Out of sight, but not out of mind: a case study of the collaborative development of a university-wide orientation resource for online students.

The global online education sector has been rising rapidly, particularly during and after the events of 2020, and is becoming mainstream much sooner than expected. Despite this, research studies report higher levels of perceived isolation, difficulties with engagement, and higher attrition rates in online compared to equivalent on-campus programs. Reasons include restrictions to the type of institutional support accessible by online students, and the lack of comprehensiveness of orientation resources. This paper describes the collaborative efforts by a cross-faculty academic team, supported by a community of practice, to create a university-wide online orientation resource-the Monash Online Learning Hub (MOLH). The development of the MOLH involved multiple phases, including an analysis of current practice, resource design and content creation, formative evaluation by staff and students, and successful integration into the university's mainstream student orientation platform for widescale implementation. The methods adopted were varied, and involved generating both qualitative and quantitative data across multiple phases of development from online education experts at the University, that culminated in the gradual building and refinement of the MOLH. Final outcomes, implications and lessons learned are also discussed in this paper.

Retrograde Autobiographical Memory From PTA Emergence to Six-Month Follow-Up in Moderate to Severe Traumatic Brain Injury.

OBJECTIVE: The overwhelming focus of research on memory following traumatic brain injury (TBI) has been on anterograde amnesia, and very little attention has been paid to retrograde amnesia. There is evidence to suggest that retrograde autobiographical memory deficits exist after severe TBI, although there have been no prospective studies of autobiographical memory in a representative sample of moderate to severe cases recruited from hospital admissions. METHODS: The purpose of the present study was to report changes in autobiographical memory performance among a group of patients soon after emergence from posttraumatic amnesia (PTA) and at the 6-month follow-up compared with a healthy control (HC) group. The authors also examined associations with anterograde memory function and community integration to assist in understanding the functional impact of autobiographical memory deficits and potential underlying mechanisms. The Autobiographical Memory Interview and the Rey Auditory Verbal Learning Test were used as measures of retrograde and anterograde memory, respectively, and the Community Integration Questionnaire was used as a measure of functional outcome in the TBI group. RESULTS: The results demonstrated that both personal semantic and episodic autobiographical memory scores were impaired following emergence from PTA and at the 6-month follow-up. Only subtle differences emerged in change over time in different injury severity groups. Recent retrograde memory function was associated with anterograde memory performance, which supports some degree of overlap in underlying mechanisms. CONCLUSIONS: The findings suggest that autobiographical memory deficits are prevalent following moderate to severe TBI and warrant consideration in rehabilitation.

Setting priorities for health education research: A mixed methods study.

Introduction: Identifying priority research topics that meet the needs of multiple stakeholders should maximize research investment. Aim: To identify priorities for health education research. Methods: A three-stage sequential mixed methods study was conducted. Priorities for health education research were identified through a qualitative survey with 104 students, patients, academics, and clinicians across five health sciences and 12 professions (stage 1). These findings were analyzed using framework analysis and transposed into a quantitative survey whereby 780 stakeholders rated and ranked the identified priorities. Descriptive statistics identified priorities, exploratory factor analysis grouped priorities and differences between stakeholders were determined using Mann-Whitney U tests (stage 2). Six individual or group interviews with 16 participants (stage 3) further explicated the results from previous stages. Results: Of 30 priorities identified, the top were: how best to ensure students develop the required skills for work; how to promote resiliency and well-being in students; and ensuring the curriculum prepares students for work. For the majority of priorities, no significant differences were found between different stakeholder groups. Conclusions: These findings will be used to inform health educational research strategy both locally and nationally. Further research should explore if setting priorities can be translated effectively into education research policy and practice.

Retrograde Personal Semantic Memory During Post-Traumatic Amnesia and Following Emergence.

OBJECTIVES: Anecdotal reports suggest that following traumatic brain injury (TBI) retrograde memories are initially impaired and recover in order of remoteness. However, there has been limited empirical research investigating whether a negative gradient in retrograde amnesia-relative preservation of remote over recent memory-exists during post-traumatic amnesia (PTA) compared with the acute phase post-emergence. This study used a repeated-measures design to examine the pattern of personal semantic (PS) memory performance during PTA and within two weeks of emergence to improve understanding of the nature of the memory deficit during PTA and its relationship with recovery. METHODS: Twenty patients with moderate-severe TBI and 20 healthy controls (HCs) were administered the Personal Semantic Schedule of the Autobiographical Memory Interview. The TBI group was assessed once during PTA and post-emergence. Analysis of variance was used to compare the gradient across lifetime periods during PTA relative to post-emergence, and between groups. RESULTS: PS memory was significantly lower during PTA than post-emergence from PTA, with no relative preservation of remote memories. The TBI group was still impaired relative to HCs following emergence from PTA. Lower overall PS memory scores during PTA were associated with increased days to emerge from PTA post-interview. CONCLUSIONS: These results suggest a global impairment in PS memory across lifetime periods particularly during PTA, but still present within 2 weeks of emergence from PTA. PS memory performance may be sensitive to the diffuse nature of TBI and may, therefore, function as a clinically valuable indicator of the likely time to emerge from PTA. (JINS, 2018, 24, 1064-1072).

