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Kang B, Ma J, Shen J, Zhao C, Hua X, Qiu G, A X, Xu H, Xu J, Xiao L. Hemisphere lateralization of graph theoretical network in end-stage knee osteoarthritis patients. Brain Res Bull 2024; 213:110976. [PMID: 38750971 DOI: 10.1016/j.brainresbull.2024.110976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 04/09/2024] [Accepted: 05/08/2024] [Indexed: 05/18/2024]
Abstract
Hemisphere functional lateralization is a prominent feature of the human brain. However, it is not known whether hemispheric lateralization features are altered in end-stage knee osteoarthritis (esKOA). In this study, we performed resting-state functional magnetic imaging on 46 esKOA patients and 31 healthy controls (HCs) and compared with the global and inter-hemisphere network to clarify the hemispheric functional network lateralization characteristics of patients. A correlation analysis was performed to explore the relationship between the inter-hemispheric network parameters and clinical features of patients. The node attributes were analyzed to explore the factors changing in the hemisphere network function lateralization in patients. We found that patients and HCs exhibited "small-world" brain network topology. Clustering coefficient increased in patients compared with that in HCs. The hemisphere difference in inter-hemispheric parameters including assortativity, global efficiency, local efficiency, clustering coefficients, small-worldness, and shortest path length. The pain course and intensity of esKOA were positively correlated with the right hemispheric lateralization in local efficiency, clustering coefficients, and the small-worldness, respectively. The significant alterations of several nodal properties were demonstrated within group in pain-cognition, pain-emotion, and pain regulation circuits. The abnormal lateralization inter-hemisphere network may be caused by the destruction of regional network properties.
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Affiliation(s)
- Bingxin Kang
- Rehabilitation Treatment Centre, The First Affiliated Hospital of Henan University of Chinese Medicine, Zhengzhou, China
| | - Jie Ma
- Center of Rehabilitation Medicine, Shanghai University of Traditional Chinese Medicine Yueyang Hospital of Integrated Traditional Chinese Medicine and Western Medicine, Shanghai, China
| | - Jun Shen
- Shanghai Guanghua Hospital of Integrative Chinese and Western Medicine, Shanghai, China
| | - Chi Zhao
- Acupuncture Tuina Institute, Henan University of Chinese Medicine, Zhengzhou, China
| | - Xuyun Hua
- Center of Rehabilitation Medicine, Shanghai University of Traditional Chinese Medicine Yueyang Hospital of Integrated Traditional Chinese Medicine and Western Medicine, Shanghai, China
| | - Guowei Qiu
- Shanghai Guanghua Hospital of Integrative Chinese and Western Medicine, Shanghai, China
| | - Xinyu A
- Shanghai Guanghua Hospital of Integrative Chinese and Western Medicine, Shanghai, China
| | - Hui Xu
- Acupuncture Tuina Institute, Henan University of Chinese Medicine, Zhengzhou, China
| | - Jianguang Xu
- Rehabilitation Science, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
| | - Lianbo Xiao
- Shanghai Guanghua Hospital of Integrative Chinese and Western Medicine, No. 540 Xinhua Road, Shanghai 200052, China.
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2
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Fernández R, Ramírez K, Lorente-Bermúdez R, Gómez-Gil E, Mora M, Guillamon A, Pásaro E. Analysis of single nucleotide polymorphisms of the metabotropic glutamate receptors in a transgender population. Front Endocrinol (Lausanne) 2024; 15:1382861. [PMID: 38919484 PMCID: PMC11196815 DOI: 10.3389/fendo.2024.1382861] [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: 02/06/2024] [Accepted: 05/21/2024] [Indexed: 06/27/2024] Open
Abstract
Introduction Gender incongruence (GI) is characterized by a marked incongruence between an individual's experienced/expressed gender and the assigned sex at birth. It includes strong displeasure about his or her sexual anatomy and secondary sex characteristics. In some people, this condition produces a strong distress with anxiety and depression named gender dysphoria (GD). This condition appears to be associated with genetic, epigenetics, hormonal as well as social factors. Given that L-glutamate is the major excitatory neurotransmitter in the central nervous system, also associated with male sexual behavior as well as depression, we aimed to determine whether metabotropic glutamate receptors are involved in GD. Methods We analyzed 74 single nucleotide polymorphisms located at the metabotropic glutamate receptors (mGluR1, mGluR3, mGluR4, mGluR5, mGluR7 and mGluR8) in 94 transgender versus 94 cisgender people. The allele and genotype frequencies were analyzed by c2 test contrasting male and female cisgender and transgender populations. The strength of the associations was measured by binary logistic regression, estimating the odds ratio (OR) for each genotype. Measurement of linkage disequilibrium, and subsequent measurement of haplotype frequencies were also performed considering three levels of significance: P ≤ 0.05, P ≤ 0.005 and P ≤ 0.0005. Furthermore, false positives were controlled with the Bonferroni correction (P ≤ 0.05/74 = 0.00067). Results After analysis of allele and genotypic frequencies, we found twenty-five polymorphisms with significant differences at level P ≤ 0.05, five at P ≤ 0.005 and two at P ≤ 0.0005. Furthermore, the only two polymorphisms (rs9838094 and rs1818033) that passed the Bonferroni correction were both related to the metabotropic glutamate receptor 7 (mGluR7) and showed significant differences for multiple patterns of inheritance. Moreover, the haplotype T/G [OR=0.34 (0.19-0.62); P<0.0004] had a lower representation in the transgender population than in the cisgender population, with no evidence of sex cross-interaction. Conclusion We provide genetic evidence that the mGluR7, and therefore glutamatergic neurotransmission, may be involved in GI and GD.
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Affiliation(s)
- Rosa Fernández
- Department of Psychology, Interdisciplinary Center for Chemistry and Biology Institute, Centro Interdisciplinar de Química e Bioloxía (CICA), Diagnóstico Conductual y Molecular Aplicado a la Salud (DICOMOSA) Group, University of A Coruña, A Coruña, Spain
- Department of Psychology, Institute for Biomedical Research of A Coruña (INIBIC), A Coruña, Spain
| | - Karla Ramírez
- Department of Psychology, Interdisciplinary Center for Chemistry and Biology Institute, Centro Interdisciplinar de Química e Bioloxía (CICA), Diagnóstico Conductual y Molecular Aplicado a la Salud (DICOMOSA) Group, University of A Coruña, A Coruña, Spain
- Department of Psychology, Institute for Biomedical Research of A Coruña (INIBIC), A Coruña, Spain
| | - Roberto Lorente-Bermúdez
- Department of Psychology, Interdisciplinary Center for Chemistry and Biology Institute, Centro Interdisciplinar de Química e Bioloxía (CICA), Diagnóstico Conductual y Molecular Aplicado a la Salud (DICOMOSA) Group, University of A Coruña, A Coruña, Spain
| | - Esther Gómez-Gil
- Gender Identity Unit, Psychiatry Service, Institute of Neurosciences, Hospital Clínic Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Mireia Mora
- Department of Endocrinology and Nutrition, Hospital Clínic Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Antonio Guillamon
- Department of Psychobiology, Faculty of Psychology, National University of Distance Education (UNED), Madrid, Spain
| | - Eduardo Pásaro
- Department of Psychology, Interdisciplinary Center for Chemistry and Biology Institute, Centro Interdisciplinar de Química e Bioloxía (CICA), Diagnóstico Conductual y Molecular Aplicado a la Salud (DICOMOSA) Group, University of A Coruña, A Coruña, Spain
- Department of Psychology, Institute for Biomedical Research of A Coruña (INIBIC), A Coruña, Spain
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3
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Luckhoff HK, Smit R, Phahladira L, du Plessis, Emsley R, Asmal L. Sex versus gender associations with brain structure. J Clin Neurosci 2024; 122:103-109. [PMID: 38493700 DOI: 10.1016/j.jocn.2024.03.009] [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: 10/24/2023] [Revised: 01/22/2024] [Accepted: 03/13/2024] [Indexed: 03/19/2024]
Abstract
In contrast to sex (a biological distinction), little is known about the associations between gender (a societal construct) and brain structure in the general population. In response to this knowledge gap, we examined the associations of sex vs. gender with FreeSurfer-generated cortical thickness and proportion-adjusted subcortical brain volume regions-of-interest (ROIs) in healthy adults (n = 88) screened for general medical conditions, mental illness, substance abuse, and intracranial pathologies. Gender role endorsement was assessed using the well-established and validated Bem Sex Role Inventory. For our main objectives, we calculated a continuum score as a composite measure of gender. For our secondary objectives, we examined sex-specific associations of the masculine vs. feminine gender role endorsement domains with brain structural outcomes. We found that female sex, independent of continuum scores, was associated with larger proportion-adjusted volumes for the basal ganglia, hippocampus, and ventral diencephalon. Higher continuum scores, independent of sex, were associated with thicker cortical thickness for the left and right superior frontal cortex, caudal and rostral middle frontal cortex, and right pars orbitalis. Female sex and higher continuum scores were independently associated with larger corpus callosum volumes. Post-hoc testing showed sex-specific associations between higher femininity scores and thicker prefrontal cortical thickness for the ROIs in females, but not in males. In conclusion, sex and gender showed semi-independent associations with brain structure in a general population sample. Our research supports the disaggregation of sex and gender to provide a more nuanced perspective on brain structural differences between men and women.
