Three-Year r/ChatGPT Study Reveals AI's Emotional Impact Surge After GPT-4o

A comprehensive new study analyzing three years of posts on the r/ChatGPT subreddit provides a data-driven look at how AI chatbots have integrated into society. Conducted by researchers including Jessica Dai, Sean Garcia, Emma Pierson, Benjamin Recht, and Nika Haghtalab from UC Berkeley and Cornell, the paper introduces PuLSE (Public and Longitudinal Signals for Evaluation) – a framework for monitoring societal impact trends in real time. By examining posts from the subreddit's creation on December 1, 2022, through the present, the team found that ChatGPT has largely become normalized as an everyday consumer product. However, a significant shift occurred after the launch of GPT-4o in May 2024: posts discussing using ChatGPT for mental health support and posts about developing emotional attachments to the chatbot rose steadily in frequency. The authors note that PuLSE could detect this increased emotional engagement as early as October 2024 – months before OpenAI publicly acknowledged such impacts.

The study's findings have important implications for how we understand the societal effects of widely adopted AI. The PuLSE framework is designed to be a proactive monitoring tool, capable of identifying emerging trends that might otherwise go unnoticed until they reach a critical mass. The researchers created an interactive website that updates daily with live data, allowing ongoing observation of these trends. The paper, accepted at ICML 2026, represents one of the first longitudinal analyses of online discourse around a specific AI product. For technologists and policymakers, it highlights the need for continuous, real-time monitoring of public sentiment and usage patterns, especially as AI systems become more capable and emotionally engaging. The rise in emotional attachment posts after GPT-4o suggests that as AI gains more natural interaction capabilities, users may form deeper bonds – raising both opportunities for mental health support and risks around over-reliance.