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Research investigating the effect of lighting and viewpoint changes on unfamiliar and newly learnt faces has revealed that such recognition is highly image dependent and that changes in either of these leads to poor recognition accuracy. Three experiments are reported to extend these findings by examining the effect of apparent age on the recognition of newly learnt faces. Experiment 1 investigated the ability to generalize to novel ages of a face after learning a single image. It was found that recognition was best for the learnt image with performance falling the greater the dissimilarity between the study and test images. Experiments 2 and 3 examined whether learning two images aids subsequent recognition of a novel image. The results indicated that interpolation between two studied images (Experiment 2) provided some additional benefit over learning a single view, but that this did not extend to extrapolation (Experiment 3). The results from all studies suggest that recognition was driven primarily by pictorial codes and that the recognition of faces learnt from a limited number of sources operates on stored images of faces as opposed to more abstract, structural, representations.

People are more likely to unconsciously plagiarise ideas from a same-sex partner than a different-sex partner, and more likely to unconsciously plagiarise if recalling alone rather than in the presence of their partner [Macrae, C. N., Bodenhausen, G. V., & Calvini, G. (1999). Contexts of cryptomnesia: May the source be with you. Social Cognition, 17, 273-297. doi: 10.1521/soco.1999.17.3.273 ]. Two sets of experiments explore these phenomena, using extensions of the standard unconscious plagiarism paradigm. In Experiment 1A participants worked together in same- or different-sex dyads before trying to recall their own ideas or their partner's ideas. More source errors were evident for same-sex dyads (Experiment 1A), but this effect was absent when participants recalled from both sources simultaneously (Experiment 1B). In Experiment 2A, participants recalled ideas from a single source either alone or in the presence of the partner, using an extended-recall task. Partner presence did not affect the availability of ideas, but did reduce the propensity to report them as task compliant, relative to a partner-present condition. Simultaneous recall from both sources removed this social effect (Experiment 2B). Thus social influences on unconscious plagiarism are apparent, but are influenced by the salience of the alternate source at retrieval.

Background: Guidelines of the International Consensus on the Diabetic Foot state that "Amputation of the lower extremity or part of it is usually preceded by a foot ulcer". The authors' impression has been that this statement might not be applicable among patients treated in our institution. A prospective cohort study was designed to determine the frequency distribution of antecedents of lower limb infection or gangrene and amputation among adult diabetics admitted to a Regional Hospital in western Jamaica., Methods: Adult diabetics admitted to Hospital with a primary diagnosis of lower limb infection and/or gangrene were eligible for recruitment for a target sample size of 126. Thirty five variables were assessed for each patient-episode of infection and/or gangrene, main outcome variable being amputation during admission or 6-months follow-up. Primary statistical output is the frequency distribution of antecedents/precipitants of lower limb infection and/or gangrene. The data is interrogated by univariate and multivariable logistic regression for variables statistically associated with the main antecedent/precipitant events., Results: Data for 128 patient-episodes were recorded. Most common antecedents/precipitants, in order of decreasing frequency, were idiopathic acute soft tissue infection/ulceration (30.5%, CI; 22.6-39.2%), chronic neuropathic ulcer (23.4%, CI; 16.4-31.7%), closed puncture wounds (19.5%, CI; 13.1-27.5%) and critical limb ischemia (7.8%, CI; 3.8-13.9%). Variables positively associated with non-traumatic antecedents/precipitants at the 5% level of significance were male gender and non-ulcerative foot deformity for idiopathic acute soft tissue infection/ulcer; diabetes >5 years, previous infection either limb, insulin dependence and peripheral sensory neuropathy for chronic neuropathic ulcer and older age, diabetes >5 years, hypertension, non-palpable distal pulses and ankle-brachial index ≤0.4 for critical limb ischemia., Conclusions: Chronic neuropathic ulcer accounted for only 23.4 % of lower limb infections and 27.7% of amputations in this population of diabetics, making it the second most common antecedent of either after acute idiopathic soft tissue infection/ulcer at 30.5 and 34.7% respectively. Trauma as a group (defined as closed puncture wounds, lacerations, contusion/blunt trauma and burns) also accounted for a greater number of lower limb infections but fewer amputations than chronic neuropathic ulcer, at 32 and 19.5% respectively.

For familiar faces, the internal features (eyes, nose, and mouth) are known to be differentially salient for recognition compared to external features such as hairstyle. Two experiments are reported that investigate how this internal feature advantage accrues as a face becomes familiar. In Experiment 1, we tested the contribution of internal and external features to the ability to generalize from a single studied photograph to different views of the same face. A recognition advantage for the internal features over the external features was found after a change of viewpoint, whereas there was no internal feature advantage when the same image was used at study and test. In Experiment 2, we removed the most salient external feature (hairstyle) from studied photographs and looked at how this affected generalization to a novel viewpoint. Removing the hair from images of the face assisted generalization to novel viewpoints, and this was especially the case when photographs showing more than one viewpoint were studied. The results suggest that the internal features play an important role in the generalization between different images of an individual's face by enabling the viewer to detect the common identity-diagnostic elements across non-identical instances of the face.

