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Recent research has examined the extent to which face and voice processing are associated by virtue of the fact that both tap into a common person perception system. However, existing findings do not yet fully clarify the role of familiarity in this association. Given this, two experiments are presented that examine face-voice correlations for unfamiliar stimuli (Experiment 1) and for familiar stimuli (Experiment 2). With care being taken to use tasks that avoid floor and ceiling effects and that use realistic speech-based voice clips, the results suggested a significant positive but small-sized correlation between face and voice processing when recognizing unfamiliar individuals. In contrast, the correlation when matching familiar individuals was significant and positive, but much larger. The results supported the existing literature suggesting that face and voice processing are aligned as constituents of an overarching person perception system. However, the difference in magnitude of their association here reinforced the view that familiar and unfamiliar stimuli are processed in different ways. This likely reflects the importance of a pre-existing mental representation and cross-talk within the neural architectures when processing familiar faces and voices, and yet the reliance on more superficial stimulus-based and modality-specific analysis when processing unfamiliar faces and voices.

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Vocal identity processing depends on the ability to tell apart two instances of different speakers whilst also being able to tell together two instances of the same speaker. Whilst previous research has examined these voice processing capabilities under relatively common listening conditions, it has not yet tested the limits of these capabilities. Here, two studies are presented that employ challenging listening tasks to determine just how good we are at these voice processing tasks. In Experiment 1, 54 university students were asked to distinguish between very similar sounding, yet different speakers (celebrity targets and their impersonators). Participants completed a 'Same/Different' task and a 'Which is the Celebrity?' task to pairs of speakers, and a 'Real or Not?' task to individual speakers. In Experiment 2, a separate group of 40 university students was asked to pair very different sounding instances of the same speakers (speaking and singing). Participants were presented with an array of voice clips and completed a 'Pairs Task' as a variant of the more traditional voice sorting task. The results of Experiment 1 suggested that significantly more mistakes were made when distinguishing celebrity targets from their impersonators than when distinguishing the same targets from control voices. Nevertheless, listeners were significantly better than chance in all three tasks despite the challenge. Similarly, the results of Experiment 2 suggested that it was significantly more difficult to pair singing and speaking clips than to pair two speaking clips, particularly when the speakers were unfamiliar. Again, however, the performance was significantly above zero, and was again better than chance in a cautious comparison. Taken together, the results suggest that vocal identity processing is a highly adaptable task, assisted by familiarity with the speaker. However, the fact that performance remained above chance in all tasks suggests that we had not reached the limit of our listeners' capability, despite the considerable listening challenges introduced. We conclude that voice processing is far better than previous research might have presumed.

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The present article reports on one experiment designed to examine the importance of familiarity when processing vocal identity. A voice sorting task was used with participants who were either personally familiar or unfamiliar with three speakers. The results suggested that familiarity supported both an ability to tell different instances of the same voice together, and to tell similar instances of different voices apart. In addition, the results suggested differences between the three speakers in terms of the extent to which they were confusable, underlining the importance of vocal characteristics and stimulus selection within behavioural tasks. The results are discussed with reference to existing debates regarding the nature of stored representations as familiarity develops, and the difficulty when processing voices over faces more generally.

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Two experiments are presented, which explore the presence of a distinctiveness advantage when recognising unfamiliar voices. In Experiment 1, distinctive voices were recognised significantly better, and with greater confidence, in a sequential same/different matching task compared with typical voices. These effects were replicated and extended in Experiment 2, as distinctive voices were recognised better even under challenging listening conditions imposed by nonsense sentences and temporal reversal. Taken together, the results aligned well with similar results when processing faces, and provided a useful point of comparison between voice and face processing.

