Gender diversity is correlated with dimensional neurodivergent traits but not categorical neurodevelopmental diagnoses in children.

BACKGROUND: Gender clinic and single-item questionnaire-based data report increased co-occurrence of gender diversity and neurodevelopmental conditions. The nuances of these associations are under-studied. We used a transdiagnostic approach, combining categorical and dimensional characterization of neurodiversity, to further the understanding of its associations with gender diversity in identity and expression in children. METHODS: Data from 291 children (Autism N = 104, ADHD N = 104, Autism + ADHD N = 17, neurotypical N = 66) aged 4-12 years enrolled in the Province of Ontario Neurodevelopmental Network were analyzed. Gender diversity was measured multi-dimensionally using a well-validated parent-report instrument, the Gender Identity Questionnaire for Children (GIQC). We used gamma regression models to determine the significant correlates of gender diversity among age, puberty, sex-assigned-at-birth, categorical neurodevelopmental diagnoses, and dimensional neurodivergent traits (using the Social Communication Questionnaire and the Strengths and Weaknesses of ADHD Symptoms and Normal Behavior Rating Scales). Internalizing and externalizing problems were included as covariates. RESULTS: Neither a categorical diagnosis of autism nor ADHD significantly correlated with current GIQC-derived scores. Instead, higher early-childhood dimensional autistic social-communication traits correlated with higher current overall gender incongruence (as defined by GIQC-14 score). This correlation was potentially moderated by sex-assigned-at-birth: greater early-childhood autistic social-communication traits were associated with higher current overall gender incongruence in assigned-males-at-birth, but not assigned-females-at-birth. For fine-grained gender diversity domains, greater autistic restricted-repetitive behavior traits were associated with greater diversity in gender identity across sexes-assigned-at-birth; greater autistic social-communication traits were associated with lower stereotypical male expression across sexes-assigned-at-birth. CONCLUSIONS: Dimensional autistic traits, rather than ADHD traits or categorical neurodevelopmental diagnoses, were associated with gender diversity domains across neurodivergent and neurotypical children. The association between early-childhood autistic social-communication traits and overall current gender diversity was most evident in assigned-males-at-birth. Nuanced interrelationships between neurodivergence and gender diversity should be better understood to clarify developmental links and to offer tailored support for neurodivergent and gender-diverse populations.

White matter microstructure in transmasculine and cisgender adolescents: A multiparametric and multivariate study.

Adolescence is a sensitive developmental period for neural sex/gender differentiation. The present study used multiparametric mapping to better characterize adolescent white matter (WM) microstructure. WM microstructure was investigated using diffusion tensor indices (fractional anisotropy; mean, radial, and axial diffusivity [AD]) and quantitative T1 relaxometry (T1) in hormone therapy naïve adolescent cisgender girls, cisgender boys, and transgender boys (i.e., assigned female at birth and diagnosed with gender dysphoria). Diffusion indices were first analyzed for group differences using tract-based spatial statistics, which revealed a group difference in AD. Thus, two multiparametric and multivariate analyses assessed AD in conjunction with T1 relaxation time, and with respect to developmental proxy variables (i.e., age, serum estradiol, pubertal development, sexual attraction) thought to be relevant to adolescent brain development. The multivariate analyses showed a shared pattern between AD and T1 such that higher AD was associated with longer T1, and AD and T1 strongly related to all five developmental variables in cisgender boys (10 significant correlations, r range: 0.21-0.73). There were fewer significant correlations between the brain and developmental variables in cisgender girls (three correlations, r range: -0.54-0.54) and transgender boys (two correlations, r range: -0.59-0.77). Specifically, AD related to direction of sexual attraction (i.e., gynephilia, androphilia) in all groups, and T1 related to estradiol inversely in cisgender boys compared with transgender boys. These brain patterns may be indicative of less myelination and tissue density in cisgender boys, which corroborates other reports of protracted WM development in cisgender boys. Further, these findings highlight the importance of considering developmental trajectory when assessing the subtleties of neural structure associated with variations in sex, gender, and sexual attraction.

Sex-differential patterns of neuropsychological functioning in adults with attention-deficit/hyperactivity disorder.

