Reducing Uncertainty in Visual Search through the Priming of Visual-Relatedness and the Manipulation of Observer Expectancy

Abstract

We examined two means of reducing uncertainty in visual search: 1) visual-relatedness of a prime to a target and 2) expectancy (based on the proportion of validly primed trials). The two processes were decoupled using a short and a long inter-stimulus interval to examine their respective time courses in visual search. Twelve participants engaged in a discrimination task and a visual search task. The obtained results suggest that visual-relatedness affects search performance early, but its effects rapidly decay. They also suggest that expectancy requires time to accrue before it can affect visual search performance, but its effects are more long lasting than visual-relatedness. These results offer guidance for designing visual displays. In tasks that require split-second decisions designers should be encouraged to prime visual-relatedness. Moreover if the onset of the display and the required decision are separated by a longer interval, displays should inform users of likely outcomes (i.e. manipulate user's expectations).