-Johnen-Straße 52425 Jülich, Germany
| | - Josef Neulen
- Department of Gynecological Endocrinology and Reproductive Medicine, Faculty of Medicine, RWTH Aachen University, 52074 Aachen, Germany
| | - Gianluca Mingoia
- Interdisciplinary Center for Clinical Research (IZKF), RWTH Aachen University, Faculty of Medicine, Pauwelsstrasse 30, 52074 Aachen, Germany
| | - Frank Schneider
- Institute of Neuroscience and Medicine: JARA-Institute Brain Structure Function Relationship (INM 10), Wilhelm-Johnen-Straße 52425 Jülich, Germany.,University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Moorenstrasse 5, 40225 Düsseldorf, Germany
| | - Ted Abel
- Department of Biology, University of Pennsylvania, 433 South University Avenue, Philadelphia, PA 19104, United States.,Department of Neuroscience & Pharmacology, Iowa Neuroscience Institute, Carver College of Medicine, University of Iowa, 51 Newton Road 5-660 Bowen Science Building, Iowa City, IA 52242, United States
| | - Danilo Bzdok
- Department of Psychiatry, Psychotherapy and Psychosomatics, Faculty of Medicine, RWTH Aachen, 52074 Aachen, Germany.,Institute of Neuroscience and Medicine: JARA-Institute Brain Structure Function Relationship (INM 10), Wilhelm-Johnen-Straße 52425 Jülich, Germany.,Parietal Team, INRIA/Neurospin Saclay, 1 rue Honoré d'Estienne d'Orves, Campus de l'École Polytechnique, 91120 Palaiseau, France.,Department of Biomedical Engineering, Faculty of Medicine, McGill University, 3775, rue University Montréal, QC H3A 2B4, Canada.,Montreal Institute for Learning Algorithms (MILA), 6666 St-Urbain, #200 Montreal, QC H2S 3H1, Canada
| | - Ute Habel
- Department of Psychiatry, Psychotherapy and Psychosomatics, Faculty of Medicine, RWTH Aachen, 52074 Aachen, Germany.,Institute of Neuroscience and Medicine: JARA-Institute Brain Structure Function Relationship (INM 10), Wilhelm-Johnen-Straße 52425 Jülich, Germany
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31
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Peper JS, Burke SM, Wierenga LM. Sex differences and brain development during puberty and adolescence. HANDBOOK OF CLINICAL NEUROLOGY 2020; 175:25-54. [PMID: 33008529 DOI: 10.1016/b978-0-444-64123-6.00003-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Sex differences in behavior, and whether these behavioral differences are related to sex differences in brain development, has been a longstanding topic of debate. Presumably, sex differences can provide critically important leads for explaining the etiology of various illnesses that show (i) large sex differences in prevalence and (ii) have an origin before or during adolescence. The general aim of this chapter is to provide an overview of scientific studies on sex differences in normative brain and behavioral development across puberty and adolescence, including the (sex) hormone-driven transition phase of puberty. Moreover, we describe the literature on brain and behavioral development in gender dysphoria, a severe and persistent incongruence between the self-identified gender and the assigned sex at birth. From the literature it becomes clear there is evidence for a specific link between pubertal maturation and developmental changes in arousal, motivation, and emotion. However, this link is rather similar between boys and girls. Moreover, although there is substantial evidence for sex differences in mean brain structure, these have not always been linked to sex differences in behavior, cognition, or psychopathology. Furthermore, there is little evidence for sex differences in brain development and thus, studies so far have been unable to explain sex differences in cognition. Suggestions for future research and methodologic considerations are provided.
