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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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2
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Thurston LT, Skorska MN, Lobaugh NJ, Zucker KJ, Chakravarty MM, Lai MC, Chavez S, VanderLaan DP. White matter microstructure in transmasculine and cisgender adolescents: A multiparametric and multivariate study. PLoS One 2024; 19:e0300139. [PMID: 38470896 DOI: 10.1371/journal.pone.0300139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Accepted: 02/21/2024] [Indexed: 03/14/2024] Open
Abstract
Adolescence is a sensitive developmental period for neural sex/gender differentiation. The present study used multiparametric mapping to better characterize adolescent white matter (WM) microstructure. WM microstructure was investigated using diffusion tensor indices (fractional anisotropy; mean, radial, and axial diffusivity [AD]) and quantitative T1 relaxometry (T1) in hormone therapy naïve adolescent cisgender girls, cisgender boys, and transgender boys (i.e., assigned female at birth and diagnosed with gender dysphoria). Diffusion indices were first analyzed for group differences using tract-based spatial statistics, which revealed a group difference in AD. Thus, two multiparametric and multivariate analyses assessed AD in conjunction with T1 relaxation time, and with respect to developmental proxy variables (i.e., age, serum estradiol, pubertal development, sexual attraction) thought to be relevant to adolescent brain development. The multivariate analyses showed a shared pattern between AD and T1 such that higher AD was associated with longer T1, and AD and T1 strongly related to all five developmental variables in cisgender boys (10 significant correlations, r range: 0.21-0.73). There were fewer significant correlations between the brain and developmental variables in cisgender girls (three correlations, r range: -0.54-0.54) and transgender boys (two correlations, r range: -0.59-0.77). Specifically, AD related to direction of sexual attraction (i.e., gynephilia, androphilia) in all groups, and T1 related to estradiol inversely in cisgender boys compared with transgender boys. These brain patterns may be indicative of less myelination and tissue density in cisgender boys, which corroborates other reports of protracted WM development in cisgender boys. Further, these findings highlight the importance of considering developmental trajectory when assessing the subtleties of neural structure associated with variations in sex, gender, and sexual attraction.
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Affiliation(s)
- Lindsey T Thurston
- Department of Psychology, University of Toronto Mississauga, Mississauga, Ontario, Canada
| | - Malvina N Skorska
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Nancy J Lobaugh
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
- Division of Neurology, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Kenneth J Zucker
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - M Mallar Chakravarty
- Cerebral Imaging Centre, Douglas Mental Health University Institute, Montreal, Ontario, Canada
| | - Meng-Chuan Lai
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
- Department of Psychiatry, The Hospital for Sick Children, Toronto, Ontario, Canada
- Autism Research Centre, Department of Psychiatry, University of Cambridge, Cambridge, United Kingdom
| | - Sofia Chavez
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Doug P VanderLaan
- Department of Psychology, University of Toronto Mississauga, Mississauga, Ontario, Canada
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
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Lafta MS, Mwinyi J, Affatato O, Rukh G, Dang J, Andersson G, Schiöth HB. Exploring sex differences: insights into gene expression, neuroanatomy, neurochemistry, cognition, and pathology. Front Neurosci 2024; 18:1340108. [PMID: 38449735 PMCID: PMC10915038 DOI: 10.3389/fnins.2024.1340108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 02/09/2024] [Indexed: 03/08/2024] Open
Abstract
Increased knowledge about sex differences is important for development of individualized treatments against many diseases as well as understanding behavioral and pathological differences. This review summarizes sex chromosome effects on gene expression, epigenetics, and hormones in relation to the brain. We explore neuroanatomy, neurochemistry, cognition, and brain pathology aiming to explain the current state of the art. While some domains exhibit strong differences, others reveal subtle differences whose overall significance warrants clarification. We hope that the current review increases awareness and serves as a basis for the planning of future studies that consider both sexes equally regarding similarities and differences.
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Affiliation(s)
- Muataz S. Lafta
- Department of Surgical Sciences, Functional Pharmacology and Neuroscience, Uppsala University, Uppsala, Sweden
| | - Jessica Mwinyi
- Department of Surgical Sciences, Functional Pharmacology and Neuroscience, Uppsala University, Uppsala, Sweden
- Centre for Women’s Mental Health, Uppsala University, Uppsala, Sweden
| | - Oreste Affatato
- Department of Surgical Sciences, Functional Pharmacology and Neuroscience, Uppsala University, Uppsala, Sweden
- Centre for Women’s Mental Health, Uppsala University, Uppsala, Sweden
| | - Gull Rukh
- Department of Surgical Sciences, Functional Pharmacology and Neuroscience, Uppsala University, Uppsala, Sweden
| | - Junhua Dang
- Department of Surgical Sciences, Functional Pharmacology and Neuroscience, Uppsala University, Uppsala, Sweden
| | - Gerhard Andersson
- Department of Behavioural Sciences and Learning, Linköping University, Linköping, Sweden
- Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden
| | - Helgi B. Schiöth
- Department of Surgical Sciences, Functional Pharmacology and Neuroscience, Uppsala University, Uppsala, Sweden
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Almås EM, Benestad EEP, Bolstad SH, Karlsen TI, Giami A. Gender Identity Orientation and Sexual Activity-A Survey among Transgender and Gender-Diverse (TGD) Individuals in Norway. Healthcare (Basel) 2024; 12:482. [PMID: 38391857 PMCID: PMC10888209 DOI: 10.3390/healthcare12040482] [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: 12/07/2023] [Revised: 02/08/2024] [Accepted: 02/13/2024] [Indexed: 02/24/2024] Open
Abstract
BACKGROUND The understanding and conceptualizing of gender and sexuality are continuously negotiated between individuals and cultures. Recently, new gender identity orientations have emerged, fighting pathologization and establishing new spaces and options for being sexually active gendered beings. OBJECTIVE To investigate variations in sexual activities across different gender identity orientations. METHOD A questionnaire used in France was adapted to the Norwegian context and implemented in this study. The participants were recruited through therapists, TGD organizations, and social media. RESULTS A total of 538 individuals responded to the questionnaire, of which 336 provided a written description of their gender identity. Based on an analysis of the degree of male gender identity orientation, the degree of female gender identity orientation, and the degree of nonbinary gender identity orientation, three clusters appeared and were used in the analyses of sexual activities and preferences. CONCLUSIONS Some findings could be attributed to lingering aspects of traditional gender roles, while others may be indicative of sexual expression stemming from societal acceptance of gender diversity and new identity orientations.
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Affiliation(s)
- Elsa Mari Almås
- Department of Psychosocial Health, University of Agder, 4604 Kristiansand, Norway
| | | | - Silje-Håvard Bolstad
- Department of Psychosocial Health, University of Agder, 4604 Kristiansand, Norway
| | - Tor-Ivar Karlsen
- Department of Psychosocial Health, University of Agder, 4604 Kristiansand, Norway
| | - Alain Giami
- INSERM (National Institute of Health and Medical Research), 94807 Paris, France
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Arraiza Zabalegui M. After the trans brain: a critique of the neurobiological accounts of embodied trans* identities. HISTORY AND PHILOSOPHY OF THE LIFE SCIENCES 2024; 46:10. [PMID: 38305812 PMCID: PMC10837215 DOI: 10.1007/s40656-023-00602-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Accepted: 12/13/2023] [Indexed: 02/03/2024]
Abstract
This paper critically analyses three main neurobiological hypotheses on trans* identities: the neurobiological theory about the origin of gender dysphoria, the neurodevelopmental cortical hypothesis, and the alternative hypothesis of self-referential thinking and body perception. In this study I focus then the attention on three elements: the issue of (de)pathologisation, the idea of the trans brain, and the aetiology of trans* identities. While the neurobiological theory about the origin of gender dysphoria and the neurodevelopmental cortical hypothesis claim the existence of the trans brain, each offering its own neurobiological depiction, the hypothesis of self-referential thinking and body perception doesn't postulate a distinctive neurobiological trait for all trans* people. I problematize both portrayals of the trans brain departing from the findings and conceptualizations of the paradigm shifting brain mosaicism. Unlike the hypothesis of self-referential thinking and body perception that keeps the question of causation open, both the neurobiological theory about the origin of gender dysphoria and the neurodevelopmental cortical hypothesis situate the origin of trans* identities in the neurobiological domain. I challenge the biological deterministic framework in which this aetiology is inscribed from a dynamic processual entanglement perspective. Finally, concerning the issue of (de)pathologisation of trans* identities, an evolution can be seen in each of the hypothesis and among them, from the least to the most depathologising. However, I question their complete departure from a pathologising framework.
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Affiliation(s)
- Maite Arraiza Zabalegui
- Department of Philosophy, Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU), Donostia/San Sebastián, Spain.