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Affiliation(s)
- H K Luckhoff
- Department of Psychiatry, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa.
| | - R Smit
- Department of Psychiatry, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - L Phahladira
- Department of Psychiatry, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - du Plessis
- Department of Psychiatry, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - R Emsley
- Department of Psychiatry, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - L Asmal
- Department of Psychiatry, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
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4
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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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5
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Fernández R, Zubiaurre-Elorza L, Santisteban A, Ojeda N, Collet S, Kiyar M, T'Sjoen G, Mueller SC, Guillamon A, Pásaro E. CBLL1 is hypomethylated and correlates with cortical thickness in transgender men before gender affirming hormone treatment. Sci Rep 2023; 13:21609. [PMID: 38062063 PMCID: PMC10703770 DOI: 10.1038/s41598-023-48782-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 11/30/2023] [Indexed: 12/18/2023] Open
Abstract
Gender identity refers to the consciousness of being a man, a woman or other condition. Although it is generally congruent with the sex assigned at birth, for some people it is not. If the incongruity is distressing, it is defined as gender dysphoria (GD). Here, we measured whole-genome DNA methylation by the Illumina © Infinium Human Methylation 850k array and reported its correlation with cortical thickness (CTh) in 22 transgender men (TM) experiencing GD versus 25 cisgender men (CM) and 28 cisgender women (CW). With respect to the methylation analysis, TM vs. CW showed significant differences in 35 CpGs, while 2155 CpGs were found when TM vs. CM were compared. With respect to correlation analysis, TM showed differences in methylation of CBLL1 and DLG1 genes that correlated with global and left hemisphere CTh. Both genes were hypomethylated in TM compared to the cisgender groups. Early onset TM showed a positive correlation between CBLL1 and several cortical regions in the frontal (left caudal middle frontal), temporal (right inferior temporal, left fusiform) and parietal cortices (left supramarginal and right paracentral). This is the first study relating CBLL1 methylation with CTh in transgender persons and supports a neurodevelopmental hypothesis of gender identity.
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Affiliation(s)
- Rosa Fernández
- Centro Interdisciplinar de Química E Bioloxía - CICA. Departamento de Psicología, Universidade da Coruña, Grupo DICOMOSA, Campus Elviña S/N, 15071, A Coruña, Spain.
- Instituto de Investigación Biomédica de A Coruña (INIBIC), 15071, Oza, A Coruña, Spain.
| | - Leire Zubiaurre-Elorza
- Departamento de Psicología, Facultad de Ciencias de la Salud, Universidad de Deusto, Bilbao, Spain
| | - Andrea Santisteban
- Centro Interdisciplinar de Química E Bioloxía - CICA. Departamento de Psicología, Universidade da Coruña, Grupo DICOMOSA, Campus Elviña S/N, 15071, A Coruña, Spain
| | - Natalia Ojeda
- Departamento de Psicología, Facultad de Ciencias de la Salud, Universidad de Deusto, Bilbao, Spain
| | - Sarah Collet
- Department of Endocrinology, Ghent University Hospital, 9000, Ghent, Belgium
| | - Meltem Kiyar
- Department of Experimental Clinical and Health Psychology, Ghent University, 9000, Ghent, Belgium
| | - Guy T'Sjoen
- Department of Endocrinology, Center for Sexology and Gender, Ghent University Hospital, 9000, Ghent, Belgium
| | - Sven C Mueller
- Department of Experimental Clinical and Health Psychology, Ghent University, 9000, Ghent, Belgium
| | - Antonio Guillamon
- Departamento de Psicobiología, Facultad de Psicología, Universidad Nacional de Educación a Distancia, 28040, Madrid, Spain.
| | - Eduardo Pásaro
- Centro Interdisciplinar de Química E Bioloxía - CICA. Departamento de Psicología, Universidade da Coruña, Grupo DICOMOSA, Campus Elviña S/N, 15071, A Coruña, Spain
- Instituto de Investigación Biomédica de A Coruña (INIBIC), 15071, Oza, A Coruña, Spain
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6
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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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7
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Wiersch L, Hamdan S, Hoffstaedter F, Votinov M, Habel U, Clemens B, Derntl B, Eickhoff SB, Patil KR, Weis S. Accurate sex prediction of cisgender and transgender individuals without brain size bias. Sci Rep 2023; 13:13868. [PMID: 37620339 PMCID: PMC10449927 DOI: 10.1038/s41598-023-37508-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 06/22/2023] [Indexed: 08/26/2023] Open
Abstract
The increasing use of machine learning approaches on neuroimaging data comes with the important concern of confounding variables which might lead to biased predictions and in turn spurious conclusions about the relationship between the features and the target. A prominent example is the brain size difference between women and men. This difference in total intracranial volume (TIV) can cause bias when employing machine learning approaches for the investigation of sex differences in brain morphology. A TIV-biased model will not capture qualitative sex differences in brain organization but rather learn to classify an individual's sex based on brain size differences, thus leading to spurious and misleading conclusions, for example when comparing brain morphology between cisgender- and transgender individuals. In this study, TIV bias in sex classification models applied to cis- and transgender individuals was systematically investigated by controlling for TIV either through featurewise confound removal or by matching the training samples for TIV. Our results provide strong evidence that models not biased by TIV can classify the sex of both cis- and transgender individuals with high accuracy, highlighting the importance of appropriate modeling to avoid bias in automated decision making.
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Affiliation(s)
- Lisa Wiersch
- Institute of Systems Neuroscience, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Institute of Neuroscience and Medicine (INM-7: Brain and Behaviour), Research Centre Jülich, Jülich, Germany
| | - Sami Hamdan
- Institute of Systems Neuroscience, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Institute of Neuroscience and Medicine (INM-7: Brain and Behaviour), Research Centre Jülich, Jülich, Germany
| | - Felix Hoffstaedter
- Institute of Systems Neuroscience, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Institute of Neuroscience and Medicine (INM-7: Brain and Behaviour), Research Centre Jülich, Jülich, Germany
| | - Mikhail Votinov
- Department of Psychiatry, Psychotherapy and Psychosomatics, Faculty of Medicine, RWTH Aachen University, Aachen, Germany
- Institute of Neuroscience and Medicine (INM-10: Brain Structure-Function Relationships), Research Centre Jülich, Jülich, Germany
| | - Ute Habel
- Department of Psychiatry, Psychotherapy and Psychosomatics, Faculty of Medicine, RWTH Aachen University, Aachen, Germany
- Institute of Neuroscience and Medicine (INM-10: Brain Structure-Function Relationships), Research Centre Jülich, Jülich, Germany
| | - Benjamin Clemens
- Department of Psychiatry, Psychotherapy and Psychosomatics, Faculty of Medicine, RWTH Aachen University, Aachen, Germany
- Institute of Neuroscience and Medicine (INM-10: Brain Structure-Function Relationships), Research Centre Jülich, Jülich, Germany
| | - Birgit Derntl
- Department of Psychiatry and Psychotherapy, Tübingen Center for Mental Health, University of Tübingen, Tübingen, Germany
- LEAD Graduate School and Research Network, University of Tübingen, Tübingen, Germany
| | - Simon B Eickhoff
- Institute of Systems Neuroscience, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Institute of Neuroscience and Medicine (INM-7: Brain and Behaviour), Research Centre Jülich, Jülich, Germany
| | - Kaustubh R Patil
- Institute of Systems Neuroscience, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
- Institute of Neuroscience and Medicine (INM-7: Brain and Behaviour), Research Centre Jülich, Jülich, Germany.
| | - Susanne Weis
- Institute of Systems Neuroscience, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
- Institute of Neuroscience and Medicine (INM-7: Brain and Behaviour), Research Centre Jülich, Jülich, Germany.
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Reed MB, Handschuh PA, Klöbl M, Konadu ME, Kaufmann U, Hahn A, Kranz GS, Spies M, Lanzenberger R. The influence of sex steroid treatment on insular connectivity in gender dysphoria. Psychoneuroendocrinology 2023; 155:106336. [PMID: 37499299 DOI: 10.1016/j.psyneuen.2023.106336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 07/16/2023] [Accepted: 07/17/2023] [Indexed: 07/29/2023]
Abstract
BACKGROUND Sex-specific differences in brain connectivity were found in various neuroimaging studies, though little is known about sex steroid effects on insular functioning. Based on well-characterized sex differences in emotion regulation, interoception and higher-level cognition, gender-dysphoric individuals receiving gender-affirming hormone therapy represent an interesting cohort to investigate how sex hormones might influence insular connectivity and related brain functions. METHODS To analyze the potential effect of sex steroids on insular connectivity at rest, 11 transgender women, 14 transgender men, 20 cisgender women, and 11 cisgender men were recruited. All participants underwent two magnetic resonance imaging sessions involving resting-state acquisitions separated by a median time period of 4.5 months and also completed the Bermond-Vorst alexithymia questionnaire at the initial and final examination. Between scans, transgender subjects received gender-affirming hormone therapy. RESULTS A seed based functional connectivity analysis revealed a significant 2-way interaction effect of group-by-time between right insula, cingulum, left middle frontal gyrus and left angular gyrus. Post-hoc tests demonstrated an increase in connectivity for transgender women when compared to cisgender men. Furthermore, spectral dynamic causal modelling showed reduced effective connectivity from the posterior cingulum and left angular gyrus to the left middle frontal gyrus as well as from the right insula to the left middle frontal gyrus. Alexithymia changes were found after gender-affirming hormone therapy for transgender women in both fantasizing and identifying. CONCLUSION These findings suggest a considerable influence of estrogen administration and androgen suppression on brain networks implicated in interoception, own-body perception and higher-level cognition.
