About the project
There is a lack of knowledge about how mental difficulties and disorders develop during adolescence and into young adulthood. What determines why some individuals develop significant difficulties while others cope well, and how do risk and protective factors affect the development of mental symptoms and disorders? And most importantly, what causal factors underlie the development of mental health problems and resilience?
This project has followed seven national cohorts of twins born in Norway, with data collected at multiple time points to examine this. Twins are essential because they allow for the study of the effects of environmental conditions while controlling for the impact of genetics on those conditions.
When the study began in 2006, the twins were between 12-18 years old. Families who wished to participate completed a comprehensive questionnaire with questions about mental strengths, problems, resources, and life stressors. Both the twins themselves and their parents were invited to respond. After the twins turned 18, they were interviewed about mental symptoms and disorders, traumatic events experienced during their upbringing, as well as strengths and resources within themselves and their surroundings.
Objectives
This research project aims to understand the causal architecture behind differences in adolescent resilience to various life stressors. This knowledge is essential for understanding how humans function when facing challenges in life and for creating better preventive and treatment interventions for those needing help.
Outcomes
The project has published several scientific articles in international journals. While data collection was recently completed, the publishing has been ongoing throughout the project. In addition to research articles, three doctoral degrees and one post-doc scholarship have been awarded due to the project. A doctoral candidate from the project was awarded the King's Gold Medal for the best dissertation in 2023 and the Norwegian Psychological Association's award for the best doctoral thesis in psychology. The project's employees have also contributed to knowledge sharing through interviews and other media appearances.
These are some key findings from the project so far:
• Symptoms of various mental disorders, such as anxiety, depression, eating disorders, and substance abuse, often co-occur (comorbidity) in adolescence. It is mainly shared genetics that influences the co-occurrence of mental symptoms both concurrently and over time, while environmental effects are limited, with primarily local and short-term impacts.
• Adolescents' experience of stressful life events and potentially traumatic events is also largely genetically influenced. The same applies to the burden of experiencing loneliness in adolescence. Our findings mainly show shared genetics as the cause of the association between life events and mental difficulties.
• Resilience is a personality trait, and genetic differences primarily influence differences between individuals in resilience. This is essential knowledge for developing preventive measures based on strengthening this trait.
• Other personal characteristics often considered protective factors, such as the experience of meaning and coherence (sense of coherence), self-efficacy, and life satisfaction, also have significant hereditary components. Our findings contradict theories that these traits are primarily learned or acquired.
Background
The project has been conducted at the Department of Psychology at UiO since 2014, following its initial start and data collection at the Regional Centre for Child and Adolescent Mental Health (RBUP Eastern and Southern Norway).
The project's clinical basis was to provide a better research knowledge base for resilience and coping as factors in preventive mental health work. To do this, the project chose to study the underlying causal mechanisms behind differences in adolescent resilience to various life stressors.
Previous research has demonstrated both concurrent and longitudinal relationships between stressful life events and traumatic experiences and the development of mental symptoms and disorders. Similar relationships have been documented between good mental health and individual personality traits such as resilience, coherence, coping, and self-efficacy. Additionally, studies indicated that such personal resources could function as buffers or protective factors against the development of mental difficulties among individuals who had experienced stressful life events and trauma during adolescence. However, there was a lack of genetically informative studies. Underlying factors could thus cause the observed relationships. That is, to study the effects of environmental factors, it is necessary to control for the effects that genes have on those same factors and relationships.
The chosen method was a classic twin design involving monozygotic (identical) and dizygotic (fraternal) twins raised in the same family. By following these twins over time, one can estimate how much of the similarities and differences in their development are due to genetics and how much is due to the family environment or other unique environmental events for each twin.
Financing
• The Research Council of Norway has funded the project through multiple grants.
• The Department of Psychology has funded a doctoral scholarship and infrastructure.
• The Dam Foundation funds a post-doc position through the Council for Mental Health. See subproject: 'Young and a little bit psychological' - Effective protective factors - Department of Psychology (PSI) (uio.no)
• RBUP Eastern and Southern Norway have contributed support for data collection.
Cooperation
The following researchers are cooperating with the project:
- Nikolai Olavi Czajkowski - Psykologisk institutt (PSI) (uio.no)
- Eivind Ystrøm
- Espen Moen Eilertsen
- Kees-Jan Kan (University of Amsterdam)
- Monika Aldona Waszczuk (Stony Brook University, New York)
- Cristian Kandler (Medical School, Berlin)
- Rainer Riemann (University of Beilefeld)
- Thalia C. Eley (King's College, London)
- René Mõttus (University of Edinburgh)
- Marthe Rump (University of Bremen)
Tools
Data collection was done through Sentio as a data processor.
Data from the project is stored in TSD.