Congenital prosopagnosia is a condition that, present from an early age, makes it difficult for an individual to recognise someone from his or her face. Typically, research into prosopagnosia has employed static images that do not contain the extra information we can obtain from moving faces and, as a result, very little is known about the role of facial motion for identity processing in prosopagnosia. Two experiments comparing the performance of four congenital prosopagnosics with that of age matched and younger controls on their ability to learn and recognise (Experiment 1) and match (Experiment 2) novel faces are reported. It was found that younger controls' recognition memory performance increased with dynamic presentation, however only one of the four prosopagnosics showed any improvement. Motion aided matching performance of age matched controls and all prosopagnosics. In addition, the face inversion effect, an effect that tends to be reduced in prosopagnosia, emerged when prosopagnosics matched moving faces. The results suggest that facial motion can be used as a cue to identity, but that this may be a complex and difficult cue to retain. As prosopagnosics performance improved with the dynamic presentation of faces it would appear that prosopagnosics can use motion as a cue to recognition, and the different patterns for the face inversion effect that occurred in the prosopagnosics for static and dynamic faces suggests that the mechanisms used for dynamic facial motion recognition are dissociable from static mechanisms., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

It is sometimes argued that the implementation of an overall similarity classification is less effortful than the implementation of a single-dimension classification. In the current article, we argue that the evidence securely in support of this view is limited, and report additional evidence in support of the opposite proposition--overall similarity classification is more effortful than single-dimension classification. Using a match-to-standards procedure, Experiments 1A, 1B and 2 demonstrate that concurrent load reduces the prevalence of overall similarity classification, and that this effect is robust to changes in the concurrent load task employed, the level of time pressure experienced, and the short-term memory requirements of the classification task. Experiment 3 demonstrates that participants who produced overall similarity classifications from the outset have larger working memory capacities than those who produced single-dimension classifications initially, and Experiment 4 demonstrates that instructions to respond meticulously increase the prevalence of overall similarity classification.

Face perception remains one of the most intensively researched areas in psychology and allied disciplines, and there has been much debate regarding the early origins and experiential determinants of face processing. This article reviews studies, the majority of which have appeared in the past decade, that discuss possible mechanisms underlying face perception at birth and document the prominent role of experience in shaping infants' face-processing abilities. In the first months of life, infants develop a preference for female and own-race faces and become better able to recognize and categorize own-race and own-species faces. This perceptual narrowing and shaping of the "face space" forms a foundation for later face expertise in childhood and adulthood and testifies to the remarkable plasticity of the developing visual system.

The processes of overall similarity sorting were investigated in 5 free classification experiments. Experiments 1 and 2 demonstrated that increasing time pressure can reduce the likelihood of overall similarity categorization. Experiment 3 showed that a concurrent load also reduced overall similarity sorting. These findings suggest that overall similarity sorting can be a time-consuming analytic process. Such results appear contrary to the idea that overall similarity is a nonanalytic process (e.g., T. B. Ward, 1983) but are in line with F. N. Milton and A. J. Wills's (2004) dimensional summation hypothesis and with the stochastic sampling assumptions of the extended generalized context model (K. Lamberts, 2000). Experiments 4 and 5 demonstrated that the relationship between stimulus presentation time and overall similarity sorting is nonmonotonic, and the shape of the function is consistent with the idea that the three aforementioned processes operate over different parts of the time course.

Previous studies examining face learning have mostly used only a single exposure to 1 image of each of the faces to be learned. However, in daily life, faces are usually learned from multiple encounters. These 6 experiments examined the effects on face learning of repeated exposures to single or multiple images of a face. All experiments provided evidence for image-specific picture learning taking place over and above any invariant face learning, with recognition accuracy always highest for the image studied and performance falling across transformations between study and test images. The relative roles of pictorial and structural codes in mediating learning faces from photographs need to be reconsidered.

Several studies have shown that participants, without a deficit in face recognition, give an increased skin conductance response (SCR) to familiar faces when presented subliminally, hence suggesting covert recognition of these faces. In the experiment presented here we manipulated familiarity and attractiveness and tested whether participants distinguished between faces for these variables when presented too fast to allow conscious recognition. Three sets of faces were presented: famous attractive; unfamiliar attractive; and unfamiliar less attractive. SCRs were the same for each category of faces whether presented subliminally or supraliminally, and were the same for attractive faces, whether famous or unfamiliar; however, SCRs differed between the attractive and less attractive faces. The findings support those of Stone et al (2001 Cognitive, Affective and Behavioral Neuroscience 1 183-191) and suggest that higher SCRs to famous faces are not necessarily due to covert recognition, but may be a response to the positive affective valence of the stimuli.