The research in this laboratory is concerned with information processing in the realm of human auditory system. In particular, we apply a psychophysical approach to the study of fundamental characteristics of the human auditory spatial perception as well as human multimodal spatial perception including hearing. We are, at the same time, aiming at the realization of a 'comfortable' sound environment exploiting digital signal processing techniques. Three-dimensional auditory displays based on the sound image control by simulating transfer functions of sound paths from sound sources to listeners' external ears, and sensing systems of 3D sound field information are two examples. These systems are expected to provide a high-quality virtual sound space, which is keenly required to realize in the multimedia communication, cyberspace systems and virtual reality systems. Furthermore, in recent years, we have been devoting a lot of effort to the development of advanced digital hearing aids. Our research areas are not restricted to acoustical information sciences, but also cover some other fields like: electronics, mechanical engineering, architecture, medical science, physiology, and psychology, which we feel are the backbones to create the suitable infrastructure for acoustical researches. Interdisciplinary studies are what we stress on in our laboratory.