High load induces inattentional blindness, the phenomenon whereby people fail to notice easily visible stimuli (see Lavie et al., 2014 for a review). Perceptual load does not just affect distraction by irrelevant stimuli it also affects individuals’ subjective awareness of such stimuli. This corresponds with recent evidence that attention becomes more spatially focused under high perceptual load so that peripheral information is not processed to the same extent as central information ( Caparos and Linnell, 2010). Much of this evidence comes from research using variations of the Eriksen flanker task ( Eriksen and Eriksen, 1974) in which interference from a peripheral distractor letter is reduced when the central task-a search array containing other letters-imposes high perceptual load. This theoretical approach builds directly on a large body of research in the field of selective attention, in particular efforts to resolve conflicting accounts of when in the attentional process distracting information is filtered out of awareness (see Murphy et al., 2016 for a review). Load Theory has become a hugely influential model of attention and there is a body of evidence to suggest that high perceptual load reduces behavioral interference by irrelevant distractors (e.g., Lavie, 1995 Lavie and De Fockert, 2003 Forster and Lavie, 2008 but see Khetrapal, 2010 Benoni and Tsal, 2013 Cave and Chen, 2016 for reviews of recent studies challenging the load hypothesis). This can be operationalized by either varying the number of task-related stimuli or by altering the task to be performed on the same stimuli. Perceptual load is defined as “the amount of information involved in the processing of the task stimuli” ( Macdonald and Lavie, 2011, p1780). However, when a task incurs low perceptual load, all available stimuli are processed (including irrelevant distractors) and selective attention takes place at a later stage. Load Theory ( Lavie and Tsal, 1994 Lavie, 1995, 2005) makes specific predictions about the interplay of perception and awareness, stating that as perceptual capacity is limited, when perceptual load is high, irrelevant distractors are less likely to be processed. This includes the ability to recall essential details after witnessing a crime-eyewitness memory. It is what allows us to navigate complex environments and is critical for everyday functioning. Selective attention is what allows us to focus on what is relevant and ignore irrelevant, potentially distracting information. These results have implications for eyewitness memory researchers and forensic professionals. ![]() High visual perceptual load also affected recall for auditory information, illustrating a possible cross-modal perceptual load effect on memory accuracy. High load memories were also more open to suggestion, showing increased susceptibility to leading questions. For example, memory for the central character in the video was not affected by load but memory for a witness who passed by the window at the edge of the scene was significantly worse under high load. The results showed that eyewitnesses were less accurate under high load, in particular for peripheral details. Across three experiments (two video-based and one in a driving simulator), the effect of perceptual load on eyewitness memory was assessed. The current study is the first to assess the effect of perceptual load on eyewitness memory. Given that high load can result in individuals failing to report seeing obvious objects, it is conceivable that load may also impair memory for the scene. ![]() There is evidence that perceptual load affects distractor processing, with increased inattentional blindness under high load. Load Theory ( Lavie, 1995, 2005) states that the level of perceptual load in a task (i.e., the amount of information involved in processing task-relevant stimuli) determines the efficiency of selective attention. 2School of Psychology, University College Dublin, Dublin, Ireland.1School of Applied Psychology, University College Cork, Cork, Ireland.
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