What Is the Diathesis-Stress Model?
The diathesis-stress model is a psychological theory that suggests a direct relationship between diathesis (a person’s predisposition to mental health conditions due to genetics, biology, or difficult life experiences) and stressors (stressful events that happen to people).
How Does the Diathesis-Stress Model Work in Psychology?
The idea behind the diathesis-stress model is that people who have experienced certain life events or have biological/genetic predispositions may be more susceptible to the effects of stressful events. When those stressful events reach a certain threshold, the individual’s vulnerability combines with the stress to increase the likelihood of them developing a mental health condition.
For example, if someone has gone through trauma in the past and is facing pressure in their personal or professional life, they may be more affected by that pressure than someone who hasn’t experienced trauma, and therefore develop anxiety or depression.
For psychologists, the model helps to illustrate that how a person behaves isn’t purely down to nature or nurture. Instead, it reflects a mixture of both, with vulnerability and stress interacting to shape outcomes.
Factors that might predispose someone to lower stress tolerance:
- Genetic factors like family history of mental health conditions, neurochemical imbalances, or temperament traits such as high sensitivity
- Early life experiences such as childhood trauma, loss of a caregiver, unstable home environments, or bullying
- Psychological factors like pre-existing mental health conditions, low self-esteem, perfectionism, or difficulty regulating emotions
- Social and environmental factors such as previous major life stressors, weak support networks, social isolation, or discrimination
These factors don’t always occur in isolation. Quite often, multiple factors layer together to create a stronger predisposition, just as multiple stressors in the workplace can combine to trigger a mental health response.
History and Development of the Model
The term “diathesis” comes from Ancient Greece, where it originally meant “disposition” or “arrangement”. In the 1960s, psychologist Paul Meehl brought the term back into the spotlight when creating what we now know as the “diathesis-stress model”.
Back in the 60s, Meehl was particularly interested in how the model related to schizophrenia; however, his framework ended up gaining wider attention when others in the field recognised how it could help them understand a whole range of complex conditions, including depression, anxiety, and other mood disorders.