Human participants received unsupervised exposure to difficult-to-discriminate stimuli (e.g., A and A'), created with a morphing procedure from photographs of faces, before learning a discrimination between them. Experiments 1 and 2 demonstrated that prior exposure enhanced later discrimination and that intermixed exposure (A, A', A, A'...) resulted in better subsequent discrimination than blocked exposure (B, B, ...B', B'...). Experiments 3 and 4 showed that simultaneous exposure to 2 similar stimuli facilitated the later acquisition of both a simultaneous and a successive discrimination, and this effect was observed even though simultaneous exposure to 2 stimuli fostered the development of an excitatory association between them (Experiment 5). The findings of Experiments 1 and 2 revealed a perceptual learning effect with pictures of faces, and the findings of Experiments 3-5 are difficult to reconcile with associative analyses of perceptual learning.

Demand for flexible online offerings has continued to increase as prospective students seek to upskill, re-train, and undertake further study. Education institutions are moving to intensive modes of online study delivered in 6-to 8-week study periods which offer more frequent intake periods. Prior literature has established key success factors for nonintensive (12-13 weeks) online offerings; for teachers, skill development is critical to promote a flexible, responsive approach and maintain technological capabilities; for students, an ability to navigate the technology, interact with the learning environment in meaningful ways, and self-regulate learning is important, as the absence of physical infrastructure and opportunities for face-to-face interactions in online environments places a greater emphasis on alternate forms of communication and support. The current paper explores known best practice principles for online instructors, students, and student support and considers how these might apply to intensive online environments. It is suggested that the accelerated nature of learning in intensive settings may place additional demands on students, instructors, and support mechanisms. Further research is imperative to determine predictors of success in online intensive learning environments.

It is debated whether subregions within the medial temporal lobe (MTL), in particular the hippocampus (HC) and perirhinal cortex (PrC), play domain-sensitive roles in learning. In the present study, two patients with differing degrees of MTL damage were first exposed to pairs of highly similar scenes, faces, and dot patterns and then asked to make repeated same/different decisions to preexposed and nonexposed (novel) pairs from the three categories (Experiment 1). We measured whether patients would show a benefit of prior exposure (preexposed Ͼ nonexposed) and whether repetition of nonexposed (and preexposed) pairs at test would benefit discrimination accuracy. Although selective HC damage impaired learning of scenes, but not faces and dot patterns, broader MTL damage involving the HC and PrC compromised discrimination learning of scenes and faces but left dot pattern learning unaffected. In Experiment 2, a similar task was run in healthy young participants in the MRI scanner. Functional region-of-interest analyses revealed that posterior HC and posterior parahippocampal gyrus showed greater activity during scene pattern learning, but not face and dot pattern learning, whereas PrC, anterior HC, and posterior fusiform gyrus were recruited during discrimination learning for faces, but not scenes and dot pattern learning. Critically, activity in posterior HC and PrC, but not the other functionalregion-of-interestanalyses,wasmodulatedbyaccuracy(correctϾincorrectwithinapreferredcategory).Therefore,bothapproaches revealedakeyrolefortheHCandPrCindiscriminationlearning,whichisconsistentwithrepresentationalaccountsinwhichsubregionsinthese MTL structures store complex spatial and object representations, respectively.

Individuals with body dysmorphic disorder (BDD) appear to possess abnormalities in the way they observe and discriminate visual information. A pre-occupation with perceived defects in appearance has been attributed to a local visual processing bias. We studied the nature of visual bias in individuals who may be at risk of developing BDD – those with high body image concerns (BICs) – by using inverted stimulus discrimination. Inversion disrupts global, configural information in favor of local, feature-based processing. 40 individuals with high BIC and 40 low BIC controls performed a discrimination task with upright and inverted faces, bodies, and scenes. Individuals with high BIC discriminated inverted faces and bodies faster than controls, and were also more accurate when discriminating inverted bodies and scenes. This reduction in inversion effect for high BIC individuals may be due to a stimulus-general local, detail-focused processing bias, which may be associated with maladaptive fixation on small features in their appearance.

Perceptual learning in humans was examined in 2 experiments. In Experiment 1, participants received intermixed exposure to 2 similar compounds (AX, BX, AX, BX, . . .) and blocked exposure to a 2nd pair of similar compounds (CY, CY, . . . , DY, DY, . . .). Aversions established to AX and CY generalized less to BX than to DY. In Experiment 2, 1 pair of compounds was presented in a forward order (i.e., AX3BX), whereas the 2nd pair of compounds was presented in a backward order (i.e., DY-->CY). Aversions established to AX and CY generalized less to BX than to DY. These results indicate that inhibitory associations contribute to perceptual learning in humans and thereby establish a fundamental similarity between the mechanisms that underlie perceptual learning in humans and rats.

Within-subjects procedures were used to assess the influence of stimulus comparison on perceptual learning in humans. In Experiment 1, participants received intermixed (A, A', A, A',…) or blocked (B, B,…, B', B',…) exposure to pairs of similar female faces. In a subsequent same/different discrimination task, participants were more accurate when the test involved A and A' than when it involved B and B' (or novel faces: C and C'). This perceptual learning effect was reduced by placing a visual distractor (*: either another face or a checkerboard) between successive presentations of the faces during the exposure stage (e.g., A - * - A'). The attenuation of the intermixed versus blocked difference was particularly marked when faces were used as the distractor. In Experiment 2, this reduction in perceptual learning was more marked when * was positioned between the pairs of intermixed faces (i.e., A - * - A') than when it preceded and succeeded those faces (i.e., * - A - A' - *). These results provide the first direct evidence that the opportunity to compare stimuli plays a causal role in supporting perceptual learning. They also support the specific view that perceptual learning reflects an interaction between a short-term habituation process, that ordinarily biases processing away from the frequently presented common elements and toward their less frequently presented unique elements, and a long-term representational process that reflects this bias.

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Introduction Immersive virtual reality (VR) simulation environments facilitate novel ways for users to visualize anatomy and quantify performance relative to expert users. The ability of software to provide positional feedback before a practitioner progresses with subsequent stages of examinations has broad implications for primary and allied healthcare professionals, particularly with respect to health and safety (eg, exposing to x-rays). The effect of training student-radiographers (radiology technicians), with a VR simulation environment was quantitatively assessed. Methods Year 1 radiography students (N = 76) were randomly split into 2 cohorts, each of which were trained at performing the same tasks relating to optimal hand positioning for projection x-ray imaging; group 1 was trained using the CETSOL VR Clinic software, whereas group 2 was trained using conventional simulated role-play in a real clinical environment. All participants completed an examination 3 weeks after training. The examination required both posterior-anterior and oblique hand x-ray positioning tasks to be performed on a real patient model. The analysis of images from the examination enabled quantification of the students' performance. The results were contextualized through a comparison with 4 expert radiographers. Results Students in group 1 performed on average 36% (P < 0.001) better in relation to digit separation, 11% (P ≤ 0.001) better in terms of palm flatness and 23% (P < 0.05) better in terms of central ray positioning onto the third metacarpal. Conclusion A significant difference in patient positioning was evident between the groups; the VR clinic cohort demonstrated improved patient positioning outcomes. The observed improvement is attributed to the inherent task deconstruction and variety of visualization mechanisms available in immersive VR environments.