The impact bias is a cognitive bias where individuals overestimate the intensity and duration of their future emotional responses to events. It reflects the tendency to predict their feelings in the aftermath of both positive and negative experiences inaccurately. While individuals often accurately predict the nature of the emotional response (positive or negative), they struggle to gauge how strong those feelings will be and how long they will last.
In a study by Gilbert et al. (1998), participants predicted their happiness after a job interview. Regardless of whether they received a job offer or not, they predicted feeling significantly worse than they actually did ten minutes later, demonstrating that their initial emotional projections were overly negative.
To overcome impact bias, individuals can try to detach their current emotions from their predictions and consider the full range of future experiences that may influence happiness, recognizing that emotions fluctuate over time and are influenced by multiple factors.