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Cartier L, Guérin M, Saulnier F, Cotocea I, Mohammedi A, Moussaoui F, Kheloui S, Juster RP. Sex and gender correlates of sexually polymorphic cognition. Biol Sex Differ 2024; 15:3. [PMID: 38191503 PMCID: PMC10773055 DOI: 10.1186/s13293-023-00579-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 12/21/2023] [Indexed: 01/10/2024] Open
Abstract
BACKGROUND Sexually polymorphic cognition (SPC) results from the interaction between biological (birth-assigned sex (BAS), sex hormones) and socio-cultural (gender identity, gender roles, sexual orientation) factors. The literature remains quite mixed regarding the magnitude of the effects of these variables. This project used a battery of classic cognitive tests designed to assess the influence of sex hormones on cognitive performance. At the same time, we aimed to assess the inter-related and respective effects that BAS, sex hormones, and gender-related factors have on SPC. METHODS We recruited 222 adults who completed eight cognitive tasks that assessed a variety of cognitive domains during a 150-min session. Subgroups were separated based on gender identity and sexual orientation and recruited as follows: cisgender heterosexual men (n = 46), cisgender non-heterosexual men (n = 36), cisgender heterosexual women (n = 36), cisgender non-heterosexual women (n = 38), gender diverse (n = 66). Saliva samples were collected before, during, and after the test to assess testosterone, estradiol, progesterone, cortisol, and dehydroepiandrosterone. Psychosocial variables were derived from self-report questionnaires. RESULTS Cognitive performance reflects sex and gender differences that are partially consistent with the literature. Interestingly, biological factors seem to better explain differences in male-typed cognitive tasks (i.e., spatial), while psychosocial factors seem to better explain differences in female-typed cognitive tasks (i.e., verbal). CONCLUSION Our results establish a better comprehension of SPC over and above the effects of BAS as a binary variable. We highlight the importance of treating sex as a biological factor and gender as a socio-cultural factor together since they collectively influence SPC.
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Affiliation(s)
- Louis Cartier
- Center on Sex*Gender, Allostasis, and Resilience, Research Center of the Montreal Mental Health University Institute, 7331, Rue Hochelaga, Montreal, QC, H1N 3V2, Canada
- Department of Psychiatry and Addiction, University of Montreal, Montreal, QC, Canada
| | - Mina Guérin
- Center on Sex*Gender, Allostasis, and Resilience, Research Center of the Montreal Mental Health University Institute, 7331, Rue Hochelaga, Montreal, QC, H1N 3V2, Canada
- Department of Psychology, University of Montreal, Montreal, QC, Canada
| | - Fanny Saulnier
- Center on Sex*Gender, Allostasis, and Resilience, Research Center of the Montreal Mental Health University Institute, 7331, Rue Hochelaga, Montreal, QC, H1N 3V2, Canada
- Department of Psychiatry and Addiction, University of Montreal, Montreal, QC, Canada
| | - Ioana Cotocea
- Center on Sex*Gender, Allostasis, and Resilience, Research Center of the Montreal Mental Health University Institute, 7331, Rue Hochelaga, Montreal, QC, H1N 3V2, Canada
| | - Amine Mohammedi
- Center on Sex*Gender, Allostasis, and Resilience, Research Center of the Montreal Mental Health University Institute, 7331, Rue Hochelaga, Montreal, QC, H1N 3V2, Canada
- Department of Psychology, University of Montreal, Montreal, QC, Canada
| | - Fadila Moussaoui
- Center on Sex*Gender, Allostasis, and Resilience, Research Center of the Montreal Mental Health University Institute, 7331, Rue Hochelaga, Montreal, QC, H1N 3V2, Canada
- Department of Psychology, University of Montreal, Montreal, QC, Canada
| | - Sarah Kheloui
- School of Psychology, University of Ottawa, Ottawa, ON, Canada
| | - Robert-Paul Juster
- Center on Sex*Gender, Allostasis, and Resilience, Research Center of the Montreal Mental Health University Institute, 7331, Rue Hochelaga, Montreal, QC, H1N 3V2, Canada.
- Department of Psychiatry and Addiction, University of Montreal, Montreal, QC, Canada.
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7
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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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VanderLaan DP, Skorska MN, Peragine DE, Coome LA. Carving the Biodevelopment of Same-Sex Sexual Orientation at Its Joints. ARCHIVES OF SEXUAL BEHAVIOR 2023; 52:2939-2962. [PMID: 35960401 DOI: 10.1007/s10508-022-02360-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 05/30/2022] [Accepted: 06/04/2022] [Indexed: 06/15/2023]
Abstract
Sexual orientation is a core aspect of human experience and understanding its development is fundamental to psychology as a scientific discipline. Biological perspectives have played an important role in uncovering the processes that contribute to sexual orientation development. Research in this field has relied on a variety of populations, including community, clinical, and cross-cultural samples, and has commonly focused on female gynephilia (i.e., female sexual attraction to adult females) and male androphilia (i.e., male sexual attraction to adult males). Genetic, hormonal, and immunological processes all appear to influence sexual orientation. Consistent with biological perspectives, there are sexual orientation differences in brain development and evidence indicates that similar biological influences apply across cultures. An outstanding question in the field is whether the hypothesized biological influences are all part of the same process or represent different developmental pathways leading to same-sex sexual orientation. Some studies indicate that same-sex sexually oriented people can be divided into subgroups who likely experienced different biological influences. Consideration of gender expression in addition to sexual orientation might help delineate such subgroups. Thus, future research on the possible existence of such subgroups could prove to be valuable for uncovering the biological development of sexual orientation. Recommendations for such future research are discussed.
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Affiliation(s)
- Doug P VanderLaan
- Department of Psychology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON, L5L 1C6, Canada.
- Child and Youth Psychiatry, Centre for Addiction and Mental Health, Toronto, ON, Canada.
| | - Malvina N Skorska
- Child and Youth Psychiatry, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Diana E Peragine
- Department of Psychology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON, L5L 1C6, Canada
| | - Lindsay A Coome
- Department of Psychology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON, L5L 1C6, Canada
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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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10
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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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11
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Iwamoto SJ, Defreyne J, Kaoutzanis C, Davies RD, Moreau KL, Rothman MS. Gender-affirming hormone therapy, mental health, and surgical considerations for aging transgender and gender diverse adults. Ther Adv Endocrinol Metab 2023; 14:20420188231166494. [PMID: 37113210 PMCID: PMC10126651 DOI: 10.1177/20420188231166494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Accepted: 03/13/2023] [Indexed: 04/29/2023] Open
Abstract
As the transgender and gender diverse (TGD) population ages, more transfeminine and transmasculine individuals present to clinic to initiate or continue their gender-affirming care at older ages. Currently available guidelines on gender-affirming care are excellent resources for the provision of gender-affirming hormone therapy (GAHT), primary care, surgery, and mental health care but are limited in their scope as to whether recommendations require tailoring to older TGD adults. Data that inform guideline-recommended management considerations, while informative and increasingly evidence-based, mainly come from studies of younger TGD populations. Whether results from these studies, and therefore recommendations, can or should be extrapolated to aging TGD adults remains to be determined. In this perspective review, we acknowledge the lack of data in older TGD adults and discuss considerations for evaluating cardiovascular disease, hormone-sensitive cancers, bone health and cognitive health, gender-affirming surgery, and mental health in the older TGD population on GAHT.
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Affiliation(s)
| | - Justine Defreyne
- Department of Endocrinology, Ghent University Hospital, Ghent, Belgium
| | - Christodoulos Kaoutzanis
- Division of Plastic and Reconstructive Surgery, Department of Surgery, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- UCHealth Integrated Transgender Program – Anschutz Medical Campus, Aurora, CO, USA
| | - Robert D. Davies
- Department of Psychiatry, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- CUMedicine LGBTQ Mental Health Clinic, University of Colorado Hospital, Aurora, CO, USA
- UCHealth Integrated Transgender Program – Anschutz Medical Campus, Aurora, CO, USA
| | - Kerrie L. Moreau
- Division of Geriatric Medicine, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Eastern Colorado Geriatric Research Education and Clinical Center, Rocky Mountain Regional VA Medical Center, Aurora, CO, USA
| | - Micol S. Rothman
- Division of Endocrinology, Metabolism and Diabetes, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- UCHealth Integrated Transgender Program – Anschutz Medical Campus, Aurora, CO, USA
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12
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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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13
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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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14
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Hanlon CA, McCalley DM. Sex/Gender as a Factor That Influences Transcranial Magnetic Stimulation Treatment Outcome: Three Potential Biological Explanations. Front Psychiatry 2022; 13:869070. [PMID: 35573331 PMCID: PMC9098922 DOI: 10.3389/fpsyt.2022.869070] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 04/05/2022] [Indexed: 01/29/2023] Open
Abstract
Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive brain stimulation technique which is now being used in psychiatry clinics across the world as a therapeutic tool for a variety of neural-circuit based disorders (e.g., major depression, obsessive compulsive disorder, substance use disorders, post-traumatic stress disorder, headache, pain). The higher volume of use and publication of multiple large-scale clinical trials has provided researchers with a unique opportunity to retrospectively evaluate factors influencing TMS treatment responses in large samples of patients. While many studies have focused on TMS protocol parameters as moderators of treatment efficacy, sex/gender is another critical, often overlooked factor influencing TMS treatment outcome. Women, especially during periods of high estradiol, appear to be particularly sensitive to the therapeutic effects of rTMS. This manuscript makes a case for three potential biological explanations for these findings. Drawing on literature from cranio-facial anatomy, neuroimaging, and neuroendocrine fields, we posit that observed increases in response rates of women in clinical rTMS trials may be related to: (1) Closer proximity of the brain to the scalp at the prefrontal cortex, leading to larger TMS induced electric fields especially at the medial prefrontal cortex, (2) Greater gray matter density and gyrification in the prefrontal cortex, and (3) High levels of estradiol which facilitate cortical excitability. These biological explanations are empirical ideas which have been evaluated in laboratory studies and lend themselves to prospective evaluation in multisite clinical rTMS trials. The existing literature on this topic and these three potential biological explanations all indicate that the TMS field should routinely evaluate sex/gender (and associated biological metrics like scalp-to-cortex distance, gray matter density, estradiol/progesterone levels) as a factor that may influence treatment outcome.
