<p>Impulsivity is a core symptom across multiple addictive disorders, including internet gaming disorder (IGD), yet its multidimensional nature—particularly the neural basis of state and trait impulsivity in IGD—remains poorly understood. We aimed to elucidate the neural correlates of both impulsivity dimensions and uncover how IGD interacts with the heightened impulsive tendencies. Here we conducted a fMRI study with 87 college students at risk for IGD, employing a modified card-guessing task to capture state impulsivity under a loss decision framework. Modified card-guessing paradigm was applied to assess subjects’ state-impulsivity via the loss chasing behavior—the tendency to increase wagers to recover previous losses. Trait impulsivity was assessed using the UPPS-P scale. Another independent cohort (n = 84) with similar IGD profiles was further to validate our finding. Behavioral modelling indicated that state impulsivity, manifesting as the loss chasing behavior (i.e., higher wagers under the loss decision framework), dynamically increased as a function of the loss streaks. Neuroimaging analyses identified key brain regions—such as the right middle frontal gyrus, superior frontal gyrus, striatum, and insula—whose activation during loss feedback predicted subsequent impulsive decisions. These neural signatures of state impulsivity successfully distinguished high-risk IGD individuals. Crucially, resting-state functional connectivity (rs-FC) within these regions not only identified IGD risk but also predicted trait impulsivity. Mediation analysis further demonstrated that IGD’s influence on trait impulsivity was indirectly mediated by rs-FC patterns linked to state impulsivity. Our findings elucidate the distinct yet interconnected neural representations of state and trait impulsivity in IGD, underscoring the neurobehavioral continuum linking transient impulsive states to enduring impulsive traits in IGD.</p>