The 2025 study “How AI and Human Behaviors Shape Psychosocial Effects of Extended Chatbot Use,” by researchers at the MIT Media Lab and OpenAI, was a four-week randomized controlled experiment with 981 participants who exchanged more than 300,000 messages with ChatGPT. It measured loneliness, real-world socialization, emotional dependence on the AI, and problematic use, varying both interaction mode and conversation type.