So are we completely a product of our environment or is this stuff all just preset by genetics? This age-old “nature versus nurture” argument still gets hashed out in many places. But research from the past 30 years has consistently observed the relatively equal and interacting influence of nature and nurture in most cases.
The popular diathesis-stress model provides a nice illustration. This model asserts that we all have some degree of genetic propensity or psychological risk (“diathesis”) to any mental health condition. The degree of stress we may experience from our environment influences the chance of activating that risk and developing a certain condition.
So an individual may have a strong genetic risk for developing schizophrenia. Low to moderately stressful life event(s) may then activate that risk. Or they may have a low genetic risk to develop bipolar disorder. A high to extreme level of life stress could still activate that risk and the individual could experience symptoms.
Nature and nurture also often interact or “transact” to influence our experiences. Temperament is our genetic tendency toward certain types and degrees of emotional reactions. Babies’ temperment can interact with responses from caregivers to influence their development. For instance, a pleasant baby often yields pleasant responses from parents. Those parent-child interactions likely continue to be pleasant through development. That child is more likely to grow up in a relatively low-stress environment.
On the other hand, a colicky baby is often more difficult for parents to find ways to soothe. These parents often experience and express higher levels of distress from this difficulty. Chances increase for that child to grow up in a higher-stress environment. This risk also places the child at higher risk of psychological difficulties.
Linehan’s biosocial model of borderline personality development also fits this pattern. She posits that high emotional sensitivity in children (nature/genetics) can interact with dismissive or highly critical parenting styles. This transaction contributes to high risk for developing borderline personality disorder.
This interaction of nature and nurture gives us an informative window into the experiences of our clients. There are things that none of us can control (e.g., genetic make-up, the state of caregiving we were born into). But this research shows that a large proportion of our experience is within our ability to influence. We can help clients find ways to influence their own environments and life situations to exert agency and improve their mental health.
