Artificial intelligence (AI) is known for its high energy consumption, especially in data-intensive tasks like health monitoring. To address this, researchers have developed a flexible paper-based sensor composed of nanocellulose and zinc oxide (ZnO) nanoparticles that operates like the human eyes and brain. The sensor is energy-efficient, responds to optical input in real-time, and is both flexible and easy to dispose of, making it ideal for health monitoring applications.