What term describes the behavior of reverting to an earlier developmental stage due to stress?

The term that describes the behavior of reverting to an earlier developmental stage due to stress is regression. This psychological defense mechanism involves individuals coping with stress by exhibiting behaviors from an earlier period in their life, which may have been less stressful or more comfortable. For example, an adult facing a significant life challenge might start to exhibit childish behaviors, like throwing tantrums or seeking comfort items from their childhood.

Regression can manifest in various ways, such as a child who was previously toilet trained having accidents during a stressful time, or an adult seeking parental comfort during challenging moments. The key aspect of regression is that it serves as a way to escape the pressures of adulthood or current responsibilities by retreating to a time when life seemed simpler.

In contrast, the other terms relate to different psychological responses to stress or conflict: denial involves refusing to accept reality, sublimation channels unacceptable impulses into acceptable behaviors, and displacement transfers feelings from one target to another, often to a safer or more manageable one.