Attention Deficit Hyperactivity Disorder

Inclusion Criteria : * Patients aged over 18 years * For whom a diagnosis of ADHD has been confirmed less than 12 weeks ago * For whom the diagnosis of one or more addictive disorder(s) (substance use disorder or behavioral addiction) has been confirmed * Meeting the indication for treatment with MPH according to European recommendations (Kooij et al., 2019) * For patients who can actually benefit from MPH: who have not yet started taking MPH * Social security affiliates Exclusion Criteria : * Presenting disorders of higher cognitive functions (at the discretion of the referring clinician or the investigator making the inclusion), making data collection impossible * Presenting difficulties in reading or writing the French language making data collection impossible * Unable to commit to being available for the 2 visits planned as part of the cohort * Under guardianship or legal protection * Patients who have used psychoactive substances within 12 hours prior to their visit