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Affiliation(s)
- Jiska S Peper
- Department of Psychology, Leiden University, Leiden, The Netherlands.
| | - Sarah M Burke
- Department of Psychology, Leiden University, Leiden, The Netherlands
| | - Lara M Wierenga
- Department of Psychology, Leiden University, Leiden, The Netherlands
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32
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Majid DSA, Burke SM, Manzouri A, Moody TD, Dhejne C, Feusner JD, Savic I. Neural Systems for Own-body Processing Align with Gender Identity Rather Than Birth-assigned Sex. Cereb Cortex 2019; 30:2897-2909. [PMID: 31813993 DOI: 10.1093/cercor/bhz282] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 10/04/2019] [Indexed: 01/18/2023] Open
Abstract
Gender identity is a core aspect of self-identity and is usually congruent with birth-assigned sex and own body sex-perception. The neuronal circuits underlying gender identity are unknown, but greater awareness of transgenderism has sparked interest in studying these circuits. We did this by comparing brain activation and connectivity in transgender individuals (for whom gender identity and birth-assigned sex are incongruent) with that in cisgender controls (for whom they are congruent) when performing a body self-identification task during functional magnetic resonance imaging. Thirty transgender and 30 cisgender participants viewed images of their own bodies and bodies morphed in sex toward or opposite to birth-assigned sex, rating each image to the degree they identified with it. While controls identified with images of themselves, transgender individuals identified with images morphed "opposite" to their birth-assigned sex. After covarying out the effect of self-similarity ratings, both groups activated similar self- and body-processing systems when viewing bodies that aligned with their gender identity rather than birth-assigned sex. Additionally, transgender participants had greater limbic involvement when viewing ambiguous, androgynous images of themselves morphed toward their gender identity. These results shed light on underlying self-processing networks specific to gender identity and uncover additional involvement of emotional processing in transgender individuals.
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Affiliation(s)
- D S Adnan Majid
- Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Sarah M Burke
- Department of Developmental and Educational Psychology, Leiden University, 2311 EZ Leiden, The Netherlands.,Department of Women's and Children's Health, Karolinska Institutet, 171 77 Solna, Stockholm, Sweden
| | | | - Teena D Moody
- Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Cecilia Dhejne
- Department of Medicine, Karolinska University Hospital, Huddinge, Karolinska Institutet, 171 76 Solna, Stockholm, Sweden
| | - Jamie D Feusner
- Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Ivanka Savic
- Department of Women's and Children's Health, Karolinska Institutet, 171 77 Solna, Stockholm, Sweden.,Department of Neurology, University of California Los Angeles, Los Angeles, CA 90095, USA
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33
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A New Theory of Gender Dysphoria Incorporating the Distress, Social Behavioral, and Body-Ownership Networks. eNeuro 2019; 6:ENEURO.0183-19.2019. [PMID: 31792116 PMCID: PMC6911960 DOI: 10.1523/eneuro.0183-19.2019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 10/29/2019] [Accepted: 11/04/2019] [Indexed: 12/16/2022] Open
Abstract
When postmortem studies related to transgender individuals were first published, little was known about the function of the various identified nuclei. Now, over 2 decades later, significant progress has been made associating function with specific brain regions, as well as in identifying networks associated with groups of behaviors. However, much of this progress has not been integrated into the general conceptualization of gender dysphoria in humans. When postmortem studies related to transgender individuals were first published, little was known about the function of the various identified nuclei. Now, over 2 decades later, significant progress has been made associating function with specific brain regions, as well as in identifying networks associated with groups of behaviors. However, much of this progress has not been integrated into the general conceptualization of gender dysphoria in humans. I hypothesize that in individuals with gender dysphoria, the aspects of chronic distress, gender atypical behavior, and incongruence between perception of gender identity and external primary sex characteristics are all directly related to functional differences in associated brain networks. I evaluated previously published neuroscience data related to these aspects and the associated functional networks, along with other relevant information. I find that the brain networks that give individuals their ownership of body parts, that influence gender typical behavior, and that are involved in chronic distress are different in individuals with and without gender dysphoria, leading to a new theory—that gender dysphoria is a sensory perception condition, an alteration in the sense of gender influenced by the reflexive behavioral responses associated with each of these networks. This theory builds upon previous work that supports the relevance of the body-ownership network and that questions the relevance of cerebral sexual dimorphism in regard to gender dysphoria. However, my theory uses a hierarchical executive function model to incorporate multiple reflexive factors (body ownership, gender typical/atypical behavior, and chronic distress) with the cognitive, reflective process of gender identity.
