Face masks present a new challenge to face identification (here matching) and emotion recognition in Western cultures. Here, we present the results of three experiments that test the effect of masks, and also the effect of sunglasses (an occlusion that individuals tend to have more experienced with) on (i) familiar face matching, (ii) unfamiliar face matching and (iii) emotion categorization. Occlusion reduced accuracy in all three tasks, with most errors in the mask condition; however, there was little difference in performance for faces in masks compared with faces in sunglasses. Super-recognizers, people who are highly skilled at matching unconcealed faces, were impaired by occlusion, but at the group level, performed with higher accuracy than controls on all tasks. Results inform psychology theory with implications for everyday interactions, security and policing in a mask-wearing society.

Summary: There are large individual differences in the ability to recognise faces. Super-recognisers are exceptionally good at face memory tasks. In London, a small specialist pool of police officers (also labelled 'super-recognisers' by the Metropolitan Police Service) annually makes 1000's of suspect identifications from closed-circuit television footage. Some suspects are disguised, have not been encountered recently or are depicted in poor quality images. Across tests measuring familiar face recognition, unfamiliar face memory and unfamiliar face matching, the accuracy of members of this specialist police pool was approximately equal to a group of non-police super-recognisers. Both groups were more accurate than matched control members of the public. No reliable relationships were found between the face processing tests and object recognition. Within each group, however, there were large performance variations across tests, and this research has implications for the deployment of police worldwide in operations requiring officers with superior face processing ability

The experiments reported in this paper investigated simultaneous identity matching of unfamiliar people physically present in person with moving video images typical of that captured by closed circuit television (CCTV). This simulates the decision faced by a jury in court when the identity of somebody caught on CCTV is disputed. Namely, 'is the defendant in the dock the person depicted in video'? In Experiment 1, the videos depicted medium-range views of a number of actor 'culprits'. Experiment 2 used similar quality images taken a year previously, some of which showed the culprits in disguise. Experiment 3 utilised high-quality close-up video images. It was consistently found that in both culprit-present and culprit-absent videos and in optimal conditions, matching the identity of a person in video can be highly susceptible to error.

Police worldwide regularly review closed-circuit television (CCTV) evidence in investigations. This research found that London police experts who work in a full-time "Super-Recogniser Unit" and front line police identifiers regularly making suspect identifications from CCTV possessed superior unfamiliar face recognition ability and, with higher levels of confidence, outperformed controls at locating actors in a bespoke Spot the Face in a Crowd Test. Police were also less susceptible to change blindness errors and possessed higher levels of conscientiousness and lower levels of neuroticism and openness. Controls who took part in Spot the Face in a Crowd Test actor familiarisation training outperformed untrained controls, suggesting this exercise might enhance identification of persons of interest in real investigations. This research supports an accumulating body of evidence demonstrating that international police forces may benefit from deploying officers with superior face recognition ability to roles such as CCTV review, as these officers may be the most likely to identify persons of interest.

It has been previously demonstrated that extensive activation in the dorsolateral temporal lobes associated with masking a speech target with a speech masker, consistent with the hypothesis that competition for central auditory processes is an important factor in informational masking. Here, masking from speech and two additional maskers derived from the original speech were investigated. One of these is spectrally rotated speech, which is unintelligible and has a similar (inverted) spectrotemporal profile to speech. The authors also controlled for the possibility of "glimpsing" of the target signal during modulated masking sounds by using speech-modulated noise as a masker in a baseline condition. Functional imaging results reveal that masking speech with speech leads to bilateral superior temporal gyrus (STG) activation relative to a speech-in-noise baseline, while masking speech with spectrally rotated speech leads solely to right STG activation relative to the baseline. This result is discussed in terms of hemispheric asymmetries for speech perception, and interpreted as showing that masking effects can arise through two parallel neural systems, in the left and right temporal lobes. This has implications for the competition for resources caused by speech and rotated speech maskers, and may illuminate some of the mechanisms involved in informational masking.

A live showup (known as a street identification in the UK) allows the perpetrator to be identified shortly after a street crime. If the suspect disputes the identification, a video lineup often ensues. Four experiments examined the reliability of live showups and their influence on a subsequent video lineup using realistic procedures and conditions. Similar proportions of culprits and innocent suspects were identified from live showups and video lineups. Both culprits and innocent suspects previously identified were likely to be identified again in a subsequent lineup, with delays from a few minutes to a month. Only a weak effect of clothing bias was observed. There was strong evidence of commitment to a previous identification, but no reliable evidence of source monitoring errors. The results suggest that a live showup is not less fair than a lineup, but use of repeated identification procedures introduces an unfair bias against innocent suspects.Live showups and video lineups 4

Super-recognisers inhabit the extreme high end of an adult face processing ability spectrum in the population. While almost all research in this area has evaluated those with poor or mid-range abilities, evaluating whether super-recognisers' superiority generates distinct electrophysiological brain activity, and transcends to different age group faces (i.e., children's) is important for enhancing theoretical understanding of normal and impaired face processing. It may also be crucial for policing, as super-recognisers may be deployed to operations involving child identification and protection. In Experiment 1, super-recognisers (n = 315) outperformed controls (n = 499) at adult and infant face recognition, while also displaying larger cross-age effects. These findings were replicated in Experiment 2 (super-recognisers, n = 19; controls, n = 28), although one SR with frequent infant exposure showed no cross-age effect. Compared to controls, super-recognisers also generated significantly greater electrophysiological activity in event-related potentials associated with pictorial processing (P1) and explicit recognition (P600). Experiment 3, employing an upright and inverted sequential matching design found super-recognisers (n = 24) outperformed controls (n = 20) at adult and infant face matching, but showed no upright cross-age matching effects. Instead, they displayed larger inversion effects, and cross-age inversion effects, implicating the role of holistic processing in their perceptual superiority. Larger cross-age effects in recognition, but not matching suggests that super-recognisers' adult face recognition is partly driven by experience. However, their enhanced infant face recognition suggest super-recognisers' superiority is also experience-independent, results that have implications for policing and for models of face recognition.

Student participant-witnesses produced 4 composites of unfamiliar faces with a system that uses a genetic algorithm to evolve appearance of artificial faces. Morphs of 4 composites produced by different witnesses (between-witness morphs) were judged better likenesses (Experiment 1) and were more frequently named (Experiment 2) by participants who were familiar with the target actors than were morphs of 4 composites produced by a single witness (within-witness morphs). Within-witness morphs were judged better likenesses and more frequently named than the best or the first-produced individual composites. The same results for likeness judgments were observed after possible artifacts in the comparison of between- and within-witness morphs were eliminated (Experiment 3). Experiment 4 showed that both internal and external features were better represented in morphs than in the original composites, although the representation of internal features improved more. The results suggest that morphing improves the representation of faces by reducing random error. Between-witness morphs yield more benefit than within-witness morphs by reducing consistent but idiosyncratic errors of individual witnesses. The experiments provide the first demonstration of an advantage for within-witness morphs produced using a single system. Experiment 2 provides the first demonstration of a reliable advantage for between-witness morphs in the most forensically relevant task: naming a composite of a familiar person produced by a witness who was unfamiliar with the target. Morphing would enhance the recognition of facial composites of criminals. Within-witness morphing provides a methodology for use in crimes in which the victim is the only witness.