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The use of computer-generated (CG) stimuli in face processing research is proliferating due to the ease with which faces can be generated, standardised and manipulated. However there has been surprisingly little research into whether CG faces are processed in the same way as photographs of real faces. The present study assessed how well CG faces tap face identity expertise by investigating whether two indicators of face expertise are reduced for CG faces when compared to face photographs. These indicators were accuracy for identification of own-race faces and the other-race effect (ORE)–the well-established finding that own-race faces are recognised more accurately than other-race faces. In Experiment 1 Caucasian and Asian participants completed a recognition memory task for own- and other-race real and CG faces. Overall accuracy for own-race faces was dramatically reduced for CG compared to real faces and the ORE was significantly and substantially attenuated for CG faces. Experiment 2 investigated perceptual discrimination for own- and other-race real and CG faces with Caucasian and Asian participants. Here again, accuracy for own-race faces was significantly reduced for CG compared to real faces. However the ORE was not affected by format. Together these results signal that CG faces of the type tested here do not fully tap face expertise. Technological advancement may, in the future, produce CG faces that are equivalent to real photographs. Until then caution is advised when interpreting results obtained using CG faces.

Many aspects of faces derived from structural information appear to be neurally represented using norm-based opponent coding. Recently, however, Zhao, Seriès, Hancock, and Bednar (2011) have argued that another aspect with a strong structural component, namely face gender, is instead multichannel coded. Their conclusion was based on finding that face gender aftereffects initially increased but then decreased for adaptors with increasing levels of gender caricaturing. Critically, this interpretation rests on the untested assumption that caricaturing the differences between male and female composite faces increases perceived sexual dimorphism (masculinity/femininity) of faces. We tested this assumption in Study 1 and found that it held for male, but not female faces. A multichannel account cannot, therefore, be ruled out, although a decrease in realism of adaptors was observed that could have contributed to the decrease in aftereffects. However, their aftereffects likely reflect low-level retinotopic adaptation, which was not minimized for most of their participants. In Study 2 we minimized low-level adaptation and found that face gender aftereffects were strongly positively related to the perceived sexual dimorphism of adaptors. We found no decrease for extreme adaptors, despite testing adaptors with higher perceived sexual dimorphism levels than those used by Zhao et al. These results are consistent with opponent coding of higher-level dimensions related to the perception of face gender.

General rightsThis document is made available in accordance with publisher policies. Please cite only the published version using the reference above. Full terms of use are available: http://www.bristol.ac.uk/pure/about/ebr-terms AbstractWe used aftereffects to investigate the coding mechanisms underlying our perception of facial expression. Recent evidence for dimensions that are common to the coding of both expression and identity suggest that the same coding system could be used for both attributes. Identity is adaptively opponent coded by pairs of neural populations tuned to opposite extremes of relevant dimensions. Therefore, we hypothesized that expression would also be opponent coded. An important line of support for opponent coding is that aftereffects increase with adaptor extremity (distance from an average test face) over the full natural range of possible faces. Previous studies have reported that expression aftereffects increase with adaptor extremity. Critically, however, they did not establish the extent of the natural range and so have not ruled out a decrease within that range that could indicate narrowband, multichannel coding. Here we show that expression aftereffects, like identity aftereffects, increase linearly over the full natural range of possible faces and remain high even for impossibly distorted adaptors. These results suggest that facial expression, like face identity, is opponent coded.

Objective Examine the extent to which increasing information integration across displays in a simulated submarine command and control room can reduce operator workload, improve operator situation awareness, and improve team performance. Background In control rooms, the volume and number of sources of information are increasing, with the potential to overwhelm operator cognitive capacity. It is proposed that by distributing information to maximize relevance to each operator role (increasing information integration), it is possible to not only reduce operator workload but also improve situation awareness and team performance. Method Sixteen teams of six novice participants were trained to work together to combine data from multiple sensor displays to build a tactical picture of surrounding contacts at sea. The extent that data from one display were available to operators at other displays was manipulated (information integration) between teams. Team performance was assessed as the accuracy of the generated tactical picture. Results Teams built a more accurate tactical picture, and individual team members had better situation awareness and lower workload, when provided with high compared with low information integration. Conclusion A human-centered design approach to integrating information in command and control settings can result in lower workload, and enhanced situation awareness and team performance. Application The design of modern command and control rooms, in which operators must fuse increasing volumes of complex data from displays, may benefit from higher information integration based on a human-centered design philosophy, and a fundamental understanding of the cognitive work that is carried out by operators.