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34
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Trait and state patterns of basolateral amygdala connectivity at rest are related to endogenous testosterone and aggression in healthy young women. Brain Imaging Behav 2019; 13:564-576. [PMID: 29744800 DOI: 10.1007/s11682-018-9884-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The steroid hormone testosterone (T) has been suggested to influence reactive aggression upon its action on the basolateral amygdala (BLA), a key brain region for threat detection. However, it is unclear whether T modulates resting-state functional connectivity (rsFC) of the BLA, and whether this predicts subsequent aggressive behavior. Aggressive interactions themselves, which often induce changes in T concentrations, could further alter BLA rsFC, but this too remains untested. Here we investigated the effect of endogenous T on rsFC of the BLA at baseline as well as after an aggressive encounter, and whether this was related to behavioral aggression in healthy young women (n = 39). Pre-scan T was negatively correlated with basal rsFC between BLA and left superior temporal gyrus (STG; p < .001, p < .05 Family-Wise Error [FWE] cluster-level corrected), which in turn was associated with increased aggression (r = .37, p = .020). BLA-STG coupling at rest might thus underlie hostile readiness in low-T women. In addition, connectivity between the BLA and the right superior parietal lobule (SPL), a brain region involved in higher-order perceptual processes, was reduced in aggressive participants (p < .001, p < .05 FWE cluster-level corrected). On the other hand, post-task increases in rsFC between BLA and medial orbitofrontal cortex (mOFC) were linked to reduced aggression (r = -.36, p = .023), consistent with the established notion that the mOFC regulates amygdala activity in order to curb aggressive impulses. Finally, competition-induced changes in T were associated with increased coupling between the BLA and the right lateral OFC (p < .001, p < .05 FWE cluster-level corrected), but this effect was unrelated to aggression. We thus identified connectivity patterns that prospectively predict aggression in women, and showed how aggressive interactions in turn impact these neural systems.
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35
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Kilpatrick LA, Holmberg M, Manzouri A, Savic I. Cross sex hormone treatment is linked with a reversal of cerebral patterns associated with gender dysphoria to the baseline of cisgender controls. Eur J Neurosci 2019; 50:3269-3281. [PMID: 30991464 DOI: 10.1111/ejn.14420] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 03/27/2019] [Accepted: 04/03/2019] [Indexed: 12/22/2022]
Abstract
Transgender persons experience incongruence between their gender identity and birth-assigned sex. The resulting gender dysphoria (GD), is frequently treated with cross-sex hormones. However, very little is known about how this treatment affects the brain of individuals with GD, nor do we know the neurobiology of GD. We recently suggested that disconnection of fronto-parietal networks involved in own-body self-referential processing could be a plausible mechanism, and that the anatomical correlate could be a thickening of the mesial prefrontal and precuneus cortex, which is unrelated to sex. Here, we investigate how cross-sex hormone treatment affects cerebral tissue in persons with GD, and how potential changes are related to self-body perception. Longitudinal MRI measurements of cortical thickness (Cth) were carried out in 40 transgender men (TrM), 24 transgender women (TrW) and 19 controls. Cth increased in the mesial temporal and insular cortices with testosterone treatment in TrM, whereas anti-androgen and oestrogen treatment in TrW caused widespread cortical thinning. However, after correction for treatment-related changes in total grey and white matter volumes (increase with testosterone; decrease with anti-androgen and oestrogen), significant Cth decreases were observed in the mesial prefrontal and parietal cortices, in both TrM and TrW (vs. controls) - regions showing greater pre-treatment Cth than in controls. The own body - self congruence ratings increased with treatment, and correlated with a left parietal cortical thinning. These data confirm our hypothesis that GD may be associated with specific anatomical features in own-body/self-processing circuits that reverse to the pattern of cisgender controls after cross-sex hormone treatment.