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Affiliation(s)
- Colleen A Hanlon
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Daniel M McCalley
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States
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15
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Warwick RM, Shumer DE. Gender-affirming multidisciplinary care for transgender and non-binary children and adolescents. CHILDRENS HEALTH CARE 2021. [DOI: 10.1080/02739615.2021.2004146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
| | - Daniel E. Shumer
- Department of Pediatrics, Division of Pediatric Endocrinology, Michigan Medicine, Ann Arbor, MI, USA
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16
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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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17
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Frigerio A, Ballerini L, Valdés Hernández M. Structural, Functional, and Metabolic Brain Differences as a Function of Gender Identity or Sexual Orientation: A Systematic Review of the Human Neuroimaging Literature. ARCHIVES OF SEXUAL BEHAVIOR 2021; 50:3329-3352. [PMID: 33956296 PMCID: PMC8604863 DOI: 10.1007/s10508-021-02005-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 04/06/2021] [Accepted: 04/08/2021] [Indexed: 05/05/2023]
Abstract
This review systematically explored structural, functional, and metabolic features of the cisgender brain compared with the transgender brain before hormonal treatment and the heterosexual brain compared to the homosexual brain from the analysis of the neuroimaging literature up to 2018, and identified and discussed subsequent studies published up to March 2021. Our main aim was to help identifying neuroradiological brain features that have been related to human sexuality to contribute to the understanding of the biological elements involved in gender identity and sexual orientation. We analyzed 39 studies on gender identity and 24 on sexual orientation. Our results suggest that some neuroanatomical, neurophysiological, and neurometabolic features in transgender individuals resemble those of their experienced gender despite the majority resembling those from their natal sex. In homosexual individuals the majority resemble those of their same-sex heterosexual population rather than their opposite-sex heterosexual population. However, it is always difficult to interpret findings with noninvasive neuroimaging. Given the gross nature of these measures, it is possible that more differences too subtle to measure with available tools yet contributing to gender identity and sexual orientation could be found. Conflicting results contributed to the difficulty of identifying specific brain features which consistently differ between cisgender and transgender or between heterosexual and homosexual groups. The small number of studies, the small-to-moderate sample size of each study, and the heterogeneity of the investigations made it impossible to meta-analyze all the data extracted. Further studies are necessary to increase the understanding of the neurological substrates of human sexuality.
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Affiliation(s)
- Alberto Frigerio
- Division of Health Sciences, University of Edinburgh, Edinburgh, EH16 4SB, UK
| | - Lucia Ballerini
- Division of Health Sciences, University of Edinburgh, Edinburgh, EH16 4SB, UK
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18
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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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19
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Rosenthal SM. Challenges in the care of transgender and gender-diverse youth: an endocrinologist's view. Nat Rev Endocrinol 2021; 17:581-591. [PMID: 34376826 DOI: 10.1038/s41574-021-00535-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/28/2021] [Indexed: 02/07/2023]
Abstract
An increasing number of transgender and gender-diverse (TGD) youth (early pubertal through to late adolescent, typically 9-10 through to 18 years of age) are seeking medical services to bring their physical sex characteristics into alignment with their gender identity - their inner sense of self as male or female or somewhere on the gender spectrum. Compelling research has demonstrated the clear mental health - even life-saving - benefits of gender-affirming care, but current clinical practice guidelines and standards of care are based on only several short-term and a few medium-term outcomes studies complemented by expert opinion. Nevertheless, although the relative paucity of outcomes data raises concerns, the stance of not intervening until more is known is not a neutral option, and large observational studies evaluating current models of care are necessary and are now underway. This Review highlights key advances in our understanding of transgender and gender-diverse youth, the challenges of providing gender-affirming care, gaps in knowledge and priorities for research.
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Affiliation(s)
- Stephen M Rosenthal
- Department of Pediatrics, Division of Pediatric Endocrinology, Benioff Children's Hospital, University of California San Francisco, San Francisco, CA, USA.
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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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Baldinger-Melich P, Urquijo Castro MF, Seiger R, Ruef A, Dwyer DB, Kranz GS, Klöbl M, Kambeitz J, Kaufmann U, Windischberger C, Kasper S, Falkai P, Lanzenberger R, Koutsouleris N. Sex Matters: A Multivariate Pattern Analysis of Sex- and Gender-Related Neuroanatomical Differences in Cis- and Transgender Individuals Using Structural Magnetic Resonance Imaging. Cereb Cortex 2021; 30:1345-1356. [PMID: 31368487 PMCID: PMC7132951 DOI: 10.1093/cercor/bhz170] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 06/28/2019] [Accepted: 06/28/2019] [Indexed: 12/22/2022] Open
Abstract
Univariate analyses of structural neuroimaging data have produced heterogeneous results regarding anatomical sex- and gender-related differences. The current study aimed at delineating and cross-validating brain volumetric surrogates of sex and gender by comparing the structural magnetic resonance imaging data of cis- and transgender subjects using multivariate pattern analysis. Gray matter (GM) tissue maps of 29 transgender men, 23 transgender women, 35 cisgender women, and 34 cisgender men were created using voxel-based morphometry and analyzed using support vector classification. Generalizability of the models was estimated using repeated nested cross-validation. For external validation, significant models were applied to hormone-treated transgender subjects (n = 32) and individuals diagnosed with depression (n = 27). Sex was identified with a balanced accuracy (BAC) of 82.6% (false discovery rate [pFDR] < 0.001) in cisgender, but only with 67.5% (pFDR = 0.04) in transgender participants indicating differences in the neuroanatomical patterns associated with sex in transgender despite the major effect of sex on GM volume irrespective of the self-identification as a woman or man. Gender identity and gender incongruence could not be reliably identified (all pFDR > 0.05). The neuroanatomical signature of sex in cisgender did not interact with depressive features (BAC = 74.7%) but was affected by hormone therapy when applied in transgender women (P < 0.001).