BACKGROUND: The sex-differential prevalence of attention-deficit/hyperactivity disorder (ADHD) varies across the lifespan, but little is known about sex differences in executive functions in adults with ADHD. METHODS: We assessed 261 adults, aged 18-40 years, diagnosed with ADHD (170 males [assigned at birth], aged 25.81 ± 5.49; 91 females, aged 27.76 ± 5.42) and 308 neurotypical adults (176 males, aged 24.62 ± 5.14; 132 female, aged 25.37 ± 5.42) via psychiatric interviews to confirm ADHD and other psychiatric diagnoses. They were assessed by the Cambridge Neuropsychological Testing Automated Battery (CANTAB) on Reaction Time (arousal/processing speed), Rapid Visual Information Processing (sustained attention), Spatial Span (spatial memory), Spatial Working Memory, Intradimentional/Extradimensional Shift (set-shifting), and Stocking of Cambridge (spatial planning). The primary analyses were adjusted for age, full-scale IQ, and co-occurring psychiatric conditions. RESULTS: Adults with ADHD had various co-occurring psychiatric conditions without sex differences in ADHD-neurotypical differences. Both adult males and females with ADHD performed poorer in all CANTAB tasks than same-sex neurotypical adults. Significant sex-moderating effects were observed in neuropsychological performance, including greater ADHD-neurotypical differences in arousal for females than males and in location memory for spatial tasks in males than females. CONCLUSION: There were no sex-moderating effects in the presence of co-occurring psychiatric conditions in adult ADHD. However, there were sex-moderating effects on how ADHD related to neuropsychological functioning in adulthood. ADHD was associated with more challenges in arousal/processing speed in females and more challenges in strategy use or inhibition in spatial memory in males.

Factors mediating pre-existing autism diagnosis and later suicidal thoughts and behaviors: A follow-up cohort study.

LAY ABSTRACT: Autistic people are more likely to experience suicidal thoughts and behaviors. The underlying relationships between potential risk factors and suicidal thoughts and behaviors in autistic individuals remain unclear. To understand this, we investigated whether specific factors in childhood/youth explain the effects of pre-existing autism spectrum disorder (ASD) diagnoses on later suicidal thoughts and behaviors in adolescence/adulthood. We assessed internalizing and externalizing problems, bullying experiences, and executive functions (including cognitive flexibility, sustained attention, and spatial working memory) at an average baseline age of 13.4 years and suicidal thoughts and behaviors at an average follow-up age of 19.2 years among 129 autistic and 121 typically developing (TD) individuals. During the follow-up period in adolescence/adulthood, autistic individuals were more likely to report suicidal thoughts than TD individuals. Being bullied partially accounted for the relationship between a pre-existing ASD diagnosis and later-reported higher suicidal thoughts. Contrary to our hypothesis, higher (instead of lower) cognitive flexibility in some autistic young people appeared to partially explain their higher rates of suicidal thoughts compared with typically developing young people. The findings imply that school bullying prevention and tailored intervention programs for autistic people, especially those with higher cognitive flexibility, are warranted to reduce their risks of experiencing suicidal thoughts.

Exploring camouflaging by the Chinese version Camouflaging Autistic Traits Questionnaire in Taiwanese autistic and non-autistic adolescents: An initial development.

LAY ABSTRACT: Camouflaging is a coping strategy used by some autistic and other neurodivergent people to fit in neurotypical social contexts. The self-reported Camouflaging Autistic Traits Questionnaire has been validated for use in research with adults in some Western societies, but not in non-Western cultural-ethnic groups. We translated Camouflaging Autistic Traits Questionnaire into traditional Chinese and examined the use of this measure in Taiwanese adolescents via both self-report and caregiver-report in 100 autistic and 105 non-autistic adolescents. Both self-reported and caregiver-reported Chinese version Camouflaging Autistic Traits Questionnaire were composed of two factors (i.e. a "compensation-masking" subscale and an "assimilation" subscale). Both adolescent self-reported and caregiver-reported Chinese version Camouflaging Autistic Traits Questionnaire total score and subscales were reliable in measurement, and they highly correlated with each other. Taiwanese autistic adolescents were more likely to camouflage than non-autistic adolescents, especially on assimilation. Female autistic adolescents showed higher assimilation than male autistic adolescents. Higher camouflaging, especially assimilation, was associated with higher stress in autistic and non-autistic adolescents alike. Both self-reported and caregiver-reported Chinese version Camouflaging Autistic Traits Questionnaire were reliable and offered meaningful information to help us understand the social coping experiences of autistic and non-autistic adolescents.