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Thirty years on from their initial observation that familiar voice recognition is not the same as unfamiliar voice discrimination (van Lancker and Kreiman, 1987), the current paper reviews available evidence in support of a distinction between familiar and unfamiliar voice processing. Here, an extensive review of the literature is provided, drawing on evidence from four domains of interest: the neuropsychological study of healthy individuals, neuropsychological investigation of brain-damaged individuals, the exploration of voice recognition deficits in less commonly studied clinical conditions, and finally empirical data from healthy individuals. All evidence is assessed in terms of its contribution to the question of interest - is familiar voice processing distinct from unfamiliar voice processing. In this regard, the evidence provides compelling support for van Lancker and Kreiman's early observation. Two considerations result: First, the limits of research based on one or other type of voice stimulus are more clearly appreciated. Second, given the demonstration of a distinction between unfamiliar and familiar voice processing, a new wave of research is encouraged which examines the transition involved as a voice is learned.

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The data accessible here represents the training tool used with novice students prior to an assessment of their performance in a fingerprint matching task (Stevenage and Pitfield, 2016; Stevenage and Bennett, in preparation) [1,2]. The training tool was compiled following semi-structured interviews with practicing fingerprint experts within the UK (Stevenage and Pitfield, 2016) [1], and has been verified as being a useful summary document by a subset of these experts. Also provided are the performance data of trained student participants on a fingerprint matching task. This was undertaken under biased and unbiased contextual conditions, and under control conditions in which no contextual information was provided. These resources are provided here to enable the interested reader to extend analysis in this area through studying the performance of non-naïve participants, and to complete a meta-analysis across relevant studies.

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One study is presented which explores the biasing effects of irrelevant contextual information on a fingerprint matching task. Bias was introduced by providing the outcomes of a DNA test relating to each fictitious case under consideration. This was engineered to suggest either a match, no match, or an inconclusive outcome, and was thus either consistent, misleading or unbiased depending on the ground truth of each fingerprint pair. The results suggested that, when the difficulty of the fingerprint matching task was measurably increased, participants became more vulnerable to the biasing information. Under such conditions, when performance was good, misleading evidence lowered accuracy, and when performance was weaker, consistent evidence improved accuracy. As such, the results confirmed existing demonstrations of cognitive bias from contextual information in the fingerprint task. Moreover, by taking a process-based approach, it became possible to articulate the concerns, and the potential solutions, at each stage of the workflow. The results offer value for the forensic science community in extending the evidence-base regarding cognitive bias, and in articulating routes to improve the credibility of fingerprint decisions.

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Understanding the relationship between physiological measurements from human subjects and their demographic data is important within both the biometric and forensic domains. In this paper we explore the relationship between measurements of the human hand and a range of demographic features. We assess the ability of linear regression and machine learning classifiers to predict demographics from hand features, thereby providing evidence on both the strength of relationship and the key features underpinning this relationship. Our results show that we are able to predict sex, height, weight and foot size accurately within various data-range bin sizes, with machine learning classification algorithms out-performing linear regression in most situations. In addition, we identify the features used to provide these relationships applicable across multiple applications.

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The data described here provide standard performance measures following administration of a fingerprint matching task to expert analysts, trained students and novice control participants. Measures include accuracy on 'same' and 'different' trials, and the associated measures of sensitivity of discrimination (d') and response bias (C). In addition, speed of correct response is provided. The provision of these data will enable the interested reader to conduct meta-analyses relating to questions of fingerprint expertise and fingerprint training (see "Fact or friction: examination of the transparency, reliability and sufficiency of the ACE-V method of fingerprint analysis" (Stevenage and Pitfield, in press) [1]).

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Three studies are presented which provide a mixed methods exploration of fingerprint analysis. Using a qualitative approach (Expt 1), expert analysts used a 'think aloud' task to describe their process of analysis. Thematic analysis indicated consistency of practice, and experts' comments underpinned the development of a training tool for subsequent use. Following this, a quantitative approach (Expt 2) assessed expert reliability on a fingerprint matching task. The results suggested that performance was high and often at ceiling, regardless of the length of experience held by the expert. As a final test, the experts' fingerprint analysis method was taught to a set of naïve students, and their performance on the fingerprint matching task was compared both to the expert group and to an untrained novice group (Expt 3). Results confirmed that the trained students performed significantly better than the untrained students. However, performance remained substantially below that of the experts. Several explanations are explored to account for the performance gap between experts and trained novices, and their implications are discussed in terms of the future of fingerprint evidence in court.

