Will you precrastinate? Sensitivity to potential performance costs and effort in chronic cannabis users and non-users.

We examined whether those who chronically use cannabis (chronic users), compared to those who do not use cannabis (non-users), tend to precrastinate (start or complete a subgoal as soon as possible) and engage in reactive (vs. proactive) decision-making incurring greater potential costs in task performance and perhaps costs in cognitive and physical effort. Participants walked down a hallway and retrieved two full cups of water (one near and one far from their starting position) in the order of their choice and carried both back to their start location with the goal of not spilling. First-cup choice (near or far) and attributions of first-cup choice were recorded. Counter to expectations, chronic users tended to choose the far cup first (i.e., avoided precrastination), the more efficient choice, and this tendency was not different from non-users. Participants' attributions confirmed that those who chose the far cup first likely engaged in proactive decision-making while those who chose the near cup first likely engaged in reactive decision-making. Additionally, chronic users and non-users utilized proactive control in the AX-Continuous Performance Task even though chronic users had lower short-term and working memory span scores. These results contradict research suggesting chronic users (vs. non-users) are more impulsive, lack inhibitory control, tend to invest physical effort regardless of reward, and tend not to invest cognitive effort for reward. We suggest that chronic cannabis use may not impair decision making as profoundly as previously thought if individuals are motivated by potential consequences of their decisions in tasks with low memory demand.