Origins of Diversity in Gender Expression and Sexual Orientation

We are currently undertaking several cross-cultural studies to investigate the developmental and evolutionary origins of within-sex variation in gender expression and sexual orientation. This research focuses on numerous demographic, physical, and psychological characteristics thought to be influenced by biological mechanisms that act early in development (i.e., prior to or around the time of birth) or are the result of evolutionary processes contributing to the existence of diversity in gender expression and sexual orientation. Through a cross-cultural approach, it is further possible to identify unique sociocultural factors that influence these traits. In both Canada and Thailand, we examine how these characteristics vary according to gender expression and sexual partner preferences, respectively, to give insight into the developmental and evolutionary processes underpinning these traits. In Thailand, we also consider gender-nonbinary individuals who do not identify as men or women. These include individuals assigned male at birth who take on a feminine social role (i.e., sao praphet song) as well as individuals assigned female at birth who take on a masculine social role (i.e., tom).

This research is supported by the Natural Sciences and Engineering Research Council of Canada, the American Institute of Bisexuality, and the University of Toronto Mississauga.

Children’s Concepts of Gender

Young children often have rigid, stereotyped concepts of what makes a person a boy/man or a girl/woman. As a consequence, when they encounter a peer whose behaviour does not fit these rigid stereotypes (e.g., a boy who prefers to have long vs. short hair; a girl who shows a masculine play style), they are likely to respond with ridicule and rejection. This stream of research seeks to better understand how children think about gender, age-related changes in this thinking, and in particular children’s appraisals of other children whose behavior does not conform to gender stereotypes. A major focus of this research stream also includes investigating how we might best limit children’s negative appraisals and ostracism of other children who do not conform to gender stereotypes.

This research is supported by the Social Sciences and Humanities Research Council of Canada and the University of Toronto Mississauga.

Neuroimaging Studies of Transgender Adolescents and Adults

We are currently conducting two neuroimaging projects using magnetic resonance imaging (MRI).

One project investigates structural and functional brain development among Canadian adolescents who experience gender dysphoria (i.e., distress due to an incongruence between birth-assigned and experienced gender). In addition to investigating unique brain characteristics associated with gender dysphoria, this project longitudinally examines the neurological effects of gender-affirming sex hormone therapies often prescribed to transgender adolescents. These therapies are designed to help align physical secondary sex characteristics with the adolescent’s experienced gender identity, and this research will provide insight regarding possible effects of these therapies on brain maturation.

The second project compares brain structure in a sexually and gender-diverse sample of Thai adults. By comparing brain structure across diverse groups, this research will help to disentangle associations between sex, sexual orientation, and gender identity with the brain, thus allowing us to better discern which brain regions are related to sexual orientation and which are related to gender identity.

The Canadian project is supported by the Canadian Institutes of Health Research, Brain Canada, and the Centre for Addiction and Mental Health. The Thai project is supported by the Natural Sciences and Engineering Research Council of Canada and the American Institute of Bisexuality.

Psychological Well-Being and Gender Expression in Children

A number of clinical studies have indicated that transgender and gender-diverse children experience increased risk of behavioural and emotional challenges such as depression, anxiety, and suicidality. We are currently pursuing studies that investigate childhood gender expression and psychological well-being in community-based Canadian and Thai samples to assess whether this pattern of risk extends to non-clinical populations and across cultures. To the extent that such risk is present, we are also investigating contributing factors, including peer rejection and bullying. Possible protective factors such as parental support are also being considered. This research will help clarify how childhood gender expression is related to mental health needs in the broader population, and will provide insight into strategies for ameliorating behavioural and emotional challenges experienced by transgender and gender-diverse children.

This research is supported by the University of Toronto Mississauga.