Jean Twenge

Researchers · San Diego State University

The SDSU psychologist who documented the sudden collapse in teen mental health beginning around 2012.

Jean Twenge is a psychologist at San Diego State University who has spent years tracking generational data on teen well-being, documenting a sharp decline in adolescent mental health that began around 2012 — the same period smartphones and social media became a constant presence in young people's lives. Her books "iGen" (2017) and "Generations" (2023) lay out these trends, and her 2025 book "10 Rules for Raising Kids in a High-Tech World" turns the research into practical guidance for parents. She writes the Generation Tech Substack and testified before the Senate Commerce Committee in January 2026 on the association between heavy tech use and adolescent mental health.