Face identity can be represented in a multidimensional space centered on the average. It has been argued that the average acts as a perceptual norm, with the norm coded implicitly by balanced activation in pairs of channels that respond to opposite extremes of face dimensions (two-channel model). In Experiment 1 we used face identity aftereffects to distinguish this model from a narrow-band multichannel model with no norm. We show that as adaptors become more extreme, aftereffects initially increase sharply and then plateau. Crucially there is no decrease, ruling out narrow-band multichannel coding, but consistent with a two-channel norm-based model. However, these results leave open the possibility that there may be a third channel, tuned explicitly to the norm (three-channel model). In Experiment 2 we show that alternating adaptation widens the range identified as the average whereas adaptation to the average narrows the range, consistent with the three-channel model. Explicit modeling confirmed the three-channel model as the best fit for the combined data from both experiments. However, a two-channel model with decision criteria allowed to vary between adapting conditions, also provided a very good fit. These results support opponent, norm-based coding of face identity with additional explicit coding of the norm. (PsycINFO Database Record

People are better at recognizing own-race than other-race faces. This other-race effect has been argued to be the result of perceptual expertise, whereby face-specific perceptual mechanisms are tuned through experience. We designed new tasks to determine whether other-race effects extend to categorizing faces by national origin. We began by selecting sets of face stimuli for these tasks that are typical in appearance for each of six nations (three Caucasian, three Asian) according to people from those nations (Study 1). Caucasian and Asian participants then categorized these faces by national origin (Study 2). Own-race faces were categorized more accurately than other-race faces. In contrast, Asian American participants, with more extensive other-race experience than the first Asian group, categorized other-race faces better than own-race faces, demonstrating a reversal of the other-race effect. Therefore, other-race effects extend to the ability to categorize faces by national origin, but only if participants have greater perceptual experience with own-race, than other-race faces. Study 3 ruled out non-perceptual accounts by showing that Caucasian and Asian faces were sorted more accurately by own-race than other-race participants, even in a sorting task without any explicit labelling required. Together, our results demonstrate a new other-race effect in sensitivity to national origin of faces that is linked to perceptual expertise.

How team cognition is conceptualized has evolved rapidly in the last decade with the emerging use of a systems approach, moving the focus from the cognition residing in the heads of individuals, to that distributed across the team. This is referred to as ‘distributed cognition’. Increasingly, network approaches are being explored in attempts to model team distributed cognition. The specific domain of interest in the present study is the sociotechnical system within a maritime control room. This comprises human, machine and software agents interacting to interpret sensor data in order to develop a timely and accurate picture of surrounding contacts at sea. To achieve the goal, information is shared or integrated across the maritime control room consoles. The aim of this study was to develop and apply a suite of workload, situation awareness and team performance measures, including network analysis techniques, to examine how the distributed cognition of a team might change as a function of console configuration and information integration within a control room, and how these changes, if any, impact overall team performance. Sixteen teams of six novices conducted two one-hour scenarios operating generic maritime control room positions. Each team completed a one-hour simulation in each of two console configuration layouts with the order counter-balanced (within-subject design). Half the teams conducted the two scenarios in a high integration condition, and half in a low integration condition (between-subjects). The human machine interface (HMI) designs for the high integration condition emerged from a series of task analyses and user-centered design workshops. The emergent cognitively –oriented HMI designs are based on the assumption that each console can freely share information with other consoles. To create an analogue of current, less-integrated, and more stove-piped systems, a low integration condition was created where not all information was shared across consoles, but instead was shared verbally by console operators. Contacts detected at sea were introduced into the simulation and the team’s task was to assess, report and derive a solution (location, course, and speed) for each detected contact. Individual situation awareness was measured through the Situation Present Assessment Method (SPAM) and individual workload through the Air Traffic Workload Indicator Task (ATWIT). Team interaction from the scenarios were video recorded and we applied the Event Analysis of Systemic Teamwork (EAST) approach to examine the task, social and information networks which emerged. Team performance was measured as the accuracy and timeliness of the solutions We found higher information integration lowered average team workload, and improved average team situation awareness and team performance (faster solutions and a more accurate tactical picture). We found no impact of console configuration on team performance or any other dependent measure. The EAST method uncovered patterns in the network analysis that are potentially explanatory for the team workload, situation awareness and performance findings as a function of the information integration manipulation. This experiment showed that there can be reductions in workload, and improvements to situation awareness and performance when information is shared between consoles in a considered design. This has implications for HMI design within a team setting. The set of diagnostic metrics developed were largely effective in examining teamwork and team performance. Acknowledgements. The authors would like to thank Justin Hill (Royal Australian Navy) for his subject matter expertise, Graeme Muller (elmTEK) for his software, technical and infrastructure support, David Munro-Ford (Total Technology Partners) for his simulation programming, Dr Aaron Roberts for his advice on general aspects of the experiment, and Professor Paul Salmon for his advice on EAST.