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Two experiments are presented to explore the limits when matching a sample to a suspect utilising the hand as a novel biometric. The results of Experiment 1 revealed that novice participants were able to match hands at above-chance levels as viewpoint changed. Notably, a moderate change in viewpoint had no notable effect, but a more substantial change in viewpoint affected performance significantly. Importantly, the impact of viewpoint when matching hands was smaller than that when matching ears in a control condition. This was consistent with the suggestion that the flexibility of the hand may have minimised the negative impact of a sub-optimal view. The results of Experiment 2 confirmed that training via a 10-min expert video was sufficient to reduce the impact of viewpoint in the most difficult case but not to remove it entirely. The implications of these results were discussed in terms of the theoretical importance of function when considering the canonical view and in terms of the applied value of the hand as a reliable biometric across viewing conditions.

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Recent literature has raised the suggestion that voice recognition runs in parallel to face recognition. As a result, a prediction can be made that voices should prime faces and faces should prime voices. A traditional associative priming paradigm was used in two studies to explore within-modality priming and cross-modality priming. In the within-modality condition where both prime and target were faces, analysis indicated the expected associative priming effect: The familiarity decision to the second target celebrity was made more quickly if preceded by a semantically related prime celebrity, than if preceded by an unrelated prime celebrity. In the cross-modality condition, where a voice prime preceded a face target, analysis indicated no associative priming when a 3-s stimulus onset asynchrony (SOA) was used. However, when a relatively longer SOA was used, providing time for robust recognition of the prime, significant cross-modality priming emerged. These data are explored within the context of a unified account of face and voice recognition, which recognizes weaker voice processing than face processing.

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The results of two experiments are presented in which participants engaged in a face-recognition or a voice-recognition task. The stimuli were face-voice pairs in which the face and voice were co-presented and were either "matched" (same person), "related" (two highly associated people), or "mismatched" (two unrelated people). Analysis in both experiments confirmed that accuracy and confidence in face recognition was consistently high regardless of the identity of the accompanying voice. However accuracy of voice recognition was increasingly affected as the relationship between voice and accompanying face declined. Moreover, when considering self-reported confidence in voice recognition, confidence remained high for correct responses despite the proportion of these responses declining across conditions. These results converged with existing evidence indicating the vulnerability of voice recognition as a relatively weak signaller of identity, and results are discussed in the context of a person-recognition framework.

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Soft biometrics are a new form of biometric identification which use physical or behavioral traits that can be naturally described by humans. Unlike other biometric approaches, this allows identification based solely on verbal descriptions, bridging the semantic gap between biometrics and human description. To permit soft biometric identification the description must be accurate, yet conventional human descriptions comprising of absolute labels and estimations are often unreliable. A novel method of obtaining human descriptions will be introduced which utilizes comparative categorical labels to describe differences between subjects. This innovative approach has been shown to address many problems associated with absolute categorical labels-most critically, the descriptions contain more objective information and have increased discriminatory capabilities. Relative measurements of the subjects' traits can be inferred from comparative human descriptions using the Elo rating system. The resulting soft biometric signatures have been demonstrated to be robust and allow accurate recognition of subjects. Relative measurements can also be obtained from other forms of human representation. This is demonstrated using a support vector machine to determine relative measurements from gait biometric signatures-allowing retrieval of subjects from video footage by using human comparisons, bridging the semantic gap.

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The results of two experiments are presented which explore the effect of distractor items on face and voice recognition. Following from the suggestion that voice processing is relatively weak compared to face processing, it was anticipated that voice recognition would be more affected by the presentation of distractor items between study and test compared to face recognition. Using a sequential matching task with a fixed interval between study and test that either incorporated distractor items or did not, the results supported our prediction. Face recognition remained strong irrespective of the number of distractor items between study and test. In contrast, voice recognition was significantly impaired by the presence of distractor items regardless of their number (Experiment 1). This pattern remained whether distractor items were highly similar to the targets or not (Experiment 2). These results offer support for the proposal that voice processing is a relatively vulnerable method of identification.