Short report: Recommendations for education, clinical practice, research, and policy on promoting well-being in autistic youth and adults through a positive focus on sexuality and gender diversity.

LAY ABSTRACT: In this article, we propose recommendations on what we can do to promote that autistic people can enjoy their sexuality and gender identity, because that contributes to overall well-being.First, we briefly summarize the existing research on sexuality and gender diversity in autistic individuals.Next, we propose recommendations for how to promote sexual and gender diversity-related health and well-being. Based on what is known about sexuality, gender diversity, and relationships in autistic adolescents and adults, we convened an international group of autistic and non-autistic researchers, advocates, parents, and professionals to develop recommendations to promote sexual and gender health in autistic people.The resulting recommendations were checked through an online survey distributed to autistic people across the world. The online participants endorsed the importance of eight final recommendations related to:1. Providing education and information on sexuality, relationships, and gender diversity to autistic individuals and their families;2. Improving expertise in and accessibility to healthcare for sexuality, relationships, and gender-related questions, with specific attention to prevention of and support after sexual victimization; and3. Meaningfully including the autism community in future research that addresses well-being relating to sexuality, relationships, and gender diversity.These community-driven recommendations aim to promote sexual health and well-being in autistic individuals internationally.

Dorsal Striatal Functional Connectivity and Repetitive Behavior Dimensions in Children and Youths With Neurodevelopmental Disorders.

BACKGROUND: Impairing repetitive behaviors are one of the core diagnostic symptoms in autism spectrum disorder and obsessive-compulsive disorder, but they also manifest in attention-deficit/hyperactivity disorder. Although the dorsal striatal circuit has been implicated in repetitive behaviors, extensive heterogeneity in and cross-diagnostic manifestations of these behaviors have suggested phenotypic and likely neurobiological heterogeneity across neurodevelopmental disorders (NDDs). METHODS: Intrinsic dorsal striatal functional connectivity was examined in 3 NDDs (autism spectrum disorder, obsessive-compulsive disorder, and attention-deficit/hyperactivity disorder) and typically developing control participants in a large single-cohort sample (N = 412). To learn how diagnostic labels and overlapping behaviors manifest in dorsal striatal functional connectivity measured with functional magnetic resonance imaging, the main and interaction effects of diagnosis and behavior were examined in 8 models (2 seed functional connectivity [caudate and putamen] × 4 sub-behavioral domains [sameness/ritualistic, self-injury, stereotypy, and compulsions]). RESULTS: The obsessive-compulsive disorder group demonstrated distinctive patterns in visual and visuomotor coordination regions compared with the other diagnostic groups. Lower-order repetitive behaviors (self-injury and stereotypy) manifesting across all participants were implicated in regions involved in motor and cognitive control, although the findings did not survive effects of multiple comparisons, suggesting heterogeneity in these behavioral domains. An interaction between self-injurious behavior and an attention-deficit/hyperactivity disorder diagnosis were observed on caudate-cerebellum functional connectivity. CONCLUSIONS: These findings confirmed high heterogeneity and overlapping behavioral manifestations in NDDs and their complex underlying neural mechanisms. A call for diagnosis-free symptom measures that can capture not only observable symptoms and severity across NDDs but also the underlying functions and motivations of such behaviors across diagnoses is needed.

The Toronto Adolescent and Youth Cohort Study: Study Design and Early Data Related to Psychosis Spectrum Symptoms, Functioning, and Suicidality.