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Affiliation(s)
- Lisa A Kilpatrick
- Center for Neurobiology of Stress and Resilience, Department of Medicine, Division of Digestive Diseases, University of California, Los Angeles, California, USA
| | - Mats Holmberg
- Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden.,ANOVA, Center of Expertise in Andrology, Sexual Medicine, and Transgender Medicine, Karolinska University Hospital, Stockholm, Sweden.,Department of Medicine/Huddinge, Karolinska Institutet, Stockholm, Sweden
| | - Amirhosein Manzouri
- Department of Women's and Children's Health, Karolinska Institutet and University Hospital, Stockholm, Sweden
| | - Ivanka Savic
- Department of Women's and Children's Health, Karolinska Institutet and University Hospital, Stockholm, Sweden.,Department of Neurology, University of California Los Angeles, Los Angeles, California, USA
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36
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Nguyen HB, Loughead J, Lipner E, Hantsoo L, Kornfield SL, Epperson CN. What has sex got to do with it? The role of hormones in the transgender brain. Neuropsychopharmacology 2019; 44:22-37. [PMID: 30082887 PMCID: PMC6235900 DOI: 10.1038/s41386-018-0140-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Revised: 05/23/2018] [Accepted: 06/21/2018] [Indexed: 01/04/2023]
Abstract
Sex differences and hormonal effects in presumed cisgender individuals have been well-studied and support the concept of a mosaic of both male and female "characteristics" in any given brain. Gonadal steroid increases and fluctuations during peri-puberty and across the reproductive lifespan influence the brain structure and function programmed by testosterone and estradiol exposures in utero. While it is becoming increasingly common for transgender and gender non-binary individuals to block their transition to puberty and/or use gender-affirming hormone therapy (GAHT) to obtain their desired gender phenotype, little is known about the impact of these manipulations on brain structure and function. Using sex differences and the effects of reproductive hormones in cisgender individuals as the backdrop, we summarize here the existing nascent neuroimaging and behavioral literature focusing on potential brain and cognitive differences in transgender individuals at baseline and after GAHT. Research in this area has the potential to inform our understanding of the developmental origins of gender identity and sex difference in response to gonadal steroid manipulations, but care is needed in our research questions and methods to not further stigmatize sex and gender minorities.
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Affiliation(s)
- Hillary B Nguyen
- School of Arts and Sciences, Philadelphia, PA, USA
- Penn PROMOTES Research on Sex and Gender in Health, University of Pennsylvania, Philadelphia, PA, USA
- Department of Psychiatry, Philadelphia, PA, USA
| | | | - Emily Lipner
- School of Arts and Sciences, Philadelphia, PA, USA
- Penn PROMOTES Research on Sex and Gender in Health, University of Pennsylvania, Philadelphia, PA, USA
| | | | | | - C Neill Epperson
- School of Arts and Sciences, Philadelphia, PA, USA.
- Penn PROMOTES Research on Sex and Gender in Health, University of Pennsylvania, Philadelphia, PA, USA.
- Department of Psychiatry, Philadelphia, PA, USA.
- Department of Obstetrics and Gynecology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.
