Integrating Inattentional Blindness and Eyewitness Memory

Although there is abundant literature on both inattentional blindness (IB) and eyewitness memory as separate areas of research, there has been little focus on integrating these two. Laney and Loftus (2010) made a strong case for conducting research that combines IB and change blindness (CB) with eyewitness memory. In eyewitness studies that are conducted in laboratory settings, the participants are usually expecting to see something happen and are aware that they will be questioned about the material. In approximately two thirds of eyewitness studies reviewed, researchers showed participants a video, slideshow or series of photos and implied or explicitly told them they would be asked questions about the stimuli. These instructions may have led them to pay closer attention to the events portrayed in the materials than they would have if they had been actual witnesses to the real-life event. This heightened level of expectancy in many of the studies may have resulted in greater frequencies of noticing than would be expected outside of the laboratory where real witnesses are often engaged in some other task or activity when the event occurs. Others (Ihlebaek, Love, Eilertsen, & Magnussen, 2003; Malpass, Sporer, & Koehnken, 1996) have acknowledged these problems with traditional eyewitness studies and Lane (2006) directly addressed effects of concurrent tasks on eyewitness memory. She found that participants who engaged in a secondary task were more susceptible to misinformation presented after viewing a slide show. However, her secondary task was auditory, unrelated to the eyewitness slide sequence, and did not produce inattentional blindness. IB is the failure to notice an unexpected stimulus because attention is focused on another task or object (Mack & Rock, 1998). A few studies have directly addressed how IB and the related phenomenon of CB are relevant in criminal cases. Chabris and Simons (2010) suggested Boston police officer Kenny Conley may have been inattentionally blind to the beating of African-American undercover officer Michael Cox by uniformed officers who mistook Cox for a suspect. Conley, who reportedly ran by within feet of the beating, claimed to have not noticed the assault. Chabris, Weinberger, Fontaine and Simons (2011) simulated this situation in a recent study. They found that 35% of undergraduates following a fellow jogger at night failed to notice three students engaged in a staged fight. Davis, Loftus, Vanous, and Cucciare (2007) conducted a study on CB, which occurs when a change to a visual scene goes undetected. Participants watched a video of a theft in a grocery store. As in typical IB studies, participants were given a task to complete (memorizing items from aisles) while watching the video. Sixty-four percent of participants failed to notice that the person who emerged from behind a display was not the thief who had recently gone behind it, and overall misidentifications were over 70%. The visual attention literature, encompassing both IB and CB, addresses issues pertinent to eyewitness memory performance, such as failure to encode features of a scene or failure to distinguish differences properly. Incorporating aspects of the IB paradigm, like dual task procedures, may result in findings that are more applicable to real-life eyewitness situations where bystanders are not maximally attentive to the important event occurring in front of them. Since Mack and Rock (1998) first coined the term, there have been numerous studies to demonstrate the applicability of IB to various situations. In a well-known study building on Neisser (1979), Simons and Chabris (1999) instructed participants to count basketball passes between team members wearing either white or black shirts in a video. While players passed the ball, a woman in a gorilla costume or a tall woman with an umbrella appeared on screen for 5 seconds, walking through the middle of the screen. Despite the salience of the event, only 54% of participants noticed. …