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The results of three experiments explore the role of familiarity in face processing. Using the complete-over-part advantage (Experiment 1) and the chimeric faces task (Experiment 2), the results revealed evidence for what may be termed "holistic processing" of unfamiliar, newly learned, and famous faces. Notably, the extent of holistic processing on both tasks was not moderated by the familiarity of the stimuli. Experiment 3 replicated this pattern using a simultaneous chimeric task to rule out a simple explanation through memory demands. Taken together, these three experiments provide robust and convergent evidence to suggest that all faces regardless of familiarity can be processed in a holistic fashion. On the basis of these results, discussion is presented regarding the value of considering different "types" of facial processing over and above a more simple consideration of task difficulty.

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Two experiments are reported which examine the degree to which conversational recall is affected by facial disfigurement. In Experiment 1, participants viewed a video interview and then immediately recalled the information given by the speaker. Recall fell from 68 per cent to 52 per cent when a fake disfigurement was visible on the speaker's face. In Experiment 2, these results were replicated in a more realistic simulated webcam interaction. Again, immediate conversational recall fell substantially from 85 per cent to 51 per cent when the speaker had a fake disfigurement. In both experiments, however, overt reactions through personality ratings were unaffected by appearance. Reasons for such reactions are discussed, together with the value to the individual in knowing and expecting such reactions.

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Within the word recognition literature, word-frequency and hence familiarity has been shown to affect the degree of repetition priming. The current paper reports two experiments which examine whether familiarity also affects the degree of repetition priming for faces. The results of Experiment 1 confirmed that familiarity did moderate the degree of priming in a face recognition task. Low familiarity faces were primed to a significantly greater degree than high familiarity faces in terms of accuracy, speed, and efficiency of processing. Experiment 2 replicated these results but additionally, demonstrated that familiarity moderates priming for name recognition as well as face recognition. These results can be accommodated within both a structural account of repetition priming (Burton, Bruce & Johnston, 1990) and an Episodic Memory account of repetition priming (see Roediger, 1990), and are discussed in terms of a common mechanism for priming, learning and the representation of familiarity.

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Recent work has demonstrated that facial familiarity can moderate the influence of inversion when completing a configural processing task. Here, we examine whether familiarity interacts with intermediate angles of orientation in the same way that it interacts with inversion. Participants were asked to make a gender classification to familiar and unfamiliar faces shown at seven angles of orientation. Speed and accuracy of performance were assessed for stimuli presented (i) as whole faces and (ii) as internal features. When presented as whole faces, the task was easy, as revealed by ceiling levels of accuracy and no effect of familiarity or angle of rotation on response times. However, when stimuli were presented as internal features, an influence of facial familiarity was evident. Unfamiliar faces showed no increase in difficulty across angle of rotation, whereas familiar faces showed a marked increase in difficulty across angle, which was explained by significant linear and cubic trends in the data. Results were interpreted in terms of the benefit gained from a mental representation when face processing was impaired by stimulus rotation.

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The nominal competitor effect suggests that, when a person has two names associated with them, recall of either name is more difficult than if they just had one name. Drawing on a connectionist framework, this effect could arise either if multiple names were represented as being connected to a single person identity node (PIN), or if multiple names were represented as being connected via one-to-one links to multiple PINs. Whilst the latter has intuitive appeal, results from two experiments support the former architecture. Having two names connected to a single PIN not only gives rise to a nominal competitor effect (Experiment 1), but also gives rise to a familiarity enhancement effect (Experiment 2). These empirical results are simulated using an extension of Brédart, Valentine, Calder, and Gassi's (1995) connectionist architecture, which reveals that both effects hold even when the association of both names to the PIN is unequal. These results are presented in terms of a more complete model for person recognition, and the representation of semantic information within such a model is examined.

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