The first aim of the study is to examine the residual effects of cannabis use on the interaction of emotion and higher-order processes required for goal-directed behaviour. The specific focus is the mind’s ability to attend to and manipulate relevant information while autonomously inhibiting subliminal and explicit emotionally laden stimuli. The inhibition action is thought to reflect self-regulation of autonomic processes and is pivotal to preventing distractions in day to day functioning (Uher, Brooks, Bartholdy, Tchanturia, & Campbell, 2014). The study will use a modified version of Uher et al., (2014)’s N-back task that uses a subliminal emotion-laden image prime as interference. Performance in this emotion-cognition paradigm has been linked as a potential trans-diagnostic marker for mental health vulnerability (Schweizer et al., 2019). Therefore, comparisons between cannabis users and non-users will provide insight as to whether certain patterns of cannabis consumption is linked with an increase in mental health vulnerability. The second aim of this study is to examine whether physical activity habits moderates the relationship between the effects of residual cannabis and performance on the emotion-cognition task. The decision to examine physical activity habits in cannabis users is based on clinical and population health studies reporting the beneficial effects of physical activity on the brain (Zschucke, Gaudlitz, & Strohle, 2013), and specifically, to attentional and inhibition processes (Hotting & Roder, 2013). As such, this study will be one of the first to consider how positive lifestyle factors, such as, physical activity, may ‘off-set’ the effects of regular cannabis use on cognition.