BACKGROUND: Psychosis spectrum symptoms (PSSs) occur in a sizable percentage of youth and are associated with poorer cognitive performance, poorer functioning, and suicidality (i.e., suicidal thoughts and behaviors). PSSs may occur more frequently in youths already experiencing another mental illness, but the antecedents are not well known. The Toronto Adolescent and Youth (TAY) Cohort Study aims to characterize developmental trajectories in youths with mental illness and understand associations with PSSs, functioning, and suicidality. METHODS: The TAY Cohort Study is a longitudinal cohort study that aims to assess 1500 youths (age 11-24 years) presenting to tertiary care. In this article, we describe the extensive diagnostic and clinical characterization of psychopathology, substance use, functioning, suicidality, and health service utilization in these youths, with follow-up every 6 months over 5 years, including early baseline data. RESULTS: A total of 417 participants were enrolled between May 4, 2021, and February 2, 2023. Participants met diagnostic criteria for an average of 3.5 psychiatric diagnoses, most frequently anxiety and depressive disorders. Forty-nine percent of participants met a pre-established threshold for PSSs and exhibited higher rates of functional impairment, internalizing and externalizing symptoms, and suicidality than participants without PSSs. CONCLUSIONS: Initial findings from the TAY Cohort Study demonstrate the feasibility of extensive clinical phenotyping in youths who are seeking help for mental health problems. PSS prevalence is much higher than in community-based studies. Our early data support the critical need to better understand longitudinal trajectories of clinical youth cohorts in relation to psychosis risk, functioning, and suicidality.

Neuroimaging and Biosample Collection in the Toronto Adolescent and Youth Cohort Study: Rationale, Methods, and Early Data.

BACKGROUND: The Toronto Adolescent and Youth (TAY) Cohort Study will characterize the neurobiological trajectories of psychosis spectrum symptoms, functioning, and suicidality (i.e., suicidal thoughts and behaviors) in youth seeking mental health care. Here, we present the neuroimaging and biosample component of the protocol. We also present feasibility and quality control metrics for the baseline sample collected thus far. METHODS: The current study includes youths (ages 11-24 years) who were referred to child and youth mental health services within a large tertiary care center in Toronto, Ontario, Canada, with target recruitment of 1500 participants. Participants were offered the opportunity to provide any or all of the following: 1) 1-hour magnetic resonance imaging (MRI) scan (electroencephalography if ineligible for or declined MRI), 2) blood sample for genomic and proteomic data (or saliva if blood collection was declined or not feasible) and urine sample, and 3) heart rate recording to assess respiratory sinus arrhythmia. RESULTS: Of the first 417 participants who consented to participate between May 4, 2021, and February 2, 2023, 412 agreed to participate in the imaging and biosample protocol. Of these, 334 completed imaging, 341 provided a biosample, 338 completed respiratory sinus arrhythmia, and 316 completed all 3. Following quality control, data usability was high (MRI: T1-weighted 99%, diffusion-weighted imaging 99%, arterial spin labeling 90%, resting-state functional MRI 95%, task functional MRI 90%; electroencephalography: 83%; respiratory sinus arrhythmia: 99%). CONCLUSIONS: The high consent rates, good completion rates, and high data usability reported here demonstrate the feasibility of collecting and using brain imaging and biosamples in a large clinical cohort of youths seeking mental health care.

The dimensional structure of the Camouflaging Autistic Traits Questionnaire (CAT-Q) and predictors of camouflaging in a representative general population sample.

OBJECTIVES: Some autistic people "camouflage" their differences by modeling neurotypical behaviors to survive in a neurotypical-dominant social world. It remains elusive whether camouflaging is unique to autism or if it entails similar experiences across human groups as part of ubiquitous impression management (IM). Here we examined camouflaging engagement and theoretical drivers in the general population, drawing on the transactional IM framework and contextualizing findings within both contemporary autism research and the past IM literature. METHODS: A large representative U.S. general population sample (N = 972) completed this survey study. We combined exploratory item factor analysis and graph analysis to triangulate the dimensional structure of the Camouflaging Autistic Traits Questionnaire (CAT-Q) and examined its correspondence with prior autism-enriched psychometric findings. We then employed hierarchical regression and elastic-net regression to identify the predictors of camouflaging, including demographic (e.g., age, gender), neurodivergence (i.e., autistic and ADHD traits), socio-motivational, and cognitive factors. RESULTS: We found a three-factor/dimensional structure of the CAT-Q in the general population, nearly identical to that found in previous autism-enriched samples. Significant socio-motivational predictors of camouflaging included greater social comparison, greater public self-consciousness, greater internalized social stigma, and greater social anxiety. These camouflaging drivers overlap with findings in recent autistic camouflaging studies and prior IM research. CONCLUSIONS: The novel psychometric and socio-motivational evidence demonstrates camouflaging as a shared social coping experience across the general population, including autistic people. This continuity guides a clearer understanding of camouflaging and has key implications for autism scholars, clinicians, and the broader clinical intersecting with social psychology research. Future research areas are mapped to elucidate how camouflaging/IM manifests and functions within person-environment transactions across social-identity and clinical groups.