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Affiliation(s)
- Murray B Reed
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - Patricia A Handschuh
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - Manfred Klöbl
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - Melisande E Konadu
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - Ulrike Kaufmann
- Department of Obstetrics and Gynecology, Medical University of Vienna, Austria
| | - Andreas Hahn
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - Georg S Kranz
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria; Department of Rehabilitation Sciences, Hong Kong Polytechnic University, Hong Kong, China
| | - Marie Spies
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - Rupert Lanzenberger
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria.
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9
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van Heesewijk J, Steenwijk MD, Kreukels BPC, Veltman DJ, Bakker J, Burke SM. Alterations in the inferior fronto-occipital fasciculus - a specific neural correlate of gender incongruence? Psychol Med 2023; 53:3461-3470. [PMID: 35301969 PMCID: PMC10277722 DOI: 10.1017/s0033291721005547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 11/06/2021] [Accepted: 12/28/2021] [Indexed: 11/05/2022]
Abstract
BACKGROUND Increasing numbers of adolescents seek help for gender-identity questions. Consequently, requests for medical treatments, such as puberty suppression, are growing. However, studies investigating the neurobiological substrate of gender incongruence (when birth-assigned sex and gender identity do not align) are scarce, and knowledge about the effects of puberty suppression on the developing brain of transgender youth is limited. METHODS Here we cross-sectionally investigated sex and gender differences in regional fractional anisotropy (FA) as measured by diffusion MR imaging, and the impact of puberty on alterations in the white-matter organization of 35 treatment-naive prepubertal children and 41 adolescents with gender incongruence, receiving puberty suppression. The transgender groups were compared with 79 age-matched, treatment-naive cisgender (when sex and gender align) peers. RESULTS We found that transgender adolescents had lower FA in the bilateral inferior fronto-occipital fasciculus (IFOF), forceps major and corpus callosum than cisgender peers. In addition, average FA values of the right IFOF correlated negatively with adolescents' cumulative dosage of puberty suppressants received. Of note, prepubertal children also showed significant FA group differences in, again, the right IFOF and left cortico-spinal tract, but with the reverse pattern (transgender > cisgender) than was seen in adolescents. CONCLUSIONS Importantly, our results of lower FA (indexing less longitudinal organization, fiber coherence, and myelination) in the IFOF of gender-incongruent adolescents replicate prior findings in transgender adults, suggesting a salient neural correlate of gender incongruence. Findings highlight the complexity with which (pubertal) sex hormones impact white-matter development and add important insight into the neurobiological substrate associated with gender incongruence.
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Affiliation(s)
- Jason van Heesewijk
- Center of Expertise on Gender Dysphoria, Amsterdam University Medical Centers, location VUmc, De Boelelaan 1131, Amsterdam, Noord-Holland, Netherlands
| | - Martijn D. Steenwijk
- Center of Expertise on Gender Dysphoria, Amsterdam University Medical Centers, location VUmc, De Boelelaan 1131, Amsterdam, Noord-Holland, Netherlands
| | - Baudewijntje P. C. Kreukels
- Center of Expertise on Gender Dysphoria, Amsterdam University Medical Centers, location VUmc, De Boelelaan 1131, Amsterdam, Noord-Holland, Netherlands
| | - Dick J. Veltman
- Center of Expertise on Gender Dysphoria, Amsterdam University Medical Centers, location VUmc, De Boelelaan 1131, Amsterdam, Noord-Holland, Netherlands
| | - Julie Bakker
- Center of Expertise on Gender Dysphoria, Amsterdam University Medical Centers, location VUmc, De Boelelaan 1131, Amsterdam, Noord-Holland, Netherlands
| | - Sarah M. Burke
- Center of Expertise on Gender Dysphoria, Amsterdam University Medical Centers, location VUmc, De Boelelaan 1131, Amsterdam, Noord-Holland, Netherlands
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10
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Strang JF, McClellan LS, Li S, Jack AE, Wallace GL, McQuaid GA, Kenworthy L, Anthony LG, Lai MC, Pelphrey KA, Thalberg AE, Nelson EE, Phan JM, Sadikova E, Fischbach AL, Thomas J, Vaidya CJ. The autism spectrum among transgender youth: default mode functional connectivity. Cereb Cortex 2023; 33:6633-6647. [PMID: 36721890 PMCID: PMC10233301 DOI: 10.1093/cercor/bhac530] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 12/19/2022] [Accepted: 12/20/2022] [Indexed: 02/02/2023] Open
Abstract
The common intersection of autism and transgender identities has been described in clinical and community contexts. This study investigates autism-related neurophenotypes among transgender youth. Forty-five transgender youth, evenly balanced across non-autistic, slightly subclinically autistic, and full-criteria autistic subgroupings, completed resting-state functional magnetic resonance imaging to examine functional connectivity. Results confirmed hypothesized default mode network (DMN) hub hyperconnectivity with visual and motor networks in autism, partially replicating previous studies comparing cisgender autistic and non-autistic adolescents. The slightly subclinically autistic group differed from both non-autistic and full-criteria autistic groups in DMN hub connectivity to ventral attention and sensorimotor networks, falling between non-autistic and full-criteria autistic groups. Autism traits showed a similar pattern to autism-related group analytics, and also related to hyperconnectivity between DMN hub and dorsal attention network. Internalizing, gender dysphoria, and gender minority-related stigma did not show connectivity differences. Connectivity differences within DMN followed previously reported patterns by designated sex at birth (i.e. female birth designation showing greater within-DMN connectivity). Overall, findings suggest behavioral diagnostics and autism traits in transgender youth correspond to observable differences in DMN hub connectivity. Further, this study reveals novel neurophenotypic characteristics associated with slightly subthreshold autism, highlighting the importance of research attention to this group.
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Affiliation(s)
- John F Strang
- Gender and Autism Program, Children’s National Hospital, 15245 Shady Grove Road, Suite 350, Rockville, MD 20850, USA
- Departments of Pediatrics, Psychiatry, and Behavioral Sciences, George Washington University School of Medicine, Washington, DC, USA
- Division of Neuropsychology, Children’s National Hospital, Washington, DC, USA
| | - Lucy S McClellan
- Division of Neuropsychology, Children’s National Hospital, Washington, DC, USA
| | - Sufang Li
- Department of Psychology, Georgetown University, Washington, DC, USA
| | - Allison E Jack
- Department of Psychology, George Mason University, Fairfax, VA, USA
| | - Gregory L Wallace
- Department of Speech, Language, & Hearing Sciences, George Washington University, Washington, DC, USA
| | - Goldie A McQuaid
- Department of Psychology, George Mason University, Fairfax, VA, USA
| | - Lauren Kenworthy
- Departments of Pediatrics, Psychiatry, and Behavioral Sciences, George Washington University School of Medicine, Washington, DC, USA
- Division of Neuropsychology, Children’s National Hospital, Washington, DC, USA
| | - Laura G Anthony
- Department of Psychiatry and Behavioral Sciences, University of Colorado School of Medicine, Aurora, CO, USA
| | - Meng-Chuan Lai
- Child and Youth Mental Health Collaborative at the Centre for Addiction and Mental Health, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Kevin A Pelphrey
- Department of Neurology, University of Virginia Medical School, Charlottesville, VA, USA
| | | | - Eric E Nelson
- Center for Biobehavioral Health, The Research Institute at Nationwide Children’s Hospital, Columbus, OH, USA
| | - Jenny M Phan
- Division of Neuropsychology, Children’s National Hospital, Washington, DC, USA
| | - Eleonora Sadikova
- School of Education and Human Development, University of Virginia, Charlottesville, VA, USA
| | - Abigail L Fischbach
- Division of Neuropsychology, Children’s National Hospital, Washington, DC, USA
| | | | - Chandan J Vaidya
- Department of Psychology, Georgetown University, Washington, DC, USA
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11
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Edmiston EK, Juster RP. Refining Research and Representation of Sexual and Gender Diversity in Neuroscience. BIOLOGICAL PSYCHIATRY. COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2022; 7:1251-1257. [PMID: 35940568 DOI: 10.1016/j.bpsc.2022.07.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 07/13/2022] [Accepted: 07/20/2022] [Indexed: 06/15/2023]
Abstract
There are opportunities to improve neuroscience that include lesbian, gay, bisexual, and transgender (LGBT) people. In this review, we briefly describe how the history of LGBT people in psychiatry has influenced neuroimaging approaches; how these attitudes have shifted over time; and what we can do to ensure that our future work is rigorous, ethical, and in service of the LGBT community. We suggest ways to refine neuroimaging methodologies to improve our understanding of marginalization and stigma while shifting away from research that focuses solely on the "etiology" or origins of LGBT identities. We also offer suggestions for conducting representative research that is LGBT-inclusive, regardless of the population of interest.