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Affiliation(s)
- Pia Baldinger-Melich
- Department of Psychiatry and Psychotherapy, Clinical Division of General Psychiatry, Medical University of Vienna, Vienna, Austria.,Neuroimaging Labs (NIL) PET, MRI, EEG, TMS and Chemical Lab, Department of Psychiatry and Psychotherapy, Clinical Division of General Psychiatry, Medical University of Vienna, Vienna, Austria
| | - Maria F Urquijo Castro
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Bavaria, Germany.,Section for Neurodiagnostic Applications, Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Bavaria, Germany
| | - René Seiger
- Department of Psychiatry and Psychotherapy, Clinical Division of General Psychiatry, Medical University of Vienna, Vienna, Austria.,Neuroimaging Labs (NIL) PET, MRI, EEG, TMS and Chemical Lab, Department of Psychiatry and Psychotherapy, Clinical Division of General Psychiatry, Medical University of Vienna, Vienna, Austria
| | - Anne Ruef
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Bavaria, Germany.,Section for Neurodiagnostic Applications, Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Bavaria, Germany
| | - Dominic B Dwyer
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Bavaria, Germany.,Section for Neurodiagnostic Applications, Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Bavaria, Germany
| | - Georg S Kranz
- Department of Psychiatry and Psychotherapy, Clinical Division of General Psychiatry, Medical University of Vienna, Vienna, Austria.,Neuroimaging Labs (NIL) PET, MRI, EEG, TMS and Chemical Lab, Department of Psychiatry and Psychotherapy, Clinical Division of General Psychiatry, Medical University of Vienna, Vienna, Austria.,Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Manfred Klöbl
- Department of Psychiatry and Psychotherapy, Clinical Division of General Psychiatry, Medical University of Vienna, Vienna, Austria
| | - Joseph Kambeitz
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Bavaria, Germany.,Section for Neurodiagnostic Applications, Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Bavaria, Germany
| | - Ulrike Kaufmann
- Department of Obstetrics and Gynecology, Medical University of Vienna, Vienna, Austria
| | - Christian Windischberger
- MR Centre of Excellence, Centre for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Siegfried Kasper
- Department of Psychiatry and Psychotherapy, Clinical Division of General Psychiatry, Medical University of Vienna, Vienna, Austria
| | - Peter Falkai
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Bavaria, Germany
| | - Rupert Lanzenberger
- Department of Psychiatry and Psychotherapy, Clinical Division of General Psychiatry, Medical University of Vienna, Vienna, Austria.,Neuroimaging Labs (NIL) PET, MRI, EEG, TMS and Chemical Lab, Department of Psychiatry and Psychotherapy, Clinical Division of General Psychiatry, Medical University of Vienna, Vienna, Austria
| | - Nikolaos Koutsouleris
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Bavaria, Germany.,Section for Neurodiagnostic Applications, Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Bavaria, Germany
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22
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Abstract
Gender identity development is complex and involves several key processes. Transgender people experience incongruence between their biological and identified gender. This incongruence can cause significant impairment in overall functioning and lead to gender dysphoria (GD). The pathophysiology of GD is complex and is poorly understood. A PubMed search based on predetermined eligibility criteria was conducted to review neuropsychiatric articles focused on neurological, biological and neuroimaging aspects of gender development, transgender identity and GD. The information obtained from the literature was then used to formulize a GD model. Distinct gray matter volume and brain activation and connectivity differences were found in individuals with GD compared to controls, suggesting a neurobiological basis of GD; which leads to the concept of brain gender. Individuals with GD encounter a recurrent conflict between their brain gender and the societal feedback; which causes recurrent and ongoing cognitive dissonance, finally leading to GD and functional connectivity and activation changes in the transgender brain. GD has neurobiological basis, but it is closely associated with the individuals' interaction with the external world, their self-perception and the feedback received in return. We propose a novel model where the development of GD includes cognitive dissonance, involving anterior cingulate cortex and ventral striatum as the key brain structures. This model can be used to generate testable hypotheses using behavioral and neuroimaging techniques to understand the neuropsychobiology of GD.
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Affiliation(s)
- Murat Altinay
- Center for Behavioral Health, Cleveland Clinic, 9500 Euclid Avenue/P57, Cleveland, OH, 44195, USA.
| | - Amit Anand
- Center for Behavioral Health, Cleveland Clinic, 9500 Euclid Avenue/P57, Cleveland, OH, 44195, USA
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23
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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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24
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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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25
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Treichler EBH, Palmer BW, Wu TC, Thomas ML, Tu XM, Daly R, Lee EE, Jeste DV. Women and Men Differ in Relative Strengths in Wisdom Profiles: A Study of 659 Adults Across the Lifespan. Front Psychol 2021; 12:769294. [PMID: 35185678 PMCID: PMC8850272 DOI: 10.3389/fpsyg.2021.769294] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 12/16/2021] [Indexed: 01/14/2023] Open
Abstract
Wisdom is a multi-component trait that is important for mental health and well-being. In this study, we sought to understand gender differences in relative strengths in wisdom. A total of 659 individuals aged 27-103 years completed surveys including the 3-Dimensional Wisdom Scale (3D-WS) and the San Diego Wisdom Scale (SD-WISE). Analyses assessed gender differences in wisdom and gender's moderating effect on the relationship between wisdom and associated constructs including depression, loneliness, well-being, optimism, and resilience. Women scored higher on average on the 3D-WS but not on the SD-WISE. Women scored higher on compassion-related domains and on SD-WISE Self-Reflection. Men scored higher on cognitive-related domains and on SD-WISE Emotion Regulation. There was no impact of gender on the relationships between wisdom and associated constructs. Women and men have different relative strengths in wisdom, likely driven by sociocultural and biological factors. Tailoring wisdom interventions to individuals based on their profiles is an important next step.
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Affiliation(s)
- Emily B H Treichler
- VA Desert Pacific Mental Illness Research, Education, and Clinical Center (MIRECC), San Diego, CA, United States.,Department of Psychiatry, University of California, San Diego, San Diego, CA, United States.,Sam and Rose Stein Institute for Research on Aging, University of California, San Diego, San Diego, CA, United States
| | - Barton W Palmer
- VA Desert Pacific Mental Illness Research, Education, and Clinical Center (MIRECC), San Diego, CA, United States.,Department of Psychiatry, University of California, San Diego, San Diego, CA, United States.,VA San Diego Healthcare System, San Diego, CA, United States
| | - Tsung-Chin Wu
- Sam and Rose Stein Institute for Research on Aging, University of California, San Diego, San Diego, CA, United States.,Department of Family Medicine and Public Health, University of California, San Diego, San Diego, CA, United States
| | - Michael L Thomas
- Department of Psychology, Colorado State University, Fort Collins, CO, United States
| | - Xin M Tu
- Sam and Rose Stein Institute for Research on Aging, University of California, San Diego, San Diego, CA, United States.,Department of Family Medicine and Public Health, University of California, San Diego, San Diego, CA, United States
| | - Rebecca Daly
- VA Desert Pacific Mental Illness Research, Education, and Clinical Center (MIRECC), San Diego, CA, United States.,Department of Psychiatry, University of California, San Diego, San Diego, CA, United States
| | - Ellen E Lee
- VA Desert Pacific Mental Illness Research, Education, and Clinical Center (MIRECC), San Diego, CA, United States.,Department of Psychiatry, University of California, San Diego, San Diego, CA, United States.,VA San Diego Healthcare System, San Diego, CA, United States
| | - Dilip V Jeste
- VA Desert Pacific Mental Illness Research, Education, and Clinical Center (MIRECC), San Diego, CA, United States.,Department of Psychiatry, University of California, San Diego, San Diego, CA, United States.,Department of Neurosciences, University of California, San Diego, San Diego, CA, United States
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Karalexi MA, Georgakis MK, Dimitriou NG, Vichos T, Katsimpris A, Petridou ET, Papadopoulos FC. Gender-affirming hormone treatment and cognitive function in transgender young adults: a systematic review and meta-analysis. Psychoneuroendocrinology 2020; 119:104721. [PMID: 32512250 DOI: 10.1016/j.psyneuen.2020.104721] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 05/18/2020] [Accepted: 05/19/2020] [Indexed: 01/04/2023]
Abstract
BACKGROUND Previous studies have examined whether steroid hormone treatment in transgender individuals may affect cognitive function; yet, their limited power does not allow firm conclusions to be drawn. We leveraged data from to-date literature aiming to explore the effect of gender-affirming hormone administration on cognitive function in transgender individuals. METHODS A search strategy of MEDLINE was developed (through June 1, 2019) using the key terms transgender, hormone therapy and cognitive function. Eligible were (i) cohort studies examining the longitudinal effect of hormone therapy on cognition, and (ii) cross-sectional studies comparing the cognitive function between treated and non-treated individuals. Standardized mean differences (Hedges' g) were pooled using random-effects models. Study quality was evaluated using the Newcastle-Ottawa Scale. OUTCOMES Ten studies (seven cohort and three cross-sectional) were eligible representing 234 birth-assigned males (aM) and 150 birth-assigned females (aF). The synthesis of cohort studies (n = 5) for visuospatial ability following hormone treatment showed a statistically significant enhancement among aF (g = 0.55, 95% confidence intervals [CI]: 0.29, 0.82) and an improvement with a trend towards statistical significance among aM (g = 0.28, 95%CI: -0.01, 0.58). By contrast, no adverse effects of hormone administration were shown. No heterogeneity was evident in most meta-analyses. INTERPRETATION Current evidence does not support an adverse impact of hormone therapy on cognitive function, whereas a statistically significant enhancing effect on visuospatial ability was shown in aF. New longitudinal studies with longer follow-up should explore the long-term effects of hormone therapy, especially the effects on younger individuals, where there is greater scarcity of data.
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Affiliation(s)
- Maria A Karalexi
- Department of Hygiene, Epidemiology and Medical Statistics, Medical School, National and Kapodistrian University of Athens, Athens, Greece; Department of Neuroscience, Psychiatry, Uppsala University, Uppsala University Hospital, Uppsala, Sweden
| | - Marios K Georgakis
- Department of Hygiene, Epidemiology and Medical Statistics, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Nikolaos G Dimitriou
- Department of Hygiene, Epidemiology and Medical Statistics, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Theodoros Vichos
- Department of Hygiene, Epidemiology and Medical Statistics, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Andreas Katsimpris
- Department of Hygiene, Epidemiology and Medical Statistics, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Eleni Th Petridou
- Department of Hygiene, Epidemiology and Medical Statistics, Medical School, National and Kapodistrian University of Athens, Athens, Greece; Unit of Clinical Epidemiology, Karolinska Institute, Stockholm, Sweden
| | - Fotios C Papadopoulos
- Department of Neuroscience, Psychiatry, Uppsala University, Uppsala University Hospital, Uppsala, Sweden.
