We feel that we are perceiving the world around us as it is, but in fact the perceived world is distorted in various ways, not the same as the physical world. Why do we feel that we can act in our daily life without problems? Recent studies has demonstrated that the majority of behaviors that we felt as consciously performed are actually driven by unconscious processing. My research goal is to clarify the mechanisms of implcit perceptual and cognitive processes by the techniques of experimental psychology. Now we are proceeding research on a wide range of topics, such as attention mechanism to select and discard information, implict learning and memory, role of reward system, formation process of interpersonal impression, unconscious thought, etc.