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Affiliation(s)
- Elliot Kale Edmiston
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.
| | - Robert-Paul Juster
- Department of Psychiatry and Addiction, University of Montreal, Montreal, Quebec, Canada; Research Center of the Montreal Mental Health University Institute, Montreal, Quebec, Canada
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12
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Anderson D, Wijetunge H, Moore P, Provenzano D, Li N, Hasoon J, Viswanath O, Kaye AD, Urits I. Gender Dysphoria and Its Non-Surgical and Surgical Treatments. Health Psychol Res 2022; 10:38358. [PMID: 36168640 PMCID: PMC9501960 DOI: 10.52965/001c.38358] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2023] Open
Abstract
Gender dysphoria is defined by severe or persistent distress associated with an incongruence between one's gender identity and biological sex. It is estimated that 1.4 million Americans and 25 million people worldwide identify as transgender and that 0.6% of Americans experience gender dysphoria. The pathophysiology of gender dysphoria is multifactorial and incompletely understood. Genetics, androgen exposure, neuroanatomy, brain connectivity, history of trauma, parents with psychological disorders, and being raised by less than two parents are associated with gender dysphoria. Gender dysphoria most frequently presents in early teenage years but can present earlier or later. Anxiety and depression are the two most common comorbid diagnoses and may be the reason for presentation to medical care. Diagnosis is established through history and or validated questionnaires. Treatment includes psychosocial therapy, pharmacotherapy for underlying depression and/or anxiety, hormonal therapy, non-genital and/or genital feminization or masculinization operations. The frequency and severity of treatment related morbidity increases progressively as treatments go from conservative to more invasive. Gender dysphoria and its treatment is individualized and not completely understood.
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Affiliation(s)
| | - Himasa Wijetunge
- School of Medicine, Louisiana State University Health Sciences Center
| | - Peyton Moore
- School of Medicine, Louisiana State University Health Science Center
| | - Daniel Provenzano
- School of Medicine, Louisiana State University Health Sciences Center
| | - Nathan Li
- Medical School, Medical College of Wisconsin
| | - Jamal Hasoon
- Anesthesiology, Beth Israel Deaconess Medical Center, Harvard Medical School
| | - Omar Viswanath
- School of Medicine, Louisiana State University Health Sciences Center
| | - Alan D Kaye
- School of Medicine, Louisiana State University Health Sciences Center
| | - Ivan Urits
- School of Medicine, Louisiana State University Health Sciences Center
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13
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Skorska MN, Lobaugh NJ, Lombardo MV, van Bruggen N, Chavez S, Thurston LT, Aitken M, Zucker KJ, Chakravarty MM, Lai MC, VanderLaan DP. Inter-Network Brain Functional Connectivity in Adolescents Assigned Female at Birth Who Experience Gender Dysphoria. Front Endocrinol (Lausanne) 2022; 13:903058. [PMID: 35937791 PMCID: PMC9353716 DOI: 10.3389/fendo.2022.903058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 06/15/2022] [Indexed: 11/13/2022] Open
Abstract
Gender dysphoria (GD) is characterized by distress due to an incongruence between experienced gender and sex assigned at birth. Brain functional connectivity in adolescents who experience GD may be associated with experienced gender (vs. assigned sex) and/or brain networks implicated in own-body perception. Furthermore, sexual orientation may be related to brain functional organization given commonalities in developmental mechanisms proposed to underpin GD and same-sex attractions. Here, we applied group independent component analysis to resting-state functional magnetic resonance imaging (rs-fMRI) BOLD timeseries data to estimate inter-network (i.e., between independent components) timeseries correlations, representing functional connectivity, in 17 GD adolescents assigned female at birth (AFAB) not receiving gender-affirming hormone therapy, 17 cisgender girls, and 15 cisgender boys (ages 12-17 years). Sexual orientation was represented by degree of androphilia-gynephilia and sexual attractions strength. Multivariate partial least squares analyses found that functional connectivity differed among cisgender boys, cisgender girls, and GD AFAB, with the largest difference between cisgender boys and GD AFAB. Regarding sexual orientation and age, the brain's intrinsic functional organization of GD AFAB was both similar to and different from cisgender girls, and both differed from cisgender boys. The pattern of group differences and the networks involved aligned with the hypothesis that brain functional organization is different among GD AFAB (vs. cisgender) adolescents, and certain aspects of this organization relate to brain areas implicated in own-body perception and self-referential thinking. Overall, brain functional organization of GD AFAB was generally more similar to that of cisgender girls than cisgender boys.
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Affiliation(s)
- Malvina N. Skorska
- Child and Youth Psychiatry, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Nancy J. Lobaugh
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Medicine, Division of Neurology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Michael V. Lombardo
- Laboratory for Autism and Neurodevelopmental Disorders, Center for Neuroscience and Cognitive Systems @UniTn, Istituto Italiano di Tecnologia, Rovereto, Italy
| | - Nina van Bruggen
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON, Canada
| | - Sofia Chavez
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Lindsey T. Thurston
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON, Canada
| | - Madison Aitken
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Kenneth J. Zucker
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - M. Mallar Chakravarty
- Cerebral Imaging Centre, Douglas Mental Health University Institute, Montreal, PQ, Canada
- Department of Psychiatry, McGill University, Montreal, PQ, Canada
- Department of Biological and Biomedical Engineering, McGill University, Montreal, PQ, Canada
| | - Meng-Chuan Lai
- Child and Youth Psychiatry, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- The Margaret and Wallace McCain Centre for Child, Youth & Family Mental Health and Azrieli Adult Neurodevelopmental Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychiatry and Autism Research Unit, The Hospital for Sick Children, Toronto, ON, Canada
- Department of Psychiatry, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan
- Autism Research Centre, Department of Psychiatry, University of Cambridge, Cambridge, United Kingdom
| | - Doug P. VanderLaan
- Child and Youth Psychiatry, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON, Canada
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14
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Fortunato A, Giovanardi G, Innocenzi E, Mirabella M, Caviglia G, Lingiardi V, Speranza AM. Is It Autism? A Critical Commentary on the Co-Occurrence of Gender Dysphoria and Autism Spectrum Disorder. JOURNAL OF HOMOSEXUALITY 2022; 69:1204-1221. [PMID: 33852376 DOI: 10.1080/00918369.2021.1905385] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
An increasing amount of literature revealed a link between GD and ASD. Both GD and ASD are complex and heterogeneous conditions characterized by a large variety of presentations. Studies have reported that individuals with GD tend to have higher prevalence rates of autistic traits in comparison to the general population. The purpose of this commentary is to provide, through the description of a clinical case, our reading and a possible interpretation of the correlation of these two conditions in light of the several methodological limitations found in literature. We hypothesize that the traits often classified as autistic could be more accurately related to the distress and discomfort evoked by GD. The autistic traits of individuals with GD as forms of psychological defenses and coping mechanisms aimed at dealing with socio-relational and identity problems are discussed.
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Affiliation(s)
- Alexandro Fortunato
- Department of Dynamic and Clinical Psychology, and Health Studies, "Sapienza," University of Rome, Italy
| | - Guido Giovanardi
- Department of Psychology, University of Campania, "Luigi Vanvitelli," University of Caserta, Italy
| | - Eleonora Innocenzi
- Department of Letters and Philosophy, "Tor Vergata," University of Rome, Italy
| | - Marta Mirabella
- Department of Dynamic and Clinical Psychology, and Health Studies, "Sapienza," University of Rome, Italy
| | - Giorgio Caviglia
- Department of Psychology, University of Campania, "Luigi Vanvitelli," University of Caserta, Italy
| | - Vittorio Lingiardi
- Department of Dynamic and Clinical Psychology, and Health Studies, "Sapienza," University of Rome, Italy
| | - Anna Maria Speranza
- Department of Dynamic and Clinical Psychology, and Health Studies, "Sapienza," University of Rome, Italy
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15
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Uribe C, Escrichs A, de Filippi E, Sanz-Perl Y, Junque C, Gomez-Gil E, Kringelbach ML, Guillamon A, Deco G. Whole-brain dynamics differentiate among cisgender and transgender individuals. Hum Brain Mapp 2022; 43:4103-4115. [PMID: 35583382 PMCID: PMC9374880 DOI: 10.1002/hbm.25905] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Revised: 04/25/2022] [Accepted: 04/28/2022] [Indexed: 11/08/2022] Open
Abstract
How the brain represents gender identity is largely unknown, but some neural differences have recently been discovered. We used an intrinsic ignition framework to investigate whether there are gender differences in the propagation of neural activity across the whole-brain and within resting-state networks. Studying 29 trans men and 17 trans women with gender incongruence, 22 cis women, and 19 cis men, we computed the capability of a given brain area in space to propagate activity to other areas (mean-ignition), and the variability across time for each brain area (node-metastability). We found that both measurements differentiated all groups across the whole brain. At the network level, we found that compared to the other groups, cis men showed higher mean-ignition of the dorsal attention network and node-metastability of the dorsal and ventral attention, executive control, and temporal parietal networks. We also found higher mean-ignition values in cis men than in cis women within the executive control network, but higher mean-ignition in cis women than cis men and trans men for the default mode. Node-metastability was higher in cis men than cis women in the somatomotor network, while both mean-ignition and node-metastability were higher for cis men than trans men in the limbic network. Finally, we computed correlations between these measurements and a body image satisfaction score. Trans men's dissatisfaction as well as cis men's and cis women's satisfaction toward their own body image were distinctively associated with specific networks in each group. Overall, the study of the whole-brain network dynamical complexity discriminates gender identity groups, functional dynamic approaches could help disentangle the complex nature of the gender dimension in the brain.