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Frohard-Dourlent H, Saewyc E, Peter T, MacAulay M. Conceptualizing Gender: Lessons from the Canadian Trans Youth Health Survey. SIGNS 2020. [DOI: 10.1086/709302] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Byne W, Karasic DH, Coleman E, Eyler AE, Kidd JD, Meyer-Bahlburg HFL, Pleak RR, Pula J. Gender Dysphoria in Adults: An Overview and Primer for Psychiatrists. FOCUS: JOURNAL OF LIFE LONG LEARNING IN PSYCHIATRY 2020; 18:336-350. [PMID: 33343244 DOI: 10.1176/appi.focus.18304] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
(Copyright © William Byne et al. 2018; Published by Mary Ann Liebert, Inc. This Open Access article is distributed under the terms of the Creative Commons License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.).
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Westwater JJ, Riley E, Peterson GM. Using circular questions to explore individual family member experiences of youth gender dysphoria in Australia. INTERNATIONAL JOURNAL OF TRANSGENDER HEALTH 2020; 21:321-336. [PMID: 34993512 PMCID: PMC8726649 DOI: 10.1080/26895269.2020.1777616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Background: The number of young people reporting gender dysphoria is increasing worldwide, with gender dysphoria known to affect everyone in the family in unique ways. Previous research has highlighted the importance of family support and understanding; however, much less is known about individual and collective family member experiences, particularly for siblings under the age of 18 years. Aims: This study sought to identify, describe and interpret individual family member experiences of youth gender dysphoria using semi-structured interviews, incorporating circular questioning, within a whole of family, clinical and wider social context. Methods: Thirty-five individual family members living in Australia (nine young people aged 12-17 years experiencing gender dysphoria, 10 mothers, eight fathers, and eight siblings aged 11-17 years) were interviewed, exploring positive and negative experiences of youth gender dysphoria, within and outside of the family. Family relationships, support and healthcare experiences were also explored. Results: All participants reported a mixture of positive and negative experiences of youth gender dysphoria. Levels of acceptance tended to change with the duration of transition, with most family members adapting with time. Siblings reported mixed experiences within the same family, with some struggling to adapt. Most family members felt that including the whole family in the healthcare of the young person was important, although dependent on individual circumstances and family context. Specialist gender care experiences were unanimously positive, although services were considered difficult to access. Discussion: Family members reported shared and individual positive and negative experiences of youth gender dysphoria across social contexts. Accepting and facilitating gender transition for young people appeared to improve individual and family functioning. Most participants valued a whole of family approach within specialist healthcare. The use of circular questioning in the study helped dispel assumptions and facilitated curiosity for others' experiences in the family.
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Affiliation(s)
| | - Elizabeth Riley
- School of Medicine, University of Tasmania, Hobart, Australia
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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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Ackermann C, Andronikou S, Saleh MG, Kidd M, Cotton MF, Meintjes EM, Laughton B. Diffusion tensor imaging point to ongoing functional impairment in HIV-infected children at age 5, undetectable using standard neurodevelopmental assessments. AIDS Res Ther 2020; 17:20. [PMID: 32430069 PMCID: PMC7236356 DOI: 10.1186/s12981-020-00278-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 05/08/2020] [Indexed: 11/30/2022] Open
Abstract
Background Perinatal HIV infection negatively impacts cognitive functioning of children, main domains affected are working memory, processing speed and executive function. Early ART, even when interrupted, improves neurodevelopmental outcomes. Diffusion tension imaging (DTI) is a sensitive tool assessing white matter damage. We hypothesised that white matter measures in regions showing HIV-related alterations will be associated with lower neurodevelopmental scores in specific domains related to the functionality of the affected tracts. Methods DTI was performed on children in a neurodevelopmental sub study from the Children with HIV Early Antiretroviral (CHER) trial. Voxel-based group comparisons to determine regions where fractional anisotropy and mean diffusion differed between HIV+ and uninfected children were done. Locations of clusters showing group differences were identified using the Harvard–Oxford cortical and subcortical and John Hopkins University WM tractography atlases provided in FSL. This is a second review of DTI data in this cohort, which was reported in a previous study. Neurodevelopmental assessments including GMDS and Beery-Buktenica tests were performed and correlated with DTI parameters in abnormal white matter. Results 38 HIV+ children (14 male, mean age 64.7 months) and 11 controls (4 male, mean age 67.7 months) were imaged. Two clusters with lower fractional anisotropy and 7 clusters with increased mean diffusion were identified in the HIV+ group. The only neurodevelopmental domain with a trend of difference between the HIV+ children and controls (p = 0.08), was Personal Social Quotient which correlated to improved myelination of the forceps minor in the control group. As a combined group there was a negative correlation between visual perception and radial diffusion in the right superior longitudinal fasciculus and left inferior longitudinal fasciculus, which may be related to the fact that these tracts, forming part of the visual perception pathway, are at a crucial state of development at age 5. Conclusion Even directed neurodevelopmental tests will underestimate the degree of microstructural white matter damage detected by DTI. The visual perception deficit detected in the entire study population should be further examined in a larger study.
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Uribe C, Junque C, Gómez-Gil E, Abos A, Mueller SC, Guillamon A. Brain network interactions in transgender individuals with gender incongruence. Neuroimage 2020; 211:116613. [DOI: 10.1016/j.neuroimage.2020.116613] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 02/04/2020] [Indexed: 12/31/2022] Open
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Ristori J, Cocchetti C, Romani A, Mazzoli F, Vignozzi L, Maggi M, Fisher AD. Brain Sex Differences Related to Gender Identity Development: Genes or Hormones? Int J Mol Sci 2020; 21:ijms21062123. [PMID: 32204531 PMCID: PMC7139786 DOI: 10.3390/ijms21062123] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 02/21/2020] [Accepted: 02/28/2020] [Indexed: 12/19/2022] Open
Abstract
The complex process of sexual differentiation is known to be influenced by biological and environmental determinants. The present review has the aim of summarizing the most relevant studies on the biological basis of sexual development, and in particular, it focuses on the impact of sex hormones and genetic background on the development of sexual differentiation and gender identity. The authors conducted a search of published studies on Medline (from January 1948 to December 2019). The evidence suggests that the sexual dimorphic brain could be the anatomical substrate of psychosexual development, on which gonadal hormones may have a shaping role during prenatal and pubertal periods. Additionally, according to several heritability studies, genetic components may have a role, but a promising candidate gene has not been identified. Even though growing evidence underlines the primary role of biological factors on psychosexual development, further studies are necessary to better explain their complex interactions.
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Affiliation(s)
- Jiska Ristori
- Andrology, Women’s Endocrinology and Gender Incongruence, Careggi University Hospital, Viale Pieraccini 6, 50139 Florence, Italy; (J.R.); (C.C.); (A.R.); (F.M.); (L.V.)
| | - Carlotta Cocchetti
- Andrology, Women’s Endocrinology and Gender Incongruence, Careggi University Hospital, Viale Pieraccini 6, 50139 Florence, Italy; (J.R.); (C.C.); (A.R.); (F.M.); (L.V.)
| | - Alessia Romani
- Andrology, Women’s Endocrinology and Gender Incongruence, Careggi University Hospital, Viale Pieraccini 6, 50139 Florence, Italy; (J.R.); (C.C.); (A.R.); (F.M.); (L.V.)
| | - Francesca Mazzoli
- Andrology, Women’s Endocrinology and Gender Incongruence, Careggi University Hospital, Viale Pieraccini 6, 50139 Florence, Italy; (J.R.); (C.C.); (A.R.); (F.M.); (L.V.)
| | - Linda Vignozzi
- Andrology, Women’s Endocrinology and Gender Incongruence, Careggi University Hospital, Viale Pieraccini 6, 50139 Florence, Italy; (J.R.); (C.C.); (A.R.); (F.M.); (L.V.)
| | - Mario Maggi
- Endocrinology, Careggi University Hospital, Viale Pieraccini 6, 50139 Florence, Italy;
| | - Alessandra Daphne Fisher
- Andrology, Women’s Endocrinology and Gender Incongruence, Careggi University Hospital, Viale Pieraccini 6, 50139 Florence, Italy; (J.R.); (C.C.); (A.R.); (F.M.); (L.V.)