Brain-charting autism and attention deficit hyperactivity disorder reveals distinct and overlapping neurobiology.

Background: Autism and attention deficit hyperactivity disorder (ADHD) are heterogeneous neurodevelopmental conditions with complex underlying neurobiology. Despite overlapping presentation and sex-biased prevalence, autism and ADHD are rarely studied together, and sex differences are often overlooked. Normative modelling provides a unified framework for studying age-specific and sex-specific divergences in neurodivergent brain development. Methods: Here we use normative modelling and a large, multi-site neuroimaging dataset to characterise cortical anatomy associated with autism and ADHD, benchmarked against models of typical brain development based on a sample of over 75,000 individuals. We also examined sex and age differences, relationship with autistic traits, and explored the co-occurrence of autism and ADHD (autism+ADHD). Results: We observed robust neuroanatomical signatures of both autism and ADHD. Overall, autistic individuals showed greater cortical thickness and volume localised to the superior temporal cortex, whereas individuals with ADHD showed more global effects of cortical thickness increases but lower cortical volume and surface area across much of the cortex. The autism+ADHD group displayed a unique pattern of widespread increases in cortical thickness, and certain decreases in surface area. We also found evidence that sex modulates the neuroanatomy of autism but not ADHD, and an age-by-diagnosis interaction for ADHD only. Conclusions: These results indicate distinct cortical differences in autism and ADHD that are differentially impacted by age, sex, and potentially unique patterns related to their co-occurrence.

Improving autism identification and support for individuals assigned female at birth: clinical suggestions and research priorities.

Emerging evidence suggests that the higher prevalence of autism in individuals who are assigned male than assigned female at birth results from both biological factors and identification biases. Autistic individuals who are assigned female at birth (AFAB) and those who are gender diverse experience health disparities and clinical inequity, including late or missed diagnosis and inadequate support. In this Viewpoint, an international panel of clinicians, scientists, and community members with lived experiences of autism reviewed the challenges in identifying autism in individuals who are AFAB and proposed clinical and research directions to promote the health, development, and wellbeing of autistic AFAB individuals. The recognition challenges stem from the interplay between cognitive differences and nuanced or different presentations of autism in some AFAB individuals; expectancy, gender-related, and autism-related biases held by clinicians; and social determinants. We recommend that professional development for clinicians be supported by health-care systems, professional societies, and governing bodies to improve equitable access to assessment and earlier identification of autism in AFAB individuals. Autistic AFAB individuals should receive tailored support in education, identity development, health care, and social and professional sense of belonging.

Mental health challenges faced by autistic people.

Mental health challenges impede the well-being of autistic people. This Review outlines contributing neurodevelopmental and physical health conditions, rates and developmental trajectories of mental health challenges experienced by autistic people, as well as unique clinical presentations. A framework is proposed to consider four contributing themes to aid personalized formulation: social-contextual determinants, adverse life experiences, autistic cognitive features, and shared genetic and early environmental predispositions. Current evidence-based and clinical-knowledge-informed intervention guidance and ongoing development of support are highlighted for specific mental health areas. Tailored mental health support for autistic people should be neurodivergence-informed, which is fundamentally humanistic and compatible with the prevailing bio-psycho-social frameworks. The personalized formulation should be holistic, considering physical health and transdiagnostic neurodevelopmental factors, intellectual and communication abilities, and contextual-experiential determinants and their interplay with autistic cognition and biology, alongside resilience. Supporting family well-being is integral. Mutual empathic understanding is fundamental to creating societies in which people across neurotypes are all empowered to thrive.