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Affiliation(s)
- Carme Uribe
- Unitat de Psicologia Medica, Departament de Medicina, Institute of Neuroscience, Universitat de Barcelona, Barcelona, Spain.,Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona, Spain.,Research Imaging Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health (CAMH), University of Toronto, Toronto, Canada
| | - Anira Escrichs
- Computational Neuroscience Group, Center for Brain and Cognition, Department of Information and Communication Technologies, Universitat Pompeu Fabra, Barcelona, Catalonia, Spain
| | - Eleonora de Filippi
- Computational Neuroscience Group, Center for Brain and Cognition, Department of Information and Communication Technologies, Universitat Pompeu Fabra, Barcelona, Catalonia, Spain
| | - Yonatan Sanz-Perl
- Computational Neuroscience Group, Center for Brain and Cognition, Department of Information and Communication Technologies, Universitat Pompeu Fabra, Barcelona, Catalonia, Spain
| | - Carme Junque
- Unitat de Psicologia Medica, Departament de Medicina, Institute of Neuroscience, Universitat de Barcelona, Barcelona, Spain.,Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | | | - Morten L Kringelbach
- Department of Psychiatry, University of Oxford, Oxford, UK.,Centre for Eudaimonia and Human Flourishing, University of Oxford, Oxford, UK.,Center for Music in the Brain, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Antonio Guillamon
- Departamento de Psicobiologia, Facultad de Psicologia, Universidad Nacional de Educacion a Distancia, Madrid, Spain
| | - Gustavo Deco
- Computational Neuroscience Group, Center for Brain and Cognition, Department of Information and Communication Technologies, Universitat Pompeu Fabra, Barcelona, Catalonia, Spain.,Institució Catalana de la Recerca i Estudis Avançats (ICREA), Barcelona, Catalonia, Spain.,Department of Neuropsychology, Max Planck Institute for human Cognitive and Brain Sciences, Leipzig, Germany.,Turner Institute for Brain and Mental Health, Monash University, Melbourne, Victoria, Australia
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16
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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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17
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Bakker J. The role of steroid hormones in the sexual differentiation of the human brain. J Neuroendocrinol 2022; 34:e13050. [PMID: 34708466 DOI: 10.1111/jne.13050] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 09/03/2021] [Accepted: 10/05/2021] [Indexed: 12/31/2022]
Abstract
Widespread sex differences in human brain structure and function have been reported. Research on animal models has demonstrated that sex differences in brain and behavior are induced by steroid hormones during specific, hormone sensitive, developmental periods. It was shown that typical male neural and behavioral characteristics develop under the influence of testosterone, mostly acting during perinatal development. By contrast, typical female neural and behavioral characteristics may actually develop under the influence of estradiol during a specific prepubertal period. This review provides an overview of our current knowledge on the role of steroid hormones in the sexual differentiation of the human brain. Both clinical and neuroimaging data obtained in patients with altered androgen levels/actions (i.e., congenital adrenal hyperplasia or complete androgen insensitivity syndrome [CAIS]), point to an important role of (prenatal) androgens in inducing typical male neural and psychosexual characteristics in humans. In contrast to rodents, there appears to be no obvious role for estrogens in masculinizing the human brain. Furthermore, data from CAIS also suggest a contribution of sex chromosome genes to the development of the human brain. The final part of this review is dedicated to a brief discussion of gender incongruence, also known as gender dysphoria, which has been associated with an altered or less pronounced sexual differentiation of the brain.
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Affiliation(s)
- Julie Bakker
- Neuroendocrinology, GIGA Neurosciences, Liège University, Liege, Belgium
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18
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Smith TC. Re-examining our roots: Queer history and anatomy. Anat Rec (Hoboken) 2022; 305:968-982. [PMID: 34997831 DOI: 10.1002/ar.24859] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 11/14/2021] [Accepted: 12/03/2021] [Indexed: 01/21/2023]
Abstract
Since its establishment as one of the major authorities on the human body, Anatomy has played a crucial role in social and political spheres. In this article, I review how the history of Anatomy has intersected with queer history and how the effects of these interactions have affected queer lives today. In these historical cases, I aim to demonstrate how Anatomy has affected the social organization of human culture and society and also how society has affected anatomical knowledge in return. As this reciprocal connection between Anatomy and societal organization is elucidated, I argue that anatomists, clinicians, and educators have an ethical duty to address the connections of this history, both in our research and our classrooms. This historical tour begins in the ancient world, which established a connection between sexuality and physiology and reproduction. This is followed by an exploration of the Renaissance and Enlightenment, which highlight the connections between anatomical knowledge, the law, and social organization. The progressive and modern eras are explored next via modern research into the anatomical and biological origins of same-sex attraction and the use of modern technology in these investigations. Finally, the article ends with a call for reform along with suggestions for future steps.
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Affiliation(s)
- Theodore C Smith
- Basic Sciences Department, College of Osteopathic Medicine, Touro University California, Vallejo, California, USA
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19
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Rainville JR, Lipuma T, Hodes GE. Translating the Transcriptome: Sex Differences in the Mechanisms of Depression and Stress, Revisited. Biol Psychiatry 2022; 91:25-35. [PMID: 33865609 PMCID: PMC10197090 DOI: 10.1016/j.biopsych.2021.02.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 02/01/2021] [Accepted: 02/01/2021] [Indexed: 12/28/2022]
Abstract
The past decade has produced a plethora of studies examining sex differences in the transcriptional profiles of stress and mood disorders. As we move forward from accepting the existence of extensive molecular sex differences in the brain to exploring the purpose of these sex differences, our approach must become more systemic and less reductionist. Earlier studies have examined specific brain regions and/or cell types. To use this knowledge to develop the next generation of personalized medicine, we need to comprehend how transcriptional changes across the brain and/or the body relate to each other. We provide an overview of the relationships between baseline and depression/stress-related transcriptional sex differences and explore contributions of preclinically identified mechanisms and their impacts on behavior.
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Affiliation(s)
- Jennifer R Rainville
- Department of Neuroscience, Virginia Polytechnic and State University, Blacksburg, Virginia
| | - Timothy Lipuma
- Department of Neuroscience, Virginia Polytechnic and State University, Blacksburg, Virginia
| | - Georgia E Hodes
- Department of Neuroscience, Virginia Polytechnic and State University, Blacksburg, Virginia.
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20
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Nicholson AA, Siegel M, Wolf J, Narikuzhy S, Roth SL, Hatchard T, Lanius RA, Schneider M, Lloyd CS, McKinnon MC, Heber A, Smith P, Lueger-Schuster B. A systematic review of the neural correlates of sexual minority stress: towards an intersectional minority mosaic framework with implications for a future research agenda. Eur J Psychotraumatol 2022; 13:2002572. [PMID: 35251527 PMCID: PMC8890555 DOI: 10.1080/20008198.2021.2002572] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND Systemic oppression, particularly towards sexual minorities, continues to be deeply rooted in the bedrock of many societies globally. Experiences with minority stressors (e.g. discrimination, hate-crimes, internalized homonegativity, rejection sensitivity, and microaggressions or everyday indignities) have been consistently linked to adverse mental health outcomes. Elucidating the neural adaptations associated with minority stress exposure will be critical for furthering our understanding of how sexual minorities become disproportionately affected by mental health burdens. UNLABELLED Following PRISMA-guidelines, we systematically reviewed published neuroimaging studies that compared neural dynamics among sexual minority and heterosexual populations, aggregating information pertaining to any measurement of minority stress and relevant clinical phenomena. RESULTS Only 1 of 13 studies eligible for inclusion examined minority stress directly, where all other studies focused on investigating the neurobiological basis of sexual orientation. In our narrative synthesis, we highlight important themes that suggest minority stress exposure may be associated with decreased activation and functional connectivity within the default-mode network (related to the sense-of-self and social cognition), and summarize preliminary evidence related to aberrant neural dynamics within the salience network (involved in threat detection and fear processing) and the central executive network (involved in executive functioning and emotion regulation). Importantly, this parallels neural adaptations commonly observed among individuals with posttraumatic stress disorder (PTSD) in the aftermath of trauma and supports the inclusion of insidious forms of trauma related to minority stress within models of PTSD. CONCLUSIONS Taken together, minority stress may have several shared neuropsychological pathways with PTSD and stress-related disorders. Here, we outline a detailed research agenda that provides an overview of literature linking sexual minority stress to PTSD and insidious trauma, moral affect (including shame and guilt), and mental health risk/resiliency, in addition to racial, ethnic, and gender related minority stress. Finally, we propose a novel minority mosaic framework designed to inform future directions of minority stress neuroimaging research from an intersectional lens.
