04 Cognitive Psychology: Module 9

Module 9: Attention and Errors Failures of Awareness: The Case of Inattentional Blindness In a groundbreaking series of studies in the 1970s and early 1980s, Neisser and his colleagues devised a visual analogue of the dichotic listening task (Neisser & Becklen, 1975). Their subjects viewed a video of two distinct, but partially transparent and overlapping, events. For example, one event might involve two people playing a hand-clapping game and the other might show people passing a ball. Because the two events were partially transparent and overlapping, both produced sensory signals on the retina regardless of which event received the participant’s attention. When participants were asked to monitor one of the events by counting the number of times the actors performed an action (e.g., hand clapping or completed passes), they often failed to notice unexpected events in the ignored video stream (e.g., the hand-clapping players stopping their game and shaking hands). As with dichotic listening, the participants were unaware of events happening outside the focus of their attention, even when looking right at them. They could tell that other “stuff” was happening on the screen, but many were unaware of the meaning or substance of that stuff.