- Correspondence:
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Bowers MM, Whitley CT. What Drives Support for Transgender Rights? Assessing the Effects of Biological Attribution on U.S. Public Opinion of Transgender Rights. SEX ROLES 2020. [DOI: 10.1007/s11199-019-01118-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Weiselberg EC, Shadianloo S, Fisher M. Overview of care for transgender children and youth. Curr Probl Pediatr Adolesc Health Care 2019; 49:100682. [PMID: 31706835 DOI: 10.1016/j.cppeds.2019.100682] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Over the past decade, more and more children and adolescents are identifying as transgender and gender diverse (TGD). Often, they and their parents first turn to their primary care pediatrician for guidance and support. Therefore, in 2018, the American Academy of Pediatrics (AAP) released a policy statement focusing on the health care of TGD youth.4 The AAP acknowledges that many pediatricians have a lack of training in this area and therefore need to increase their knowledge base and expertise in order to provide culturally competent care. While most sexual and gender minority individuals are healthy and well adjusted, some TGD youth are at an increased risk of mental health concerns, including anxiety, depression, substance abuse, eating disorders and suicidality. This is theorized to be due to the experienced or internalized marginalization, stigmatization, victimization, harassment or rejection and not inherent in having gender dysphoria or being transgender. The pediatrician therefore needs to be knowledgeable of, and skilled to screen for, the health disparities that may exist, as well as to be able to support the individual who may disclose their gender identity status during treatment. Parents and guardians may also turn to the pediatrician for guidance when faced with their child who presents with gender non-conforming behaviors or gender dysphoria. Therefore the pediatrician needs to be able to guide the parents as well, as their acceptance and support of their child's journey to gender identity is probably the most important protective factor against health disparities encountered. To deliver optimum care for TGD children and youth, the pediatrician needs to establish an office setting that is inclusive, gender-neutral and TGD friendly. By becoming familiar with the diversity of gender expression and identities, use of gender-appropriate terminology, health disparities often encountered and the importance of providing a safe and welcoming environment, issues that are all covered in this article, the primary care pediatrician will be in position to provide comprehensive health care to this often marginalized population.
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Affiliation(s)
- Eric C Weiselberg
- Division of Adolescent Medicine, Department of Pediatrics, Cohen Children's Medical Center, Northwell Health System, 410 Lakeville Road, Suite 108, New Hyde Park, NY, United States; Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, United States.
| | - Shervin Shadianloo
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, United States; Division of Child and Adolescent Psychiatry, Department of Psychiatry, Zucker Hillside Hospital, Northwell Health, New Hyde Park, NY, United States
| | - Martin Fisher
- Division of Adolescent Medicine, Department of Pediatrics, Cohen Children's Medical Center, Northwell Health System, 410 Lakeville Road, Suite 108, New Hyde Park, NY, United States; Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, United States
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Iwamoto SJ, Defreyne J, Rothman MS, Van Schuylenbergh J, Van de Bruaene L, Motmans J, T’Sjoen G. Health considerations for transgender women and remaining unknowns: a narrative review. Ther Adv Endocrinol Metab 2019; 10:2042018819871166. [PMID: 31516689 PMCID: PMC6719479 DOI: 10.1177/2042018819871166] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 07/31/2019] [Indexed: 12/17/2022] Open
Abstract
Transgender (trans) women (TW) were assigned male at birth but have a female gender identity or gender expression. The literature on management and health outcomes of TW has grown recently with more publication of research. This has coincided with increasing awareness of gender diversity as communities around the world identify and address health disparities among trans people. In this narrative review, we aim to comprehensively summarize health considerations for TW and identify TW-related research areas that will provide answers to remaining unknowns surrounding TW's health. We cover up-to-date information on: (1) feminizing gender-affirming hormone therapy (GAHT); (2) benefits associated with GAHT, particularly quality of life, mental health, breast development and bone health; (3) potential risks associated with GAHT, including cardiovascular disease and infertility; and (4) other health considerations like HIV/AIDS, breast cancer, other tumours, voice therapy, dermatology, the brain and cognition, and aging. Although equally deserving of mention, feminizing gender-affirming surgery, paediatric and adolescent populations, and gender nonbinary individuals are beyond the scope of this review. While much of the data we discuss come from Europe, the creation of a United States transgender cohort has already contributed important retrospective data that are also summarized here. Much remains to be determined regarding health considerations for TW. Patients and providers will benefit from larger and longer prospective studies involving TW, particularly regarding the effects of aging, race and ethnicity, type of hormonal treatment (e.g. different oestrogens, anti-androgens) and routes of administration (e.g. oral, parenteral, transdermal) on all the topics we address.
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Affiliation(s)
- Sean J. Iwamoto
- University of Colorado School of Medicine, Division of Endocrinology, Metabolism and Diabetes, 12801 East 17th Avenue, Mail Stop: 8106, Aurora, CO 80045, USA
- UCHealth Integrated Transgender Program, Anschutz Medical Campus, Aurora, CO, USA
- Division of Endocrinology, Rocky Mountain Regional VA Medical Center, Aurora, CO, USA
| | - Justine Defreyne
- Department of Endocrinology, Ghent University Hospital, Ghent, Belgium
| | - Micol S. Rothman
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, CO, USA
- UCHealth Integrated Transgender Program, Anschutz Medical Campus, Aurora, CO, USA
| | | | | | - Joz Motmans
- Center for Sexology and Gender, Ghent University Hospital, Ghent, Belgium
- Center for Research on Culture and Gender, Ghent University, Ghent, Belgium
| | - Guy T’Sjoen
- Department of Endocrinology, Ghent University Hospital, Ghent, Belgium
- Center for Sexology and Gender, Ghent University Hospital, Ghent, Belgium
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McKeague M, Terry SF. Let's Talk About Sex: Understanding Gender Beyond Genetics. Genet Test Mol Biomarkers 2019; 23:599-600. [PMID: 31408365 DOI: 10.1089/gtmb.2019.29048.sjt] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Diekfuss JA, Grooms DR, Nissen KS, Schneider DK, Foss KDB, Thomas S, Bonnette S, Dudley JA, Yuan W, Reddington DL, Ellis JD, Leach J, Gordon M, Lindsey C, Rushford K, Shafer C, Myer GD. Alterations in knee sensorimotor brain functional connectivity contributes to ACL injury in male high-school football players: a prospective neuroimaging analysis. Braz J Phys Ther 2019; 24:415-423. [PMID: 31377125 DOI: 10.1016/j.bjpt.2019.07.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 07/02/2019] [Accepted: 07/03/2019] [Indexed: 01/13/2023] Open
Abstract
OBJECTIVE This study's purpose was to utilize a prospective dataset to examine differences in functional brain connectivity in male high school athletes who suffered an anterior cruciate ligament (ACL) injury relative to their non-injured peers. METHODS Sixty-two male high school football players were evaluated using functional magnetic resonance imaging prior to their competitive season to evaluate resting-state functional brain connectivity. Three athletes later experienced an ACL injury and were matched to 12 teammates who did not go on to sustain an ACL injury (controls) based on school, age, height, weight, and year in school. Twenty-five knee-motor regions of interest (ROIs) were created to identify differences in connectivity between the two groups. Between-subject F and t tests were used to identify significant ROI differences using a false discovery rate correction for multiple comparisons. RESULTS There was significantly less connectivity between the left secondary somatosensory cortex and the left supplementary motor area (p = 0.025), right pre-motor cortex (p = 0.026), right supplementary motor area (p = 0.026), left primary somatosensory cortex (superior division; p = 0.026), left primary somatosensory cortex (inferior division; p = 0.026), and left primary motor cortex (p = 0.048) for the ACL-injured compared to the control subjects. No other ROI-to-ROI comparisons were significantly different between the groups (all p > 0.05). CONCLUSION Our preliminary data indicate a potential sensorimotor disruption for male football players who go on to experience an ACL injury. Future studies with larger sample sizes and complementary measures of neuromuscular control are needed to support these findings.