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Affiliation(s)
- Andrew A Nicholson
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, Canada.,Department of Cognition, Emotion, and Methods in Psychology, University of Vienna, Vienna, Austria.,Department of Medical Biophysics, Western University, London, Canada.,Homewood Research Institute, Guelph, Canada
| | - Magdalena Siegel
- Department of Developmental and Educational Psychology, University of Vienna, Vienna, Austria.,Department of Public Health, Institute of Tropical Medicine Antwerp, Antwerp, Belgium
| | - Jakub Wolf
- Department of Cognition, Emotion, and Methods in Psychology, University of Vienna, Vienna, Austria
| | - Sandhya Narikuzhy
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, Canada
| | - Sophia L Roth
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, Canada
| | - Taylor Hatchard
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, Canada
| | - Ruth A Lanius
- Department of Psychiatry, Western University, London, Canada
| | - Maiko Schneider
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, Canada
| | | | - Margaret C McKinnon
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, Canada.,Homewood Research Institute, Guelph, Canada
| | | | - Patrick Smith
- The Centre of Excellence for PTSD, Royal Ottawa Hospital, Ottawa, Canada
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21
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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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22
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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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23
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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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24
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Shi G, Li X, Zhu Y, Shang R, Sun Y, Guo H, Sui J. The divided brain: Functional brain asymmetry underlying self-construal. Neuroimage 2021; 240:118382. [PMID: 34252524 DOI: 10.1016/j.neuroimage.2021.118382] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 06/26/2021] [Accepted: 07/08/2021] [Indexed: 12/29/2022] Open
Abstract
Self-construal (orientations of independence and interdependence) is a fundamental concept that guides human behaviour, and it is linked to a large number of brain regions. However, understanding the connectivity of these regions and the critical principles underlying these self-functions are lacking. Because brain activity linked to self-related processes are intrinsic, the resting-state method has received substantial attention. Here, we focused on resting-state functional connectivity matrices based on brain asymmetry as indexed by the differential partition of the connectivity located in mirrored positions of the two hemispheres, hemispheric specialization measured using the intra-hemispheric (left or right) connectivity, brain communication via inter-hemispheric interactions, and global connectivity as the sum of the two intra-hemispheric connectivity. Combining machine learning techniques with hypothesis-driven network mapping approaches, we demonstrated that orientations of independence and interdependence were best predicted by the asymmetric matrix compared to brain communication, hemispheric specialization, and global connectivity matrices. The network results revealed that there were distinct asymmetric connections between the default mode network, the salience network and the executive control network which characterise independence and interdependence. These analyses shed light on the importance of brain asymmetry in understanding how complex self-functions are optimally represented in the brain networks.
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Affiliation(s)
- Gen Shi
- School of Computer Science and Technology, Beijing Institute of Technology, Beijing, PR China
| | - Xuesong Li
- School of Computer Science and Technology, Beijing Institute of Technology, Beijing, PR China.
| | - Yifan Zhu
- School of Computer Science and Technology, Beijing Institute of Technology, Beijing, PR China
| | - Ruihong Shang
- School of Computer Science and Technology, Beijing Institute of Technology, Beijing, PR China
| | - Yang Sun
- Center for Biomedical Imaging Research, Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, PR China
| | - Hua Guo
- Center for Biomedical Imaging Research, Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, PR China
| | - Jie Sui
- School of Psychology, University of Aberdeen, Aberdeen, UK.
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25
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Collet S, Bhaduri S, Kiyar M, T’Sjoen G, Mueller S, Guillamon A. Characterization of the 1H-MRS Metabolite Spectra in Transgender Men with Gender Dysphoria and Cisgender People. J Clin Med 2021; 10:2623. [PMID: 34198690 PMCID: PMC8232168 DOI: 10.3390/jcm10122623] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 06/07/2021] [Accepted: 06/10/2021] [Indexed: 11/29/2022] Open
Abstract
Much research has been conducted on sexual differences of the human brain to determine whether and to what extent a brain gender exists. Consequently, a variety of studies using different neuroimaging techniques attempted to identify the existence of a brain phenotype in people with gender dysphoria (GD). However, to date, brain sexual differences at the metabolite level using magnetic resonance spectroscopy (1H-MRS) have not been explored in transgender people. In this study, 28 cisgender men (CM) and 34 cisgender women (CW) and 29 transgender men with GD (TMGD) underwent 1H-MRS at 3 Tesla MRI to characterize common brain metabolites. Specifically, levels of N-acetyl aspartate (NAA), choline (Cho), creatine (Cr), glutamate and glutamine (Glx), and myo-inositol + glycine (mI + Gly) were assessed in two brain regions, the amygdala-anterior hippocampus and the lateral parietal cortex. The results indicated a sex-assigned at birth pattern for Cho/Cr in the amygdala of TMGD. In the parietal cortex, a sex-assigned at birth and an intermediate pattern were found. Though assessed post-hoc, exploration of the age of onset of GD in TMGD demonstrated within-group differences in absolute NAA and relative Cho/Cr levels, suggestive for a possible developmental trend. While brain metabolite levels in TMGD resembled those of CW, some interesting findings, such as modulation of metabolite concentrations by age of onset of GD, warrant future inquiry.
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Affiliation(s)
- Sarah Collet
- Department of Endocrinology, Ghent University Hospital, 9000 Ghent, Belgium
| | - Sourav Bhaduri
- Department of Experimental Clinical and Health Psychology, Ghent University, 9000 Ghent, Belgium; (S.B.); (M.K.); (S.M.)
| | - Meltem Kiyar
- Department of Experimental Clinical and Health Psychology, Ghent University, 9000 Ghent, Belgium; (S.B.); (M.K.); (S.M.)
| | - Guy T’Sjoen
- Department of Endocrinology, Center for Sexology and Gender, Ghent University Hospital, 9000 Ghent, Belgium;
| | - Sven Mueller
- Department of Experimental Clinical and Health Psychology, Ghent University, 9000 Ghent, Belgium; (S.B.); (M.K.); (S.M.)
- Department of Personality, Psychological Assessment and Treatment, University of Deusto, 48007 Bilbao, Spain
| | - Antonio Guillamon
- Departamento de Psicobiología, Facultad de Psicología, Universidad Nacional de Educación a Distancia, 28040 Madrid, Spain;
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26
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Mueller SC, Guillamon A, Zubiaurre-Elorza L, Junque C, Gomez-Gil E, Uribe C, Khorashad BS, Khazai B, Talaei A, Habel U, Votinov M, Derntl B, Lanzenberger R, Seiger R, Kranz GS, Kreukels BPC, Kettenis PTC, Burke SM, Lambalk NB, Veltman DJ, Kennis M, Sánchez FJ, Vilain E, Fisher AD, Mascalchi M, Gavazzi G, Orsolini S, Ristori J, Dannlowski U, Grotegerd D, Konrad C, Schneider MA, T'Sjoen G, Luders E. The Neuroanatomy of Transgender Identity: Mega-Analytic Findings From the ENIGMA Transgender Persons Working Group. J Sex Med 2021; 18:1122-1129. [PMID: 37057468 DOI: 10.1016/j.jsxm.2021.03.079] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 02/22/2021] [Accepted: 03/24/2021] [Indexed: 12/23/2022]
Abstract
BACKGROUND In contrast to cisgender persons, transgender persons identify with a different gender than the one assigned at birth. Although research on the underlying neurobiology of transgender persons has been accumulating over the years, neuroimaging studies in this relatively rare population are often based on very small samples resulting in discrepant findings. AIM To examine the neurobiology of transgender persons in a large sample. METHODS Using a mega-analytic approach, structural MRI data of 803 non-hormonally treated transgender men (TM, n = 214, female assigned at birth with male gender identity), transgender women (TW, n = 172, male assigned at birth with female gender identity), cisgender men (CM, n = 221, male assigned at birth with male gender identity) and cisgender women (CW, n = 196, female assigned at birth with female gender identity) were analyzed. OUTCOMES Structural brain measures, including grey matter volume, cortical surface area, and cortical thickness. RESULTS Transgender persons differed significantly from cisgender persons with respect to (sub)cortical brain volumes and surface area, but not cortical thickness. Contrasting the 4 groups (TM, TW, CM, and CW), we observed a variety of patterns that not only depended on the direction of gender identity (towards male or towards female) but also on the brain measure as well as the brain region examined. CLINICAL TRANSLATION The outcomes of this large-scale study may provide a normative framework that may become useful in clinical studies. STRENGTHS AND LIMITATIONS While this is the largest study of MRI data in transgender persons to date, the analyses conducted were governed (and restricted) by the type of data collected across all participating sites. CONCLUSION Rather than being merely shifted towards either end of the male-female spectrum, transgender persons seem to present with their own unique brain phenotype. Mueller SC, Guillamon A, Zubiaurre-Elorza L, et al. The Neuroanatomy of Transgender Identity: Mega-Analytic Findings From the ENIGMA Transgender Persons Working Group. J Sex Med 2021;18:1122-1129.
