Lawyers for a now-20-year-old woman are arguing that addictive features harmed her mental health in opening statements in a landmark trial against Meta and YouTube, the first of hundreds of similar cases to go to trial.

The plaintiff — identified by her first name, Kaley, or her initials, KGM — and her mother accused the tech companies of intentionally creating addictive platforms that caused her to develop anxiety, body dysmorphia and suicidal thoughts. Lawyers for Meta and YouTube have indicated they will argue that a difficult family life, not social media, was responsible for her mental health challenges.

Speaking on Monday in front of a jury in state court in Los Angeles, Kaley’s lawyer Mark Lanier called social media apps like YouTube and Instagram “digital casinos,” saying the app’s “endless scroll feature” creates dopamine hits that can lead to addiction.