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Affiliation(s)
- Jed A Diekfuss
- The SPORT Center, Division of Sports Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
| | - Dustin R Grooms
- Ohio Musculoskeletal & Neurological Institute and Division of Athletic Training, School of Applied Health Sciences and Wellness, College of Health Sciences and Professions, Ohio University, Athens, OH, USA
| | - Katharine S Nissen
- The SPORT Center, Division of Sports Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Daniel K Schneider
- The SPORT Center, Division of Sports Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA; Riverside Methodist Hospital, Columbus, OH, USA
| | - Kim D Barber Foss
- The SPORT Center, Division of Sports Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Staci Thomas
- The SPORT Center, Division of Sports Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Scott Bonnette
- The SPORT Center, Division of Sports Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Jonathan A Dudley
- Pediatric Neuroimaging Research Consortium, Cincinnati Children's Hospital Medical Center, Ohio, USA
| | - Weihong Yuan
- Pediatric Neuroimaging Research Consortium, Cincinnati Children's Hospital Medical Center, Ohio, USA; University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Danielle L Reddington
- The SPORT Center, Division of Sports Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Jonathan D Ellis
- The SPORT Center, Division of Sports Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA; University of Cincinnati Medical Center, Department of Orthopaedic Surgery, Cincinnati, OH, USA
| | - James Leach
- University of Cincinnati College of Medicine, Cincinnati, OH, USA; Division of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | | | | | | | | | - Gregory D Myer
- The SPORT Center, Division of Sports Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA; Departments of Pediatrics and Orthopaedic Surgery, University of Cincinnati, Cincinnati, OH, USA; The Micheli Center for Sports Injury Prevention, Waltham, MA, USA
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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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Manzouri A, Savic I. Possible Neurobiological Underpinnings of Homosexuality and Gender Dysphoria. Cereb Cortex 2019; 29:2084-2101. [PMID: 30084980 PMCID: PMC6677918 DOI: 10.1093/cercor/bhy090] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 03/13/2018] [Accepted: 04/03/2018] [Indexed: 01/13/2023] Open
Abstract
Although frequently discussed in terms of sex dimorphism, the neurobiology of sexual orientation and identity is unknown. We report multimodal magnetic resonance imaging data, including cortical thickness (Cth), subcortical volumes, and resting state functional magnetic resonance imaging, from 27 transgender women (TrW), 40 transgender men (TrM), and 80 heterosexual (40 men) and 60 homosexual cisgender controls (30 men). These data show that whereas homosexuality is linked to cerebral sex dimorphism, gender dysphoria primarily involves cerebral networks mediating self-body perception. Among the homosexual cisgender controls, weaker sex dimorphism was found in white matter connections and a partly reversed sex dimorphism in Cth. Similar patterns were detected in transgender persons compared with heterosexual cisgender controls, but the significant clusters disappeared when adding homosexual controls, and correcting for sexual orientation. Instead, both TrW and TrM displayed singular features, showing greater Cth as well as weaker structural and functional connections in the anterior cingulate-precuneus and right occipito-parietal cortex, regions known to process own body perception in the context of self.
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Affiliation(s)
- A Manzouri
- Department of Women’s and Children’s Health, Karolinska Institute and University Hospital, Stockholm, Sweden
| | - I 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, CA, USA
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41
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Kim GW, Kim YH, Park K, Jeong GW. A comparative study of white matter volume between postoperative female-to-male transsexuals and healthy female. Int J Impot Res 2019; 31:432-438. [PMID: 30679768 DOI: 10.1038/s41443-019-0111-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 08/14/2018] [Accepted: 12/03/2018] [Indexed: 12/21/2022]
Abstract
Cross-sex hormones in female-to-male (FtM) transsexuals play a crucial role in brain plasticity. Morphological study associated with white matter (WM) volume in postoperative FtM transsexuals receiving cross-sex hormones has not been published yet. This study was performed to discriminate the regional WM volume differences between postoperative FtM transsexuals and female controls using voxel-based morphometry (VBM) and further to assess the correlations between regional volume variations and cross-sex hormones. WM volume was assessed in 12 postoperative FtM transsexuals receiving cross-sex hormones with 16 age-matched female controls. WM volume was processed using SPM8 software with diffeomorphic anatomical registration via an exponentiated Lie algebra (DARTEL) algorithm. Serum sex hormones, including estriol, free testosterone (free-T), estradiol, follicle-stimulating hormone, and luteinizing hormone were measured. Postoperative FtM transsexuals showed significantly (p < 0.05) larger WM volumes in the inferior parietal lobule, postcentral gyrus, and middle temporal gyrus compared with female controls. However, there were no brain areas with larger WM volume in female controls compared with FtM transsexuals. WM volumes of the inferior parietal lobule and middle temporal gyrus in FtM transsexuals were positively correlated with the levels of free-T. This study revealed WM volume change and its correlation with free-T level in postoperative FtM transsexuals. These findings will improve our understanding of the morphometric changes in FtM transsexuals under cross-sex hormone therapy.
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Affiliation(s)
- Gwang-Won Kim
- Advanced Institute of Aging Science, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Yun-Hyeon Kim
- Department of Radiology, Chonnam National University Hospital, Chonnam National University Medical School, Gwangju, 61469, Republic of Korea
| | - Kwangsung Park
- Advanced Institute of Aging Science, Chonnam National University, Gwangju, 61186, Republic of Korea.,Department of Urology, Chonnam National University Hospital, Chonnam National University Medical School, Gwangju, 61469, Republic of Korea
| | - Gwang-Woo Jeong
- Department of Radiology, Chonnam National University Hospital, Chonnam National University Medical School, Gwangju, 61469, Republic of Korea.
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42
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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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43
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Abstract
BACKGROUND There is growing awareness and exposure in both the medical community and the lay media about the characteristics and complex needs of individuals who believe that their gender identity does not match their birth sex. Despite research and lay publications about teens with gender dysphoria and those who identify as transgender, little guidance is available regarding young (prepubertal) children with questions about their gender identity. Although many terms are used to describe these children, we have chosen to describe them as "gender nonconforming" (GNC). OBJECTIVE Primary care and developmental-behavioral pediatric providers are often the first professionals with whom young gender nonconforming children and their families discuss their concerns about their emerging gender identity. It is important, therefore, that pediatric providers be knowledgeable about the dilemmas, conflicts, and choices that are typical of these children and their families to guide them appropriately. OVERVIEW In this special article, we present observations, informed by clinical experience, an emerging body of research, and a developmental-behavioral pediatric framework, of the complex needs of prepubertal gender nonconforming children and their families and an approach to their care. The article begins by outlining the cognitive and biological bases for gender identity development, as well as the natural history of gender nonconforming preferences and behaviors. It then sets the context for understanding the care of GNC children as an area in which developmentally sophisticated providers can play a crucial role in support of the complex developmental patterns and need for advocacy in multiple settings among these children.
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44
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Roselli CE. Neurobiology of gender identity and sexual orientation. J Neuroendocrinol 2018; 30:e12562. [PMID: 29211317 PMCID: PMC6677266 DOI: 10.1111/jne.12562] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 11/03/2017] [Accepted: 11/28/2017] [Indexed: 12/15/2022]
Abstract
Sexual identity and sexual orientation are independent components of a person's sexual identity. These dimensions are most often in harmony with each other and with an individual's genital sex, although not always. The present review discusses the relationship of sexual identity and sexual orientation to prenatal factors that act to shape the development of the brain and the expression of sexual behaviours in animals and humans. One major influence discussed relates to organisational effects that the early hormone environment exerts on both gender identity and sexual orientation. Evidence that gender identity and sexual orientation are masculinised by prenatal exposure to testosterone and feminised in it absence is drawn from basic research in animals, correlations of biometric indices of androgen exposure and studies of clinical conditions associated with disorders in sexual development. There are, however, important exceptions to this theory that have yet to be resolved. Family and twin studies indicate that genes play a role, although no specific candidate genes have been identified. Evidence that relates to the number of older brothers implicates maternal immune responses as a contributing factor for male sexual orientation. It remains speculative how these influences might relate to each other and interact with postnatal socialisation. Nonetheless, despite the many challenges to research in this area, existing empirical evidence makes it clear that there is a significant biological contribution to the development of an individual's sexual identity and sexual orientation.
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Affiliation(s)
- C E Roselli
- Department of Physiology & Pharmacology, Oregon Health & Science University, Portland, OR, USA
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45
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Mohammadi MR, Khaleghi A. Transsexualism: A Different Viewpoint to Brain Changes. CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE 2018; 16:136-143. [PMID: 29739126 PMCID: PMC5953012 DOI: 10.9758/cpn.2018.16.2.136] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 02/12/2018] [Accepted: 02/13/2018] [Indexed: 01/13/2023]
Abstract
Transsexualism refers to a condition or belief which results in gender dysphoria in individuals and makes them insist that their biological gender is different from their psychological and experienced gender. Although the etiology of gender dysphoria (or transsexualism) is still unknown, different neuroimaging studies show that structural and functional changes of the brain result from this sexual incongruence. The question here is whether these reported changes form part of the etiology of transsexualism or themselves result from transsexualism culture, behaviors and lifestyle. Responding to this question can be more precise by consideration of cultural neuroscience concepts, particularly the culture–behavior–brain (CBB) loop model and the interactions between behavior, culture and brain. In this article, we first review the studies on the brain of transgender people and then we will discuss the validity of this claim based on the CBB loop model. In summary, transgender individuals experience change in lifestyle, context of beliefs and concepts and, as a result, their culture and behaviors. Given the close relationship and interaction between culture, behavior and brain, the individual’s brain adapts itself to the new condition (culture) and concepts and starts to alter its function and structure.
