In a new study, University of Cambridge researchers found that recalling positive events and experiences can help young people build resilience against depression in later life.
Moreover, a known risk factor of depression is exposure to early life stress, such as illness, parents’ separation or death, or adverse family circumstances.
“Mental health disorders that first occur in adolescence are more severe and more likely to recur in later life,” said Dr. Anne-Laura van Harmelen, the study’s senior author.
“With child and adult mental health services underfunded and overstretched, it is critical that we identify new ways to build resilience, particularly in those adolescents who are most at risk for depression.”
Reminiscing about past events is something people often do, according to researchers — sometimes as a strategy for lifting mood. Given this knowledge, a team of researchers from the University of Cambridge and University College London set out to examine whether remembering positive experiences could protect against stress when it occurs in adolescence.
To test their hypothesis, the researchers analyzed data from 427 young people, average age of 14 years, all of whom were considered to be at risk of depression. To test the hypothesis that recalling positive memories is beneficial to teens’ mental health, researchers assessed two signs of vulnerability to depression: negative self-related thoughts and high morning levels of the stress hormone cortisol.
At the start of the experiment, all participants took part in a ‘cued recall Autobiographical Memory Test’. This involved giving the participants a word, either positive or negative, and asking them to recall a specific memory related to the word.
Previous studies have shown that people who are depressed find it difficult to recall specific memories, relying instead on more general recollections.
In a semi-structured interview, the participants reported on the frequency of moderate to severe negative life events in the past 12 months. In addition, they self-reported any symptoms of depression during the previous two weeks and negative self-related thoughts.
The interviews were then repeated 12 months later. The researchers also took saliva samples across four days at both the start of the study and after a year to examine levels of morning cortisol.
The team found that recalling specific positive memories was associated with fewer negative self-related thoughts and with lower levels of cortisol 12 months later. In other words, remembering more specific positive events reduced their vulnerability to depression over the course of one year.
Further investigation showed that recalling positive events only reduced negative self-related thoughts and depressive symptoms in response to stressful life events, but not if the adolescents had experienced no stressful life events.
“Our work suggests that ‘remembering the good times’ may help build resilience to stress and reduce vulnerability to depression in young people,” said Cambridge graduate student Adrian Dahl Askelund, the study’s lead author.