Characterizing Subcortical Structural Heterogeneity in Autism.

Autism presents with significant phenotypic and neuroanatomical heterogeneity, and neuroimaging studies of the thalamus, globus pallidus and striatum in autism have produced inconsistent and contradictory results. These structures are critical mediators of functions known to be atypical in autism, including sensory gating and motor function. We examined both volumetric and fine-grained localized shape differences in autism using a large (n=3145, 1045-1318 after strict quality control), cross-sectional dataset of T1-weighted structural MRI scans from 32 sites, including both males and females (assigned-at-birth). We investigated three potentially important sources of neuroanatomical heterogeneity: sex, age, and intelligence quotient (IQ), using a meta-analytic technique after strict quality control to minimize non-biological sources of variation. We observed no volumetric differences in the thalamus, globus pallidus, or striatum in autism. Rather, we identified a variety of localized shape differences in all three structures. Including age, but not sex or IQ, in the statistical model improved the fit for both the pallidum and striatum, but not for the thalamus. Age-centered shape analysis indicated a variety of age-dependent regional differences. Overall, our findings help confirm that the neurodevelopment of the striatum, globus pallidus and thalamus are atypical in autism, in a subtle location-dependent manner that is not reflected in overall structure volumes, and that is highly non-uniform across the lifespan.

Self-Harm Events and Suicide Deaths Among Autistic Individuals in Ontario, Canada.

Importance: Reasons for elevated suicide risks among autistic people are unclear, with insufficient population-based research on sex-specific patterns to inform tailored prevention and intervention. Objectives: To examine sex-stratified rates of self-harm events and suicide death among autistic individuals compared with nonautistic individuals, as well as the associated sociodemographic and clinical risk factors. Design, Setting, and Participants: This population-based matched-cohort study using linked health administrative databases in Ontario, Canada included all individuals with physician-recorded autism diagnoses from April 1, 1988, to March 31, 2018, each matched on age and sex to 4 nonautistic individuals from the general population. Self-harm events resulting in emergency health care from April 1, 2005, to December 31, 2020, were examined for one cohort, and death by suicide and other causes from April 1, 1993, to December 31, 2018, were examined for another cohort. Statistical analyses were conducted between October 2021 and June 2023. Exposure: Physician-recorded autism diagnoses from 1988 to 2018 from health administrative databases. Main Outcomes and Measures: Autistic and nonautistic individuals who were sex stratified a priori were compared using Andersen-Gill recurrent event models on self-harm events, and cause-specific competing risk models on death by suicide or other causes. Neighborhood-level income and rurality indices, and individual-level broad diagnostic categories of intellectual disabilities, mood and anxiety disorders, schizophrenia spectrum disorders, substance use disorders, and personality disorders were covariates. Results: For self-harm events (cohort, 379 630 individuals; median age at maximum follow-up, 20 years [IQR, 15-28 years]; median age of first autism diagnosis claim for autistic individuals, 9 years [IQR, 4-15 years]; 19 800 autistic females, 56 126 autistic males 79 200 nonautistic females, and 224 504 nonautistic males), among both sexes, autism diagnoses had independent associations with self-harm events (females: relative rate, 1.83; 95% CI, 1.61-2.08; males: relative rate, 1.47; 95% CI, 1.28-1.69) after accounting for income, rurality, intellectual disabilities, and psychiatric diagnoses. For suicide death (cohort, 334 690 individuals; median age at maximum follow-up, 19 years [IQR, 14-27 years]; median age of first autism diagnosis claim for autistic individuals, 10 years [IQR, 5-16 years]; 17 982 autistic females, 48 956 autistic males, 71 928 nonautistic females, 195 824 nonautistic males), there was a significantly higher crude hazard ratio among autistic females (1.98; 95% CI, 1.11-3.56) and a nonsignificantly higher crude hazard ratio among autistic males (1.34; 95% CI, 0.99-1.82); the increased risks were associated with psychiatric diagnoses. Conclusions and Relevance: This cohort study suggests that autistic individuals experienced increased risks of self-harm events and suicide death. Psychiatric diagnoses were significantly associated with the increased risks among both sexes, especially for suicide death, and in partially sex-unique ways. Autism-tailored and autism-informed clinical and social support to reduce suicide risks should consider multifactorial mechanisms, with a particular focus on the prevention and timely treatment of psychiatric illnesses.

