Biorhythm is an interactive performance, first exhibited at New York University’s Graduate School of Business Administration in 1983. Rapoport worked with a UC Berkeley programmer to adapt a computer program designed to record human biorhythms. In the performance, participants were asked to express with words and a gesture “how they were feeling that evening” to measure their own evaluation of biorhythm condition against a computer-recorded assessment of their emotional/physical state. They sat in a dentist’s chair and donned bibs that provided a contrasting background for their emotion representative gestures that were then photographed. Their spoken words were recorded simultaneously with the photographing of their gestures.