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Affiliation(s)
- Mohammad Reza Mohammadi
- Psychiatry & Psychology Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Ali Khaleghi
- Psychiatry & Psychology Research Center, Tehran University of Medical Sciences, Tehran, Iran
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46
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Fisher AD, Ristori J, Morelli G, Maggi M. The molecular mechanisms of sexual orientation and gender identity. Mol Cell Endocrinol 2018; 467:3-13. [PMID: 28847741 DOI: 10.1016/j.mce.2017.08.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 08/02/2017] [Accepted: 08/15/2017] [Indexed: 12/21/2022]
Abstract
Differences between males and females are widely represented in nature. There are gender differences in phenotypes, personality traits, behaviors and interests, cognitive performance, and proneness to specific diseases. The most marked difference in humans is represented by sexual orientation and core gender identity, the origins of which are still controversial and far from being understood. Debates continue on whether sexual behavior and gender identity are a result of biological (nature) or cultural (nurture) factors, with biology possibly playing a major role. The main goal of this review is to summarize the studies available to date on the biological factors involved in the development of both sexual orientation and gender identity. A systematic search of published evidence was performed using Medline (from January 1948 to June 2017). Review of the relevant literature was based on authors' expertise. Indeed, different studies have documented the possible role and interaction of neuroanatomic, hormonal and genetic factors. The sexual dimorphic brain is considered the anatomical substrate of psychosexual development, on which genes and gonadal hormones may have a shaping effect. In particular, growing evidence shows that prenatal and pubertal sex hormones permanently affect human behavior. In addition, heritability studies have demonstrated a role of genetic components. However, a convincing candidate gene has not been identified. Future studies (e.i. genome wide studies) are needed to better clarify the complex interaction between genes, anatomy and hormonal influences on psychosexual development.
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Affiliation(s)
- Alessandra D Fisher
- Department of Experimental, Clinical and Biomedical Sciences, Careggi University Hospital, Florence, Italy
| | - Jiska Ristori
- Department of Experimental, Clinical and Biomedical Sciences, Careggi University Hospital, Florence, Italy
| | - Girolamo Morelli
- Department of Surgical, Medical, Molecular and of the Critical Area Pathology, University of Pisa, Pisa, Italy
| | - Mario Maggi
- Department of Experimental, Clinical and Biomedical Sciences, Careggi University Hospital, Florence, Italy.
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Byne W, Karasic DH, Coleman E, Eyler AE, Kidd JD, Meyer-Bahlburg HF, Pleak RR, Pula J. Gender Dysphoria in Adults: An Overview and Primer for Psychiatrists. Transgend Health 2018; 3:57-70. [PMID: 29756044 PMCID: PMC5944396 DOI: 10.1089/trgh.2017.0053] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Regardless of their area of specialization, adult psychiatrists are likely to encounter gender-variant patients; however, medical school curricula and psychiatric residency training programs devote little attention to their care. This article aims to assist adult psychiatrists who are not gender specialists in the delivery of respectful, clinically competent, and culturally attuned care to gender-variant patients, including those who identify as transgender or transsexual or meet criteria for the diagnosis of Gender Dysphoria (GD) as defined by The Diagnostic and Statistical Manual of Mental Disorders (5th edition). The article will also be helpful for other mental health professionals. The following areas are addressed: evolution of diagnostic nosology, epidemiology, gender development, and mental health assessment, differential diagnosis, treatment, and referral for gender-affirming somatic treatments of adults with GD.
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Affiliation(s)
- William Byne
- Mental Illness Research Education and Clinical Center, James J Peters VA Medical Center, Bronx, New York
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai and Center for Transgender Medicine and Surgery at Mount Sinai, New York, New York
| | - Dan H. Karasic
- Department of Psychiatry, University of California, San Francisco, San Francisco, California
| | - Eli Coleman
- Program in Human Sexuality, Department of Family Medicine and Community Health, University of Minnesota Medical School, Minneapolis, Minnesota
| | - A. Evan Eyler
- Departments of Psychiatry and Family Medicine, University of Vermont College of Medicine, Burlington, Vermont
| | - Jeremy D. Kidd
- Department of Psychiatry, Division on Substance Use Disorders, College of Physicians and Surgeons of Columbia University, New York, New York
| | - Heino F.L. Meyer-Bahlburg
- Division of Gender, Sexuality, and Health, New York State Psychiatric Institute/Department of Psychiatry, College of Physicians and Surgeons of Columbia University, New York, New York
| | - Richard R. Pleak
- Department of Psychiatry, Division of Child and Adolescent Psychiatry, Hofstra North Shore-LIJ School of Medicine, Albert Einstein College of Medicine, Zucker Hillside Hospital, Ambulatory Care Pavilion, Glen Oaks, New York
| | - Jack Pula
- Department of Psychiatry, Division of Gender, Sexuality and Health, College of Physicians and Surgeons of Columbia University, New York, New York
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48
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Burke SM, Manzouri AH, Dhejne C, Bergström K, Arver S, Feusner JD, Savic-Berglund I. Testosterone Effects on the Brain in Transgender Men. Cereb Cortex 2018; 28:1582-1596. [PMID: 28334217 PMCID: PMC6248653 DOI: 10.1093/cercor/bhx054] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 01/19/2017] [Accepted: 02/16/2017] [Indexed: 12/22/2022] Open
Abstract
Transgender individuals experience incongruence between their gender identity and birth-assigned sex. The resulting gender dysphoria (GD), which some gender-incongruent individuals experience, is theorized to be a consequence of atypical cerebral sexual differentiation, but support for this assertion is inconsistent. We recently found that GD is associated with disconnected networks involved in self-referential thinking and own body perception. Here, we investigate how these networks in trans men (assigned female at birth with male gender identity) are affected by testosterone. In 22 trans men, we obtained T1-weighted, diffusion-weighted, and resting-state functional magnetic resonance imaging scans before and after testosterone treatment, measuring cortical thickness (Cth), subcortical volumes, fractional anisotropy (FA), and functional connectivity. Nineteen cisgender controls (male and female) were also scanned twice. The medial prefrontal cortex (mPFC) was thicker in trans men than controls pretreatment, and remained unchanged posttreatment. Testosterone treatment resulted in increased Cth in the insular cortex, changes in cortico-cortical thickness covariation between mPFC and occipital cortex, increased FA in the fronto-occipital tract connecting these regions, and increased functional connectivity between mPFC and temporo-parietal junction, compared with controls. Concluding, in trans men testosterone treatment resulted in functional and structural changes in self-referential and own body perception areas.
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Affiliation(s)
- Sarah M Burke
- Department of Women's and Children's Health, Karolinska Institutet and
University Hospital, SE-171 76 Stockholm, Sweden
| | | | - Cecilia Dhejne
- ANOVA, Center of Expertise in Andrology, Sexual Medicine, and Transgender
Medicine, Karolinska University Hospital, SE-171 76 Stockholm, Sweden
- Center for Psychiatric Research, Department of Clinical Neuroscience,
Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Karin Bergström
- Department of Women's and Children's Health, Karolinska Institutet and
University Hospital, SE-171 76 Stockholm, Sweden
| | - Stefan Arver
- ANOVA, Center of Expertise in Andrology, Sexual Medicine, and Transgender
Medicine, Karolinska University Hospital, SE-171 76 Stockholm, Sweden
- Department of Medicine/Huddinge, Karolinska Institutet, SE-141 86
Stockholm, Sweden
| | - Jamie D Feusner
- Department of Psychiatry and Biobehavioral Sciences, University of
California Los Angeles, Los Angeles, CA 90095, USA
| | - Ivanka Savic-Berglund
- Department of Women's and Children's Health, Karolinska Institutet and
University Hospital, SE-171 76 Stockholm, Sweden
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49
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Association between abnormal serum myelin-specific protein levels and white matter integrity in first-episode and drug-naïve patients with major depressive disorder. J Affect Disord 2018; 232:61-68. [PMID: 29477585 DOI: 10.1016/j.jad.2018.02.044] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Revised: 12/01/2017] [Accepted: 02/15/2018] [Indexed: 11/20/2022]
Abstract
BACKGROUND Although the structural abnormalities of white matter (WM) have been described in patients with major depressive disorder (MDD), the neuropathological changes remain unclear. The current study aimed to investigate the myelin oligodendrocyte glycoprotein (MOG) and myelin-associated glycoprotein (MAG) levels and their correlations with WM integrity in first-episode, drug-naïve MDD patients. METHODS We obtained diffusion tensor images of 102 first-episode, drug-naïve MDD patients and 81 age- and sex-matched controls. Serum MOG and MAG levels of all participants were measured and compared between the two groups. The correlations between WM integrity and MOG and MAG levels were examined. RESULTS MOG and MAG serum levels were significantly higher in MDD patients than in controls. Patients with MDD also showed decreased fractional anisotropy (FA) and axial diffusivity in the WM of the bilateral thalamus, right hippocampus, right temporal lobe, and left pulvinar. At the whole-brain level, no regions showed any correlations of diffusivity parameters with MOG or MAG levels in healthy subjects. However, we observed two-way correlations between the MOG and MAG levels and the FA and mean diffusivity values in the WM of the left middle frontal lobe, right inferior parietal lobe, and right supplementary motor area in MDD patients. LIMITATIONS Further investigation with a larger sample size and longitudinal studies are required to better understand the neuropathology of WM integrity in MDD. CONCLUSIONS Our findings represent the first evidence of a relationship between abnormal serum myelin-specific protein levels and impaired WM integrity, which may help to better understand the neurobiological mechanisms of MDD.
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50
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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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