The impact of Clonidine, a pharmacological treatment for attention deficit hyperactivity disorder (ADHD), on behavioural and brain imaging measures of attention, inhibition and error processing.

This study is testing how a medication called Clonidine — often used to treat ADHD — affects attention, self-control, and error processing in healthy adult men. Researchers will use brain scans and computer tests to measure these effects, which could help improve our understanding of how Clonidine works in the brain. You may be eligible if: - You are a healthy adult male between 18 and 40 years old - You have normal or corrected-to-normal vision You may NOT be eligible if: - You have a history of any psychiatric illness - You are currently taking any medications - You are a smoker - You use recreational drugs regularly Talk to your doctor about whether this trial might be right for you.