Abstract Physiological computing involves the direct interfacing of human physiology and computer technology, i.e. brain–computer interaction (BCI). The goal of physiological computing is to transform bioelectrical signals from the human nervous system into real-time computer input in order to enhance and enrich the interactive experience. Physiological computing has tremendous potential for interactive innovation but research activities are often disparate and uneven, and fail to reflect the multidisciplinary nature of the topic. This paper will provide a primer on detectable human physiology as an input source, a summary of relevant research and a research agenda to aid the future development of interactive systems that utilise physiological information.