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Affiliation(s)
- Sven C Mueller
- Department of Experimental Clinical and Health Psychology, Ghent University, Ghent, Belgium
- Department of Personality, Psychological Assessment and Treatment, University of Deusto, Bilbao, Spain
| | - Antonio Guillamon
- Deparment of Psychobiology, National Distance Education University, Madrid, Spain
| | - Leire Zubiaurre-Elorza
- Department of Methods and Experimental Psychology, Faculty of Psychology and Education, University of Deusto, Bilbao, Spain
| | - Carme Junque
- Faculty of Medicine, University of Barcelona, Barcelona, Spain
| | | | - Carme Uribe
- Faculty of Medicine, University of Barcelona, Barcelona, Spain
| | - Behzad S Khorashad
- Psychiatry and Behavioral Sciences Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- Department of Women's and Children's Health, Karolinska University Hospital, Karolinska Institute, Solna, Stockholm, Sweden
| | - Behnaz Khazai
- Keck School of Medicine, Mark and Mary Stevens Neuroimaging and Informatics Institute, Los Angeles, CA, USA
| | - Ali Talaei
- Psychiatry and Behavioral Sciences Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Ute Habel
- Psychiatry, Psychotherapy, and Psychosomatics, University Clinic RWTH, Aachen, Germany
- Research Centre Jülich, Institute of Neuroscience and Medicine (INM-10), Jülich, Germany
| | - Mikhail Votinov
- Psychiatry, Psychotherapy, and Psychosomatics, University Clinic RWTH, Aachen, Germany
- Research Centre Jülich, Institute of Neuroscience and Medicine (INM-10), Jülich, Germany
| | - Birgit Derntl
- Deptarment of Psychiatry and Psychotherapy, University of Tuebingen, Germany
| | - Rupert Lanzenberger
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
| | - Rene Seiger
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
| | - Georg S Kranz
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
- Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hongkong
| | | | | | - Sarah M Burke
- Psychology, Developmental and Educational Psychology, University of Leiden, Leiden, The Netherlands
| | - Nils B Lambalk
- Obstetrics and Gynaecology, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Dick J Veltman
- Psychiatry, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Mathilde Kennis
- Department of Cognitive Neuroscience, Maastricht University, Maastricht, The Netherlands
| | | | - Eric Vilain
- Center for Genetic Medicine Research, Children's National Hospital, Washington, DC, USA
- Department of Genomics and Precision Medicine, George Washington University, Washington, DC, USA
| | - Alessandra Daphne Fisher
- Andrology, Women's Endocrinology, Gender Incongruence Unit, Careggi University Hospital, Florence, Italy
| | - Mario Mascalchi
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Florence, Italy
| | - Gioele Gavazzi
- Department of Neuroscience, Psychology, Drug Research, Child Health, University of Florence, Florence, Italy
| | - Stefano Orsolini
- Department of Electrical, Electronic, and Information Engineering "Guglielmo Marconi", University of Bologna, Cesena, Italy
| | - Jiska Ristori
- Center for Genetic Medicine Research, Children's National Hospital, Washington, DC, USA
| | - Udo Dannlowski
- Institute for Translational Psychiatry, University of Muenster, Muenster, Germany
| | - Dominik Grotegerd
- Institute for Translational Psychiatry, University of Muenster, Muenster, Germany
| | - Carsten Konrad
- Department of Psychiatry and Psychotherapy, Agaplesion Diakonieklinikum, Rotenburg, Germany
| | | | - Guy T'Sjoen
- Department of Endocrinology & Center for Sexology and Gender, Ghent University Hospital, Ghent, Belgium
| | - Eileen Luders
- School of Psychology, University of Auckland, Auckland, New Zealand
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27
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Predicting outcomes of cross-sex hormone therapy in transgender individuals with gender incongruence based on pre-therapy resting-state brain connectivity. NEUROIMAGE-CLINICAL 2020; 29:102517. [PMID: 33340976 PMCID: PMC7750413 DOI: 10.1016/j.nicl.2020.102517] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 10/06/2020] [Accepted: 11/25/2020] [Indexed: 12/29/2022]
Abstract
Individuals with gender incongruence (GI) experience serious distress due to incongruence between their gender identity and birth-assigned sex. Sociological, cultural, interpersonal, and biological factors are likely contributory, and for some individuals medical treatment such as cross-sex hormone therapy and gender-affirming surgery can be helpful. Cross-sex hormone therapy can be effective for reducing body incongruence, but responses vary, and there is no reliable way to predict therapeutic outcomes. We used clinical and MRI data before cross-sex hormone therapy as features to train a machine learning model to predict individuals' post-therapy body congruence (the degree to which photos of their bodies match their self-identities). Twenty-five trans women and trans men with gender incongruence participated. The model significantly predicted post-therapy body congruence, with the highest predictive features coming from the cingulo-opercular (R2 = 0.41) and fronto-parietal (R2 = 0.30) networks. This study provides evidence that hormone therapy efficacy can be predicted from information collected before therapy, and that patterns of functional brain connectivity may provide insights into body-brain effects of hormones, affecting one's sense of body congruence. Results could help identify the need for personalized therapies in individuals predicted to have low body-self congruence after standard therapy.
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28
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Fernández R, Ramírez K, Gómez-Gil E, Cortés-Cortés J, Mora M, Aranda G, Zayas ED, Esteva I, Almaraz MC, Guillamon A, Pásaro E. Gender-Affirming Hormone Therapy Modifies the CpG Methylation Pattern of the ESR1 Gene Promoter After Six Months of Treatment in Transmen. J Sex Med 2020; 17:1795-1806. [PMID: 32636163 DOI: 10.1016/j.jsxm.2020.05.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 04/25/2020] [Accepted: 05/27/2020] [Indexed: 01/15/2023]
Abstract
BACKGROUND Brain sexual differentiation is a process that results from the effects of sex steroids on the developing brain. Evidence shows that epigenetics plays a main role in the formation of enduring brain sex differences and that the estrogen receptor α (ESR1) is one of the implicated genes. AIM To analyze whether the methylation of region III (RIII) of the ESR1 promoter is involved in the biological basis of gender dysphoria. METHODS We carried out a prospective study of the CpG methylation profile of RIII (-1,188 to -790 bp) of the ESR1 promoter using bisulfite genomic sequencing in a cisgender population (10 men and 10 women) and in a transgender population (10 trans men and 10 trans women), before and after 6 months of gender-affirming hormone treatment. Cisgender and transgender populations were matched by geographical origin, age, and sex. DNAs were treated with bisulfite, amplified, cloned, and sequenced. At least 10 clones per individual from independent polymerase chain reactions were sequenced. The analysis of 671 bisulfite sequences was carried out with the QUMA (QUantification tool for Methylation Analysis) program. OUTCOMES The main outcome of this study was RIII analysis using bisulfite genomic sequencing. RESULTS We found sex differences in RIII methylation profiles in cisgender and transgender populations. Cismen showed a higher methylation degree than ciswomen at CpG sites 297, 306, 509, and at the total fragment (P ≤ .003, P ≤ .026, P ≤ .001, P ≤ .006). Transmen showed a lower methylation level than trans women at sites 306, 372, and at the total fragment (P ≤ .0001, P ≤ .018, P ≤ .0107). Before the hormone treatment, transmen showed the lowest methylation level with respect to cisgender and transgender populations, whereas transwomen reached an intermediate methylation level between both the cisgender groups. After the hormone treatment, transmen showed a statistically significant methylation increase, whereas transwomen showed a non-significant methylation decrease. After the hormone treatment, the RIII methylation differences between transmen and transwomen disappeared, and both transgender groups reached an intermediate methylation level between both the cisgender groups. CLINICAL IMPLICATIONS Clinical implications in the hormonal treatment of trans people. STRENGTHS & LIMITATIONS Increasing the number of regions analyzed in the ESR1 promoter and increasing the number of tissues analyzed would provide a better understanding of the variation in the methylation pattern. CONCLUSIONS Our data showed sex differences in RIII methylation patterns in cisgender and transgender populations before the hormone treatment. Furthermore, before the hormone treatment, transwomen and transmen showed a characteristic methylation profile, different from both the cisgender groups. But the hormonal treatment modified RIII methylation in trans populations, which are now more similar to their gender. Therefore, our results suggest that the methylation of RIII could be involved in gender dysphoria. Fernández R, Ramírez K, Gómez-Gil E, et al. Gender-Affirming Hormone Therapy Modifies the CpG Methylation Pattern of the ESR1 Gene Promoter After Six Months of Treatment in Transmen. J Sex Med 2020;17:1795-1806.