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37
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Burke SM, Majid DSA, Manzouri AH, Moody T, Feusner JD, Savic I. Sex differences in own and other body perception. Hum Brain Mapp 2018; 40:474-488. [PMID: 30430680 PMCID: PMC6587810 DOI: 10.1002/hbm.24388] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 08/07/2018] [Accepted: 08/28/2018] [Indexed: 12/30/2022] Open
Abstract
Own body perception, and differentiating and comparing one's body to another person's body, are common cognitive functions that have relevance for self‐identity and social interactions. In several psychiatric conditions, including anorexia nervosa, body dysmorphic disorder, gender dysphoria, and autism spectrum disorder, self and own body perception, as well as aspects of social communication are disturbed. Despite most of these conditions having skewed prevalence sex ratios, little is known about whether the neural basis of own body perception differs between the sexes. We addressed this question by investigating brain activation using functional magnetic resonance imaging during a Body Perception task in 15 male and 15 female healthy participants. Participants viewed their own body, bodies of same‐sex, or opposite‐sex other people, and rated the degree that they appeared like themselves. We found that men and women did not differ in the pattern of brain activation during own body perception compared to a scrambled control image. However, when viewing images of other bodies of same‐sex or opposite‐sex, men showed significantly stronger activations in attention‐related and reward‐related brain regions, whereas women engaged stronger activations in striatal, medial‐prefrontal, and insular cortices, when viewing the own body compared to other images of the opposite sex. It is possible that other body images, particularly of the opposite sex, may be of greater salience for men, whereas images of own bodies may be more salient for women. These observations provide tentative neurobiological correlates to why women may be more vulnerable than men to conditions involving own body perception.
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Affiliation(s)
- Sarah M Burke
- Brain & Development Research Centre, Department of Developmental and Educational Psychology, Leiden University, Leiden, The Netherlands.,Department of Women's and Children's Health, Karolinska Institute and University Hospital, Stockholm, Sweden
| | - D S Adnan Majid
- Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, California
| | - Amir H Manzouri
- Department of Women's and Children's Health, Karolinska Institute and University Hospital, Stockholm, Sweden.,Department of Psychology, Stockholm University, Stockholm, Sweden
| | - Teena Moody
- Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, California
| | - Jamie D Feusner
- Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, California
| | - Ivanka Savic
- Department of Women's and Children's Health, Karolinska Institute and University Hospital, Stockholm, Sweden.,Department of Neurology, University of California Los Angeles, Los Angeles, California
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38
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Nguyen HB, Chavez AM, Lipner E, Hantsoo L, Kornfield SL, Davies RD, Epperson CN. Gender-Affirming Hormone Use in Transgender Individuals: Impact on Behavioral Health and Cognition. Curr Psychiatry Rep 2018; 20:110. [PMID: 30306351 PMCID: PMC6354936 DOI: 10.1007/s11920-018-0973-0] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
PURPOSE OF REVIEW With increasing numbers of transgender and gender non-binary individuals presenting for care, knowing how to elucidate the mental health and cognitive outcomes of gender-affirming hormone therapy (GAHT) is necessary. This article reviews the present literature covering GAHT effects on mood, behavioral health, and cognition in these individuals and offers research priorities to address knowledge gaps. RECENT FINDINGS Although there are some conflicting data, GAHT overwhelmingly seems to have positive psychological effects in both adolescents and adults. Research tends to support that GAHT reduces symptoms of anxiety and depression, lowers perceived and social distress, and improves quality of life and self-esteem in both male-to-female and female-to-male transgender individuals. Clinically, prescribing GAHT can help with gender dysphoria-related mental distress. Thus, timely hormonal intervention represents a crucial tool for improving behavioral wellness in transgender individuals, though effects on cognitive processes fundamental for daily living are unknown. Future research should prioritize better understanding of how GAHT may affect executive functioning.
