Closing the loop: Modelling action, perception and information

Visual interfaces to computer systems are interactive. The cycle of visual interaction involves both visual perception and action. This paper examines formal models of interactive systems and cognitive models of users. Neither completely captures the special nature of visual interaction. In order to investigate this, the paper examines two forms of non-visual interaction: mathematics for the blind and interaction by smell (nasal interaction). Finally three forms of more pragmatic design-oriented method are considered: information rich task analysis (what information is required), status-event analysis (when it is perceived) and models of information (how to visually interact with it).