It's well known that negative experiences in childhood can increase the risk of developing mental health problems, but that sad fact alone doesn't explain every individual who later develops forms of psychological distress.
In a recent study, researchers sought to explore how peoples' life histories influenced the development of psychopathology – the abnormal thoughts and behaviours that often underpin mental disorders.
As we might expect, the results of the research were mixed: negative childhood experiences can indeed manifest as anxiety or other mental health disorders later in life, but the absence of such experiences is no guarantee you'll be free of the subsequent psychological issues, scientists say.
"This research shows that mental health conditions are not solely determined by early life events," explains evolutionary psychologist Bianca Kahl from the University of South Australia.
"A child who is raised in a happy home, could still grow up to have a mental health disorder."
This may sound like an obvious result, but it's an important piece of research that helps to break down the stigma that mental health issues only happen to some people.
In the study, Kahl and fellow researchers surveyed 343 participants via an online questionnaire, asking them about their family and upbringing, along with several questions probing the nature of their developmental trajectory, mental health, overall wellbeing, and the nature of their relationships and attachments today.
"The study specifically aimed to explore whether life history traits were associated with a general factor of psychopathology or whether they could also predict specific symptom groups," the authors explain in their paper.
In this context, life history traits are a part of what is called life history theory – a framework of analysing how different kinds of life strategies might influence the patterns and experiences people go through over time.
In a very simplified sense, life history strategies can be characterised as fast or slow, with fast often meaning impulsive and present-oriented decision-making and behaviour, in contrast to slow traits, which reflect more deliberative, future-oriented decision-making and behaviour.
What Kahl and her team wanted to analyse was whether fast or slow life strategies were predictive of a general 'p-factor', representing an overall risk or likelihood of developing psychopathology and related mental disorders, which in the past have been found to be linked with fast life history strategies.
"We aimed to answer the research question: how do different symptoms of psychopathology map onto the fast-slow life history continuum?" the researchers write.
"We hypothesised that childhood attachment would moderate the association between early life environment and symptoms of psychopathology, with those who had greater perceived parental support potentially buffered from the effect of childhood environmental harshness, and in-turn reporting fewer symptoms of psychopathology."
In the study, the team found that faster life history traits were associated with general psychopathology, but the results showed some symptoms of psychopathology were in fact associated with slow life history traits.
"Poorer perceived parental support and lower socioeconomic status were associated with higher rates of general psychopathology, for females and males respectively," the team explains.
"These findings are complementary to previous works demonstrating an association between experienced adversity and the p-factor."
Outside of that general association, however, psychopathology symptoms were somewhat split, with the results showing interpersonal sensitivity and depression were more likely for those with a faster life history strategy, whereas somatisation and anxiety were greater for people with a slower life history strategy.
In terms of whether a happy childhood (specifically, perceived parental support) acted as a kind of buffer against psychopathology, the researchers found their hypothesis wasn't supported by the data – suggesting the relationship is more complex, and highlighting a direction for future research, so we can figure out what's really going on here.
"We suspect that it's our expectations about our environments and our ability to adapt to scenarios when our expectations are not being met, that may be influencing our experiences of distress," Kahl says.
"If, as children, we learn how to adapt to change, and we learn how to cope when things do not go our way, we may be in a better position to respond to stress and other risk factors for poor mental health."
The findings are reported in Current Psychology.