Delay discounting, the tendency to prefer immediate rewards over larger delayed rewards, is associated with various health-risk behaviours, such as substance use and psychological disorders. It is therefore important to investigate interventions specifically targeting this tendency. One such intervention is Episodic Future Thinking (EFT). This is a brief intervention that encourages individuals to vividly imagine personally meaningful and positive future events occurring at specific timepoints. Although EFT has shown promise in earlier research, its effectiveness may depend on individual differences. One factor that may influence how individuals make decisions about the future is perceived stress. Stress has been linked to increased delay discounting and may interfere with the cognitive mechanisms underlying EFT. This study therefore examined whether 1) EFT can effectively reduce delay discounting and 2) if perceived stress moderates this effect. It was expected that individuals with less perceived stress will show a greater change in delay discounting following EFT. 

Using an experimental design, frequent cannabis users were randomly assigned to either an EFT intervention or a control condition. Changes in delay discounting were measured before and after the intervention, and perceived stress levels were assessed as a potential moderator. 

The results show that EFT did not significantly reduce delay discounting compared to the control condition, and perceived stress did not influence this relationship. Instead, individuals’ baseline tendency to discount delayed rewards was the strongest predictor in post-intervention delay discounting. Additional exploratory analysis showed that reward type had a significant effect in delay discounting as cannabis rewards were discounted more steeply than monetary rewards. These findings suggest that in frequent cannabis users EFT does not significantly reduce delay discounting and perceived stress at baseline does not moderate this effect. The limitations and implications will be discussed.