Cortical Structure Differences in Relation to Age, Sexual Attractions, and Gender Dysphoria in Adolescents: An Examination of Mean Diffusivity and T1 Relaxation Time.

Recent research found that the combination of masculine gender identity and gynephilia was associated with cortical T1 relaxation time, which is considered to reflect gray matter density. We hypothesized that mean diffusivity (MD), a diffusion tensor imaging metric that reflects the degree to which water movement is free versus constrained, in combination with T1 relaxation time would provide further insight regarding cortical tissue characteristics. MD and T1 relaxation time were measured in 76 cortical regions in 15 adolescents assigned female at birth who experience gender dysphoria (GD AFAB) and were not receiving hormone therapy, 17 cisgender girls, and 14 cisgender boys (ages 12-17 years). Sexual orientation was represented by the degree of androphilia-gynephilia and the strength of sexual attraction. In multivariate analyses, cortical T1 relaxation time showed a weak but statistically significant positive association with MD across the cortex, suggesting that macromolecule-rich cortical tissue also tends to show water movement that is somewhat more constrained. In further multivariate analyses, in several left frontal, parietal, and temporal regions, the combination of shorter T1 relaxation time and faster MD was associated with older age and greater gynephilia in GD AFAB individuals and cisgender boys and with stronger attractions in cisgender boys only. Thus, for these cortical regions in these groups, older age, gynephilia, and stronger attractions (cisgender boys only) were associated with macromolecule-rich tissue in which water movement was freer-a pattern that some prior research suggests is associated with greater cell density and size. Overall, this study indicates that investigating T1 relaxation time and MD together can further inform how cortical gray matter tissue characteristics relate to age and psychosexuality.

The Intersection of Autism and Transgender and Nonbinary Identities: Community and Academic Dialogue on Research and Advocacy.

Many transgender people are autistic. Community expressions of the autism transgender intersection abound. Some commentators have questioned the proportional overrepresentation of autism among gender-diverse people, suggesting these individuals may not be truly autistic or truly transgender. However, increasing evidence challenges assertions that deny the authenticity of co-occurring autistic and transgender identities. Specifically, research by authors of this article indicates autistic transgender people show neurophenotypes generally consistent with cisgender autistic people and implicit gender phenotypes consistent with nonautistic transgender people. This article features a dialogue between eight leading experts in the field of intersectional autism and gender diversity, including clinicians, researchers, community advocates, and experts who are themselves autistic transgender. Key topics of discussion included: how research findings on autism and gender diversity inform respectful and supportive responses to autistic transgender people; the benefits and harms of increased societal attention toward the autism transgender intersection; and research and advocacy priorities. The expert panel concluded the following: (1) it is important to respect transgender autistic people's wellness and resilience, while also acknowledging the pathologization and stigmatization they face; (2) autistic gender-diverse people are experts of their own identity and should be involved in all aspects of research and clinical care; (3) research is needed to understand the disparities autistic transgender people face; (4) attempts to restrict autistic transgender people's access to gender care are unsupported by existing research; (5) adult gender care may benefit from incorporating universal design principles and neurodiversity-affirming strategies to reduce barriers to care and improve clinician-client communication in treatment delivery and the informed consent process; (6) cross-cultural and cross-societal research will improve best care practices in diverse contexts; (7) research and advocacy must be inclusive across ethnoracial identities, including in leadership and perspectives represented; and (8) a life span developmental framework is needed for adult research in this field.

The Gender-Diversity and Autism Questionnaire: A Community-Developed Clinical, Research, and Self-Advocacy Tool for Autistic Transgender and Gender-Diverse Young Adults.

