Looking for trouble: a description of oculomotor search strategies during live CCTV operation

Abstract

Recent research has begun to address how CCTV operators in the modern control room attempt to search for crime (e.g., Howard et al., 2011). However, an often-neglected element of the CCTV task is that the operators have at their disposal a multiplexed wall of scenes, and a single spot-monitor on which they can select any of these feeds for inspection. Here we examined how 2 trained CCTV operators used these sources of information to search from crime during a morning, afternoon, and night-time shift. We found that they spent surprisingly little time viewing the multiplex wall, instead preferentially spending most of their time searching on the single-scene spot-monitor. Such search must require a sophisticated understanding of the surveilled environment, as the operators must make their selection of which screen to view based on their prediction of where crime is likely to occur. This seems to be reflected in the difference in the screens that they selected to view at different times of the day. For example, night-clubs received close monitoring at night, but were seldom viewed in mid-morning. Such narrowing of search based on a contextual understanding of an environment is not a new idea (e.g., Torralba et al., 2006), and appears to contribute to operator's selection strategy. This research prompts new questions regarding the nature of representation that operators have of their environment, and how they might develop expectation-based search strategies to countermand the demands of the large influx of visual information. Future research should ensure not to neglect examination of operator behavior “in the wild” (Hutchins, 1995a), as such insights are difficult to gain from laboratory based paradigms alone.

Experience in judging intent to harm modulates parahippocampal activity: An fMRI study with experienced CCTV operators

“…This measure was termed the 'salience measure', since we assumed that when the observers were all looking at the same visual point at the same time, this would correspond to a salient event in the clip (e.g. Sawahata et al, 2008;Smith and Mital, 2013;Stainer et al, 2013). After each clip was shown during the eye-tracking experiment, the participant was asked to rate the likelihood that a violent incident occurred after it ended, using a six-point scale that ranged from 1 (extremely unlikely) to 6 (extremely likely).…”

“…However, to be effective, this application of CCTV requires a human operator to be able to identify the presence of hostile intentions from only visual cues in complex scenes (Howard et al, 2011a;Howard et al, 2011b;Howard et al, 2009;Stedmon et al, 2008;Troscianko et al, 2004). The amount of visual information and the number of actions these operators monitor every day is very high, and this makes these individuals optimal subjects for examining how extensive experience in the visual analysis of behavior in real-world scenes affects human brain function.…”

Perception of the visual environment

“…For work and entertainment purposes we view content on screens for much of the time and many of the environments that we find ourselves in during everyday life contain screens. Indeed there are tasks that we perform that rely on screen-based viewing like CCTV surveillance (Stainer, Scott-Brown, & Tatler, 2013). Thus screen-based viewing paradigms can be informative of certain everyday behaviours.…”

CCTV Observation: The Effects of Event Type and Instructions on Fixation Behaviour in an Applied Change Blindness Task

“…less) experienced operator utilising the spot monitor more often. Stainer et al (2013) identified that their observers selectively allocated attention based on expected informativeness. This replicated Howard, Troscianko, and Gilchrist's (2010) finding that participants with more experience watching football matches shifted their eyes to more informative areas of the footage earlier than did non-experienced observers.…”

“…Howard, Troscianko, Gilchrist, Behera, and Hogg (2009) stated that measuring eye movements during CCTV monitoring might produce innovative data to determine the strategies people use when attending to footage. Stainer, Scott-Brown, and Tatler (2013) examined the eye movements of two trained CCTV operators monitoring multiple display screens on a wall, compared to a single-spot monitor (the operator could select only one of multiple screens to inspect in more detail). They found that more attention was allocated to the single-screen-spot monitor than the multiplex display, with the more (cf.…”