1. A method for analyzing an emotional state of a user, in an image display device, the method comprising: outputting, from content, a scene having identification information; receiving information on a user response to the scene; determining an emotional state of the user for the scene on the basis of the information on the user response; storing the determined emotional state in association with the identification information; and outputting additional information on the scene, and/or transmitting the additional information to a mobile terminal, based on the determined emotional state.