Doctors prescribe medicines like Adderall and Ritalin to treat conditions like attention deficit hyperactivity disorder (ADHD). Sometimes, people who don't have these conditions take other people's medicines because they think they'll help them focus while doing schoolwork. These drugs are stimulants. They can increase alertness, energy, heart rate, breathing rate, and blood pressure for a short time. Study drugs don't actually increase learning or thinking ability, though. If you suddenly stop using this medication, you may have withdrawal symptoms such as depression, suicidal thoughts, or other mental/mood changes Though it helps many people, this medication may sometimes cause addiction. AHDH drugs works by increasing the amount of dopamine released in the striatum, a key region in the brain related to motivation, action and cognition higher levels of dopamine make both humans and rodents more motivated to perform physically demanding tasks.

https://kidshealth.org/en/teens/study-drugs.html#:~:text=What%20Are%20Study%20Drugs%3F,them%20focus%20while%20doing%20schoolwork.

https://www.radboudumc.nl/en/news/2020/ritalin-enhances-your-ability-to-do-tasks-by-making-you-more-motivated