The aim of this series is to present a survey of recent research in the fields of speech, hearing and language processing as carried out in various international laboratories. In the past these fields have been rather isolated from each other, but currently they appear to be drawing closer together. It is hoped this series will encourage this trend. The inaugural volume featured chapters on speech signal processing, automatic recognition, synthesis, perception and speech aids for the handicapped. This second volume of the series discusses a wide variety of research into speech, hearing and language processing. This reflects the numerous techniques which have been developed to explore these interrelated subjects.