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Affiliation(s)
- Hillary B. Nguyen
- School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA, USA,Penn PROMOTES Research on Sex and Gender in Health, University of Pennsylvania, Philadelphia, PA, USA,Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA,Department of Psychiatry, University of Colorado School of Medicine-Anschutz Medical Campus, 13001 E 17th Place, MS F546, Aurora, CO 80045, USA
| | - Alexis M. Chavez
- Department of Psychiatry, University of Colorado School of Medicine-Anschutz Medical Campus, 13001 E 17th Place, MS F546, Aurora, CO 80045, USA
| | - Emily Lipner
- Penn PROMOTES Research on Sex and Gender in Health, University of Pennsylvania, Philadelphia, PA, USA,Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Liisa Hantsoo
- Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Sara L. Kornfield
- Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Robert D. Davies
- Department of Psychiatry, University of Colorado School of Medicine-Anschutz Medical Campus, 13001 E 17th Place, MS F546, Aurora, CO 80045, USA
| | - C. Neill Epperson
- Penn PROMOTES Research on Sex and Gender in Health, University of Pennsylvania, Philadelphia, PA, USA,Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA,Department of Psychiatry, University of Colorado School of Medicine-Anschutz Medical Campus, 13001 E 17th Place, MS F546, Aurora, CO 80045, USA
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39
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Manzouri A, Savic I. Cerebral sex dimorphism and sexual orientation. Hum Brain Mapp 2018; 39:1175-1186. [PMID: 29227002 PMCID: PMC6866632 DOI: 10.1002/hbm.23908] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2017] [Revised: 11/29/2017] [Accepted: 11/29/2017] [Indexed: 11/08/2022] Open
Abstract
The neurobiology of sexual orientation is frequently discussed in terms of cerebral sex dimorphism (defining both functional and structural sex differences). Yet, the information about possible cerebral differences between sex-matched homo and heterosexual persons is limited, particularly among women. In this multimodal MRI study, we addressed these issues by investigating possible cerebral differences between homo and heterosexual persons, and by asking whether there is any sex difference in this aspect. Measurements of cortical thickness (Cth), subcortical volumes, and functional and structural resting-state connections among 40 heterosexual males (HeM) and 40 heterosexual females (HeF) were compared with those of 30 homosexual males (HoM) and 30 homosexual females (HoF). Congruent with previous reports, sex differences were detected in heterosexual controls with regard to fractional anisotropy (FA), Cth, and several subcortical volumes. Homosexual groups did not display any sex differences in FA values. Furthermore, their functional connectivity was significantly less pronounced in the mesial prefrontal and precuneus regions. In these two particular regions, HoM also displayed thicker cerebral cortex than other groups, whereas HoF did not differ from HeF. In addition, in HoM the parietal Cth showed "sex-reversed" values, not observed in HoF. Homosexual orientation seems associated with a less pronounced sexual differentiation of white matter tracts and a less pronounced functional connectivity of the self-referential networks compared to heterosexual orientation. Analyses of Cth suggest that male and female homosexuality are not simple analogues of each other and that differences from heterosexual controls are more pronounced in HoM.
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Affiliation(s)
- Amirhossein Manzouri
- Department of Women's and Children's Health, and Neurology ClinicKarolinska Institutet and HospitalStickholmSE‐171 76Sweden
| | - Ivanka Savic
- Department of Women's and Children's Health, and Neurology ClinicKarolinska Institutet and HospitalStickholmSE‐171 76Sweden
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40
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Burke SM, Manzouri AH, Savic I. Structural connections in the brain in relation to gender identity and sexual orientation. Sci Rep 2017; 7:17954. [PMID: 29263327 PMCID: PMC5738422 DOI: 10.1038/s41598-017-17352-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 11/23/2017] [Indexed: 12/22/2022] Open
Abstract
Both transgenderism and homosexuality are facets of human biology, believed to derive from different sexual differentiation of the brain. The two phenomena are, however, fundamentally unalike, despite an increased prevalence of homosexuality among transgender populations. Transgenderism is associated with strong feelings of incongruence between one's physical sex and experienced gender, not reported in homosexual persons. The present study searches to find neural correlates for the respective conditions, using fractional anisotropy (FA) as a measure of white matter connections that has consistently shown sex differences. We compared FA in 40 transgender men (female birth-assigned sex) and 27 transgender women (male birth-assigned sex), with both homosexual (29 male, 30 female) and heterosexual (40 male, 40 female) cisgender controls. Previously reported sex differences in FA were reproduced in cis-heterosexual groups, but were not found among the cis-homosexual groups. After controlling for sexual orientation, the transgender groups showed sex-typical FA-values. The only exception was the right inferior fronto-occipital tract, connecting parietal and frontal brain areas that mediate own body perception. Our findings suggest that the neuroanatomical signature of transgenderism is related to brain areas processing the perception of self and body ownership, whereas homosexuality seems to be associated with less cerebral sexual differentiation.
