From fried to focused? A daily diary study of after‐work cannabis use and downstream performance effects

Claims regarding the implications of employee cannabis use vary considerably even though little research explores cannabis as it relates to the modern workplace. Drawing from substance use theories and the epidemiology literature, we develop a conceptual model that suggests after‐work cannabis use is a mechanism to help employees protect cognitive resources in the evening, allowing them to stay engaged at work the next day. In a daily diary study of cannabis users and non‐users, we find no link between after‐work cannabis use and next‐day executive functioning, cognitive engagement or daily task performance. A deeper dive into the literature led to a contextualized model including both within‐ and between‐person moderators that we tested in a second daily diary study of cannabis users. We specifically predict moderated indirect effects from after‐work cannabis use to cognitive engagement at work the following day. Results from this second study indicate after‐work cannabis use interacts with daily workload and a between‐person performance‐related cannabis use motive to predict next‐day cognitive engagement. Daily cognitive engagement is subsequently related to changes in daily task performance. Collectively, results suggest that theories on employee substance use should be updated to better account for the daily effects (or non‐effects) of after‐work cannabis use on important workplace outcomes.