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The repeated viewing of a suspect’s face by an eyewitness during the commission of a crime and subsequently when presented with
suspects in a photo lineup provides a real-world scenario where Noton and Stark’s 1971 “scanpath theory” of visual perception and memory can be tested. Noton and Stark defined “scanpaths” as repetitive sequences of fixations and saccades that occur during exposure and subsequently upon re-exposure to a visual stimulus, facilitating recognition. Ten subjects watched a video of a staged theft in a parking lot. Scanpaths were recorded for the initial viewing of the suspect’s face and a later close-up viewing of the suspect’s face in the video, and then on the suspect’s face when his picture appeared 24 hours later in a photo lineup constructed by law enforcement officers. These scanpaths were compared using the string-edit methodology to measure resemblance between sequences. Preliminary analysis showed support for repeated scanpath sub-sequences. In the analysis of four clusters of scanpaths, there was little within-subject resemblance between full scanpath sequences but seven of 10 subjects had repeated scanpath sub-sequences. When a subject’s multiple scanpaths across the suspect’s photo in the lineup were compared, instances of within-subjects repetition of short scanpaths occurred more often than expected due to chance.