Suspiciousness perception in dynamic scenes: a comparison of CCTV operators and novices
Open Access
- 1 January 2013
- journal article
- Published by Frontiers Media SA in Frontiers in Human Neuroscience
- Vol. 7, 441
- https://doi.org/10.3389/fnhum.2013.00441
Abstract
Perception of scenes has typically been investigated by using static or simplified visual displays. How attention is used to perceive and evaluate dynamic, realistic scenes is more poorly understood, in part due to the problem of comparing eye fixations to moving stimuli across observers. When the task and stimulus is common across observers, consistent fixation location can indicate that that region has high goal-based relevance. Here we investigated these issues when an observer has a specific, and naturalistic, task: closed-circuit television (CCTV) monitoring. We concurrently recorded eye movements and ratings of perceived suspiciousness as different observers watched the same set of clips from real CCTV footage. Trained CCTV operators showed greater consistency in fixation location and greater consistency in suspiciousness judgements than untrained observers. Training appears to increase between-operators consistency by learning “knowing what to look for” in these scenes. We used a novel “Dynamic Area of Focus (DAF)” analysis to show that in CCTV monitoring there is a temporal relationship between eye movements and subsequent manual responses, as we have previously found for a sports video watching task. For trained CCTV operators and for untrained observers, manual responses were most highly related to between-observer eye position spread when a temporal lag was introduced between the fixation and response data. Several hundred milliseconds after between-observer eye positions became most similar, observers tended to push the joystick to indicate perceived suspiciousness. Conversely, several hundred milliseconds after between-observer eye positions became dissimilar, observers tended to rate suspiciousness as low. These data provide further support for this DAF method as an important tool for examining goal-directed fixation behavior when the stimulus is a real moving image.Keywords
This publication has 31 references indexed in Scilit:
- The importance of being expert: Top-down attentional control in visual search with photographsAttention, Perception, & Psychophysics, 2009
- Visual search is guided to categorically-defined targetsVision Research, 2009
- The specificity of the search templateJournal of Vision, 2009
- Head and eye movements and the role of memory limitations in a visual search paradigmJournal of Vision, 2008
- Task-set switching with natural scenes: Measuring the cost of deploying top-down attentionJournal of Vision, 2007
- What do we perceive in a glance of a real-world scene?Journal of Vision, 2007
- Accumulation and persistence of memory for natural scenesJournal of Vision, 2006
- The Time Course of Abstract Visual RepresentationPerception, 2003
- Matching identities of familiar and unfamiliar faces caught on CCTV images.Journal of Experimental Psychology: Applied, 2001
- The Role of Information Reduction in Skill AcquisitionCognitive Psychology, 1996