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Change detection of objects and events in our visual surroundings is sometimes severely difficult, especially if these changes are unexpected. Such failures in change detection may cause huge malicious outcomes in contexts characterized by high levels of complexity and risk. For operators within organizations active in such contexts, effective change detection is a necessary step for functional feedback control in the pursuit of achieving specified goals. This thesis demonstrates examples of change detection failures from aviation, defence, healthcare, and road traffic.

The purpose of the thesis is to present a support concept for enhanced change detection in complex and high risk contexts. The design requirements are primarily provided by the field of command and control. The main mechanisms behind the problems of change detection are identified as the psychological phenomena of change blindness and inattentional blindness. A theoretical foundation is presented regarding these phenomena, complemented with a review concerning orientation and capture of visual attention. The solution space for enhanced change detection is explored and a gap in the literature is identified; there is a need for a support concept which considers both blindness phenomena simultaneously. The thesis elaborates on a conceptual design; an adaptive attention aware system (A3S), based on cuing of visual attention.

The thesis includes four experimental studies. The first examines the effects of instruction on change detection performance. The remaining studies evaluate the possibilities to orient visual attention by a non-obtrusive flash cue in a radar-like display, to compensate for inadequate expectations in a situation characterized by high levels of uncertainty. The participants’ performance is measured in accuracy (hit frequencies) and response times.

The results indicate that; (a) instructions can affect change detection performance, (b) the bottom-up flash cue enhance change detection independent of perceptual load, (c) the flash cue enhance change detection in both static and dynamic environments, and (d) the flash cue is beneficial for change detection even when its position is outside foveal vision in relation to the changed target object. Design propositions for an A3S are presented, derived from the results of the thesis.