Cocaine polydrug use and its impact on intentional harm recognition: a high-density EEG study

Background: Cocaine and stimulant consumption constitute a significant global issue and are associated with impaired social skills. However, the relationship between substance abuse and intentional harm recognition remains unclear. Intentional harm recognition is a crucial social cognitive ability that allows individuals to determine whether a harmful action performed by another person is deliberate or accidental. Methods: The present study examined self-reported, behavioural, and neural responses associated with intentional harm recognition in n = 19 cocaine polydrug users (COC) and n = 19 healthy controls (HC). High-density electroencephalography (hdEEG) was used to measure brain activity during an Intentional Inference Task (IIT), which assesses fast intention recognition in scenarios involving deliberate or unintentional harm to people and objects. This study took place between 2014 and 2015 in Santiago, Chile. Results: Behaviorally, COC exhibited slower reaction times (RT) than HC. Event-related potential (ERP) analysis revealed late frontal differences in HC when attributing intentional harm, while these differences were absent in COC. Conclusions: These findings suggest a potential shift in COC towards emotional over-involvement and away from rational cognitive assessment of social information. The present results provide new insights into the recognition of intentional harm processing in cocaine polydrug users and highlight the potential clinical benefits of interventions focused on socio-emotional regulation training.