There is increasing evidence for a key role of psychological processes and their central nervous system substrates in functional gastrointestinal disorders, although the exact nature of the relationship remains only partially understood. However, progress in this key area of psychosomatic medicine is rapidly being made. In this review article, we will give an overview of recent advances in understanding the complex mechanisms by which psychological processes and functional gastrointestinal disorder symptoms reciprocally influence each other. Various lines of evidence from different branches of biomedical and psychological science will be discussed, particularly epidemiology, patho- and psychophysiology and functional brain imaging, focusing on the most recent and novel findings. We will conclude this paper with a paragraph on new insights into treatment.