Background: Autistic transgender people face unique risks in society, including inequities in accessing needed care and related mental health disparities. Given the need for specific and culturally responsive accommodations/supports, the characterization of key experiences, challenges, needs, and resilience factors within this population is imperative. This study developed a structured self-report tool for autistic transgender young adults to communicate their experiences and needs in a report format attuned to common autistic thinking and communication styles. Methods: This cross-nation project developed and refined the Gender-Diversity and Autism Questionnaire through an iterative community-based approach using Delphi panel methodology. This proof-of-principle project defined "expertise" broadly, employing a multi-input expert search approach to balance academic-, community-, and lived experience-based expertise. Results: The expert collaborators (N = 24 respondents) completed a two-round Delphi study, which developed 85 mostly closed-ended items based on 90% consensus. Final item content falls within six topic areas: the experience of identities; the impact of experienced or anticipated discrimination, bias, and violence toward autistic people and transgender people; tasks and experiences of everyday life; gender diversity- or autism-related care needs and history; the experience of others doubting an individual's gender identity and/or autism; and the experience of community and connectedness. The majority of retained items relate to tasks and experiences of everyday life or the impact of experienced or anticipated discrimination, bias, and violence. Conclusions: This study employed a multipronged multimodal search approach to maximize equity in representation of the expert measure development team. The resulting instrument, designed for clinical, research, and self-advocacy applications, has parallel Dutch and English versions and is available for immediate use. Future cross-cultural research with this instrument could help identify contextual risk and resilience factors to better understand and address inequities faced by this large intersectional population.

Why is this an important issue?: Transgender and gender-diverse are words used to describe people whose gender varies from their assigned sex at birth. Many autistic people identify as being transgender/gender-diverse. Autistic gender-diverse/transgender young adults often describe difficulties getting the care they need, which can increase their chances of experiencing stress and mental health challenges. This study created a self-report questionnaire for autistic transgender/gender-diverse young adults to share about their health care, support needs, and broader experiences. What were the results of the study?: A diverse group of experts in the autism and gender diversity co-occurrence, including autistic transgender people, worked together to develop the questionnaire. The researchers found experts by searching the internet and talking to people in the community and research field. The questionnaire is called the Gender-Diversity and Autism Questionnaire and has 85 questions that are grouped into 6 different areas: the experience of identities; the impact of experienced or anticipated discrimination, bias, and violence toward autistic people and transgender people; tasks and experiences of everyday life; gender diversity- or autism-related care needs and history; the experience of others doubting an individual's gender identity and/or autism; and the experience of community and connectedness. The questionnaire has English and Dutch versions so it can be used for research in different countries. What do the authors recommend for future research on this topic?: Researchers are currently using the new questionnaire to compare the experiences and needs of autistic transgender young adults in the Netherlands and the United States. The results may help explain why some outcomes are different between autistic transgender young people in the two countries and how culture and society play a role. How will these findings help autistic adults now or in the future?: We created the questionnaire to be used in different settings, including clinics and in research. The questionnaire gives autistic transgender young adults a structured way to communicate their experiences, needs, challenges, and areas of strength. The answers that an autistic transgender young adult gives on the questionnaire could help other people understand the clinical and community supports that the young adult wants and needs. Future studies may use the questionnaire to understand obstacles that autistic transgender young adults may face.

Richer than we thought: neurophysiological methods reveal rich-club network development is frequency- and sex-dependent.

A set of highly connected brain regions called the "rich-club" are vital in integrating information across the functional connectome. Although the literature has identified some changes in rich-club organization with age, little is known about potential sex-specific developmental trajectories, and neurophysiologically relevant frequency-dependent changes have not been established. Here we examine the frequency- and sex-dependent development of rich-club organization using magnetoencephalography in a large normative sample (N = 383) over a wide age span (4-39 years). We report strong divergence between males and females across alpha, beta, and gamma frequencies. While males show increased or no change in rich-club organization with age, females show a consistent, non-linear trajectory that increases through childhood, shifting direction in early adolescence. Using neurophysiological modalities for capturing complex inter-relations between oscillatory dynamics, age, and sex, we establish diverging, sex-specific developmental trajectories of the brain's core functional organization, critically important to our understanding of brain health and disease.