A registered report on interruptions during visual search: Examining the effects of perceptual and cognitive load

Interruptions during visual search tasks significantly impair search performance, leading to prolonged reaction time (RT) and reduced accuracy. The interruption's complexity has been proposed as one important factor that might modulate this decline in performance. However, previous research on interruption complexity during visual search has not clearly differentiated between perceptual and cognitive load, making it difficult to evaluate their relative contributions. This preregistered study examines the effects of interruption complexity on visual search performance by independently manipulating perceptual and cognitive load. Participants performed a visual search task interrupted by a running memory span task. During the interruption task, numerical items were either clearly visible (low perceptual load) or masked with Gaussian visual noise (high perceptual load), and participants recalled either the last item (low cognitive load) or the last four items of the list (high cognitive load). We investigated whether perceptual and cognitive effects are additive and whether one factor is more potent than the other. The results advance theoretical knowledge and contribute to a clearer understanding of the underlying mechanisms of interruption-related performance costs.