Book excerpt: Spoken language communication is arguably the most important activity that distinguishes humans from nonhuman species. While many animal species communicate and exchange information using sound, humans are unique in the complexity of the information that can be conveyed using speech, and in the range of ideas, thoughts and emotions that can be expressed. Despite the importance of speech communication for the entire structure of human society, there are many aspects of this process that are not fully understood. One problem is that research on speech and language is typically carried out by different groups of scientists working on separate aspects of the underlying functional and neural systems. On the one hand, research from an auditory perspective focuses on the acoustical properties of speech sounds, their representation in the auditory system, and how that representation is used to extract phonetic information. On the other hand, research from psycholinguistic perspectives examines the processes by which representations of meaning are extracted from the acoustic-phonetic sequence, and how these are linked to the construction of higher-level linguistic interpretation in terms of sentences and discourse. Till now, there has been relatively little interaction between speech researchers from these two groups, in spite of a dramatic expansion in recent years of research into the neural bases of auditory and linguistic functions. This book bridges the gap between these two lines of research, recognising that both have the same aims in understanding how the motor gestures of a speaker are transformed to sounds and how those are mapped onto meaning in the comprehension of spoken language. It presents the work of leading researchers specializing in a wide range of topics within speech perception and language processing - along with contributions from key researchers in neuroanatomy and neuro-imaging. This important new work cuts through the traditional boundaries and fosters crossdisciplinary interactions in this important and rapidly developing area of the biological and cognitive sciences.