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Affiliation(s)
- Rosa Fernández
- Departamento de Psicología, Centro de Investigaciones Científicas Avanzadas (CICA), Universidade da Coruña (UDC), Campus de Elviña, A Coruña, Spain; Instituto de Investigación Biomédica de A Coruña (INIBIC), CHUAC, SERGAS, A Coruña, Spain.
| | - Karla Ramírez
- Departamento de Psicología, Centro de Investigaciones Científicas Avanzadas (CICA), Universidade da Coruña (UDC), Campus de Elviña, A Coruña, Spain; Instituto de Investigación Biomédica de A Coruña (INIBIC), CHUAC, SERGAS, A Coruña, Spain
| | - Esther Gómez-Gil
- Unidad de Identidad de Género, Instituto de Neurociencias, Hospital Clínic, I.D.I.B.A.P.S., Barcelona, Spain
| | - Joselyn Cortés-Cortés
- Departamento de Psicología, Centro de Investigaciones Científicas Avanzadas (CICA), Universidade da Coruña (UDC), Campus de Elviña, A Coruña, Spain; Instituto de Investigación Biomédica de A Coruña (INIBIC), CHUAC, SERGAS, A Coruña, Spain
| | - Mireia Mora
- Departmento de Endocrinología y Nutrición, Hospital Clínic, Barcelona, Spain
| | - Gloria Aranda
- Departmento de Endocrinología y Nutrición, Hospital Clínic, Barcelona, Spain
| | - Enrique Delgado Zayas
- Departamento de Psicología, Centro de Investigaciones Científicas Avanzadas (CICA), Universidade da Coruña (UDC), Campus de Elviña, A Coruña, Spain; Instituto de Investigación Biomédica de A Coruña (INIBIC), CHUAC, SERGAS, A Coruña, Spain
| | - Isabel Esteva
- Servicio de Endocrinología y Nutrición, Unidad de Identidad de Género del Hospital Regional Universitario de Málaga, Málaga, Spain
| | - Mari Cruz Almaraz
- Servicio de Endocrinología y Nutrición, Unidad de Identidad de Género del Hospital Regional Universitario de Málaga, Málaga, Spain
| | - Antonio Guillamon
- Departamento de Psicobiología, Universidad Nacional de Educación a Distancia, Madrid, Spain
| | - Eduardo Pásaro
- Departamento de Psicología, Centro de Investigaciones Científicas Avanzadas (CICA), Universidade da Coruña (UDC), Campus de Elviña, A Coruña, Spain; Instituto de Investigación Biomédica de A Coruña (INIBIC), CHUAC, SERGAS, A Coruña, Spain
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29
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Uribe C, Junque C, Gómez-Gil E, Abos A, Mueller SC, Guillamon A. Data for functional MRI connectivity in transgender people with gender incongruence and cisgender individuals. Data Brief 2020; 31:105691. [PMID: 32490070 PMCID: PMC7262419 DOI: 10.1016/j.dib.2020.105691] [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: 03/09/2020] [Revised: 04/28/2020] [Accepted: 05/04/2020] [Indexed: 11/23/2022] Open
Abstract
We provide T2*-weighted and T1-weighted images acquired on a 3T MRI scanner obtained from 17 transwomen and 29 transmen with gender incongruence; and 22 ciswomen and 19 cismen that identified themselves to the sex assigned at birth. Data from three different techniques that describe global and regional connectivity differences within functional resting-state networks in transwomen and transmen with early-in-life onset gender incongruence are provided: (1) we obtained spatial maps from data-driven independent component analysis using the melodic tool from FSL software; (2) we provide the functional networks interactions of two functional atlases’ seeds from a seed-to-seed approach; (3) and global graph-theoretical metrics such as the smallworld organization, and the segregation and integration properties of the networks. Interpretations of the present dataset can be found in the original article, doi:10.1016/j.neuroimage.2020.116613[1]. The original and processed nifti images are available in Mendeley datasets. In addition, correlation matrices for the seed-to-seed and graph-theory analyses as well as the graph-theoretical measures were made available in Matlab files. Finally, we present supplementary information for the original article.
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Affiliation(s)
- Carme Uribe
- Medical Psychology Unit, Department of Medicine, Institute of Neuroscience, University of Barcelona, Barcelona
| | - Carme Junque
- Medical Psychology Unit, Department of Medicine, Institute of Neuroscience, University of Barcelona, Barcelona.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED: CB06/05/0018-ISCIII), Barcelona.,Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona
| | | | - Alexandra Abos
- Medical Psychology Unit, Department of Medicine, Institute of Neuroscience, University of Barcelona, Barcelona
| | - Sven C Mueller
- Department of Experimental Clinical and Health Psychology, Ghent University, Ghent, Belgium.,Department of Personality, Psychological Assessment and Treatment, University of Deusto, Bilbao, Spain
| | - Antonio Guillamon
- Departamento de Psicobiologia, Facultad de Psicologia, Universidad Nacional de Educacion a Distancia, Madrid, Spain
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30
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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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Analysis of Four Polymorphisms Located at the Promoter of the Estrogen Receptor Alpha ESR1 Gene in a Population With Gender Incongruence. Sex Med 2020; 8:490-500. [PMID: 32409288 PMCID: PMC7471065 DOI: 10.1016/j.esxm.2020.04.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 03/28/2020] [Accepted: 04/05/2020] [Indexed: 02/06/2023] Open
Abstract
INTRODUCTION Gender incongruence defines a state in which individuals feel discrepancy between the sex assigned at birth and their gender. Some of these people make a social transition from male to female (trans women) or from female to male (trans men). By contrast, the word cisgender describes a person whose gender identity is consistent with their sex assigned at birth. AIM To analyze the implication of the estrogen receptor α gene (ESR1) in the genetic basis of gender incongruence. MAIN OUTCOME MEASURES Polymorphisms rs9478245, rs3138774, rs2234693, rs9340799. METHOD We carried out the analysis of 4 polymorphisms located at the promoter of the ESR1 gene (C1 = rs9478245, C2 = rs3138774, C3 = rs2234693, and C4 = rs9340799) in a population of 273 trans women, 226 trans men, and 537 cis gender controls. For SNP polymorphisms, the allele and genotype frequencies were analyzed by χ2 test. The strength of the SNP associations with gender incongruence was measured by binary logistic regression. For the STR polymorphism, the mean number of repeats were analyzed by the Mann-Whitney U test. Measurement of linkage disequilibrium and haplotype frequencies were also performed. RESULTS The C2 median repeats were shorter in the trans men population. Genotypes S/S and S/L for the C2 polymorphism were overrepresented in the trans men group (P = .012 and P = .003 respectively). We also found overtransmission of the A/A genotype (C4) in the trans men population (P = .017), while the A/G genotype (C4) was subrepresented (P = .009]. The analyzed polymorphisms were in linkage disequilibrium. In the trans men population, the T(C1)-L(C2)-C(C3)-A(C4) haplotype was overrepresented (P = .019) while the T(C1)-L(C2)-C(C3)-G(C4) was subrepresented (P = .005). CONCLUSION The ESR1 is associated with gender incongruence in the trans men population. Fernández R, Delgado-Zayas E,RamírezK, et al. Analysis of Four Polymorphisms Located at the Promoter of the Estrogen Receptor Alpha ESR1 Gene in a Population With Gender Incongruence. Sex Med 2020;8:490-500.
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Peper JS, Burke SM, Wierenga LM. Sex differences and brain development during puberty and adolescence. HANDBOOK OF CLINICAL NEUROLOGY 2020; 175:25-54. [PMID: 33008529 DOI: 10.1016/b978-0-444-64123-6.00003-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Sex differences in behavior, and whether these behavioral differences are related to sex differences in brain development, has been a longstanding topic of debate. Presumably, sex differences can provide critically important leads for explaining the etiology of various illnesses that show (i) large sex differences in prevalence and (ii) have an origin before or during adolescence. The general aim of this chapter is to provide an overview of scientific studies on sex differences in normative brain and behavioral development across puberty and adolescence, including the (sex) hormone-driven transition phase of puberty. Moreover, we describe the literature on brain and behavioral development in gender dysphoria, a severe and persistent incongruence between the self-identified gender and the assigned sex at birth. From the literature it becomes clear there is evidence for a specific link between pubertal maturation and developmental changes in arousal, motivation, and emotion. However, this link is rather similar between boys and girls. Moreover, although there is substantial evidence for sex differences in mean brain structure, these have not always been linked to sex differences in behavior, cognition, or psychopathology. Furthermore, there is little evidence for sex differences in brain development and thus, studies so far have been unable to explain sex differences in cognition. Suggestions for future research and methodologic considerations are provided.
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Affiliation(s)
- Jiska S Peper
- Department of Psychology, Leiden University, Leiden, The Netherlands.
| | - Sarah M Burke
- Department of Psychology, Leiden University, Leiden, The Netherlands
| | - Lara M Wierenga
- Department of Psychology, Leiden University, Leiden, The Netherlands
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