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Affiliation(s)
- Sarah M Burke
- Brain & Development Research Centre, Department of Developmental and Educational Psychology, Leiden University, Leiden, The Netherlands.
- Department of Women's and Children's Health, Karolinska Institute and University Hospital, Stockholm, Sweden.
| | - Amir H Manzouri
- Stressmotagningen, S:t Göransgatan 84, 112 38, Stockholm, Sweden
| | - Ivanka Savic
- Department of Women's and Children's Health, Karolinska Institute and University Hospital, Stockholm, Sweden
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41
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Nota NM, Kreukels BPC, den Heijer M, Veltman DJ, Cohen-Kettenis PT, Burke SM, Bakker J. Brain functional connectivity patterns in children and adolescents with gender dysphoria: Sex-atypical or not? Psychoneuroendocrinology 2017; 86:187-195. [PMID: 28972892 DOI: 10.1016/j.psyneuen.2017.09.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 09/14/2017] [Indexed: 01/01/2023]
Abstract
Various previous studies have reported that brains of people diagnosed with gender dysphoria (GD) show sex-atypical features. In addition, recent functional magnetic resonance imaging studies found that several brain resting-state networks (RSNs) in adults with GD show functional connectivity (FC) patterns that are not sex-atypical, but specific for GD. In the current study we examined whether FC patterns are also altered in prepubertal children and adolescents with GD in comparison with non-gender dysphoric peers. We investigated FC patterns within RSNs that were previously examined in adults: visual networks (VNs), sensorimotor networks (SMNs), default mode network (DMN) and salience network. Thirty-one children (18 birth assigned males; 13 birth assigned females) and 40 adolescents with GD (19 birth assigned males or transgirls; 21 birth assigned females or transboys), and 39 cisgender children (21 boys; 18 girls) and 41 cisgender adolescents (20 boys; 21 girls) participated. We used independent component analysis to obtain the network maps of interest and compared these across groups. Within one of the three VNs (VN-I), adolescent transgirls showed stronger FC in the right cerebellum compared with all other adolescent groups. Sex differences in FC between the cisgender adolescent groups were observed in the right supplementary motor area within one of the two SMNs (SMN-II; girls>boys) and the right posterior cingulate gyrus within the posterior DMN (boys>girls). Within these networks adolescent transgirls showed FC patterns similar to their experienced gender (female). Also adolescent transboys showed a FC pattern similar to their experienced gender (male), but within the SMN-II only. The prepubertal children did not show any group differences in FC, suggesting that these emerge with aging and during puberty. Our findings provide evidence for the existence of both GD-specific and sex-atypical FC patterns in adolescents with GD.
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Affiliation(s)
- Nienke M Nota
- Department of Internal Medicine, Division of Endocrinology, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Baudewijntje P C Kreukels
- Department of Medical Psychology, Neuroscience Campus Amsterdam, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands.
| | - Martin den Heijer
- Department of Internal Medicine, Division of Endocrinology, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Dick J Veltman
- Department of Psychiatry, Neuroscience Campus Amsterdam, VU University Medical, Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Peggy T Cohen-Kettenis
- Department of Medical Psychology, Neuroscience Campus Amsterdam, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Sarah M Burke
- Department of Developmental and Educational Psychology, Leiden University, Pieter de la Court Gebouw, Wassenaarseweg 52, 2333 AK Leiden, The Netherlands
| | - Julie Bakker
- Department of Medical Psychology, Neuroscience Campus Amsterdam, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands; Neuroendocrinology, GIGA Neurosciences, University of Liège, Avenue Hippocrate, 15, 4000 Liège, Belgium
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