Previous research examining how icons’ concreteness, visual complexity, and distinctiveness influence visual search performance have led to disagreements over which icon characteristic most affects behaviour. These icon characteristics are often poorly defined and interrelated, particularly concreteness. Accordingly, drawing strong inferences about the robustness of concreteness as a factor in search for visual icons is challenging. Here, we operationalised concreteness into three distinct levels: concrete icons were images of real-world objects, photorealistic icons were drawings of the object, and abstract icons were images with no conceptual information. Across two experiments, participants rated each icon on various icon characteristics (e.g. concreteness, visual complexity) to provide a ground truth for these factors and to validate our concreteness manipulation. In a separate study, naive participants performed a visual search task for a target icon. Oculomotor measures were utilised to elucidate how various icon characteristics affected search performance. Although we were unable to fully disassociate concreteness from visual complexity, we found that icons high in concreteness improved search performance, but as visual complexity increased, object identification became slower. This was largely demonstrated through increased verification times for complex targets. The present set of studies indicate that highly concrete and simple icons engender search benefits.

We have developed a measure of transient changes in the useful field of view (UFOV) in simulators using gaze-contingent displays (GCDs). It can be used to evaluate safety-critical tasks such as driving or flight, and in training to increase the UFOV under cognitive load, stress, and fatigue. Unlike the established UFOV© measure, our measure can be used in simulators. Furthermore, previous peripheral detection tasks used in simulators controlled neither the target's retinal eccentricity nor stimulus intensity. Our approach overcomes these limitations by using GCDs to present stimuli producing equal performance across eccentricities under single-task conditions for two dependent measures: blur detection and Gabor orientation discrimination. We then measure attention under dual task conditions by varying cognitive load via an N-back task. Our results showed blur sensitivity varied predictably with retinal eccentricity, but detection of blur did not vary with cognitive load. Conversely, peripheral Gabor orientation discrimination showed a significant cognitive load decrement. While this method is still in development, the results suggest that a GC UFOV method is promising.