Interindividual variation in fornix microstructure and macrostructure is related to visual discrimination accuracy for scenes but not faces.

Transection of the nonhuman primate fornix has been shown to impair learning of configurations of spatial features and object-in-scene memory. Although damage to the human fornix also results in memory impairment, it is not known whether there is a preferential involvement of this white-matter tract in spatial learning, as implied by animal studies. Diffusion-weighted MR images were obtained from healthy participants who had completed versions of a task in which they made rapid same/different discriminations to two categories of highly visually similar stimuli: (1) virtual reality scene pairs; and (2) face pairs. Diffusion-MRI measures of white-matter microstructure [fractional anisotropy (FA) and mean diffusivity (MD)] and macrostructure (tissue volume fraction, f) were then extracted from the fornix of each participant, which had been reconstructed using a deterministic tractography protocol. Fornix MD and f measures correlated with scene, but not face, discrimination accuracy in both discrimination tasks. A complementary voxelwise analysis using tract-based spatial statistics suggested the crus of the fornix as a focus for this relationship. These findings extend previous reports of spatial learning impairments after fornix transection in nonhuman primates, critically highlighting the fornix as a source of interindividual variation in scene discrimination in humans.

A critical role for the hippocampus and perirhinal cortex in perceptual learning of scenes and faces: complementary findings from amnesia and FMRI.

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 > 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 functional region-of-interest analyses, was modulated by accuracy (correct > incorrect within a preferred category). Therefore, both approaches revealed a key role for the HC and PrC in discrimination learning, which is consistent with representational accounts in which subregions in these MTL structures store complex spatial and object representations, respectively.

Traumatic brain injury alters the relationship between brain structure and episodic memory.

BACKGROUND: Focal and diffuse pathology resulting from traumatic brain injury (TBI) often disrupts brain circuitry that is critical for episodic memory, including medial temporal lobe and prefrontal regions. Prior studies have focused on unitary accounts of temporal lobe function, associating verbally learned material and brain morphology. Medial temporal lobe structures, however, are domain-sensitive, preferentially supporting different visual stimuli. There has been little consideration of whether TBI preferentially disrupts the type of visually learned material and its association with cortical morphology following injury. Here, we investigated whether (1) episodic memory deficits differ according to the stimulus type, and (2) the pattern in memory performance can be linked to changes in cortical thickness. METHODS: Forty-three individuals with moderate-severe TBI and 38 demographically similar healthy controls completed a recognition task in which memory was assessed for three categories of stimuli: faces, scenes, and animals. The association between episodic memory accuracy on this task and cortical thickness was subsequently examined within and between groups. RESULTS: Our behavioral results support the notion of category-specific impairments: the TBI group had significantly impaired accuracy for memory for faces and scenes, but not animals. Moreover, the association between cortical thickness and behavioral performance was only significant for faces between groups. CONCLUSION: Taken together, these behavioral and structural findings provide support for an emergent memory account, and highlight that cortical thickness differentially affects episodic memory for specific categories of stimuli.

A Self-Managed Online Mindfulness Program in a University-Wide Learning Management System Orientation Site: A Real-World Ecological Validation Study.

The efficacy of mindfulness-based interventions in randomised-controlled trials and large experimental studies has been demonstrated in university student populations. Whilst these investigations have provided insight into the nature of the delivery of mindfulness-based practices, there has been little research in the implementation of self-managed online student wellbeing and mindfulness programs at university. This ecological validation study conducted in 2020 evaluated a real-world implementation of a large, university-wide, online mindfulness-based program that was accessible fully online via the tertiary institutions' Learning Management System (LMS) student orientation site. The total sample included 833 participants from a range of disciplines and faculties at Monash University, Australia. At the end of the study, 236 (28.3%) participants were retained and completed the follow-up survey. Participants had the option to engage with the fully self-managed online mindfulness program for a 12-week semester. The mindfulness practices were pre-recorded, audio-guided sessions, and 10-15 min in length. Baseline and end of semester questionnaires included the 14-item Warwick-Edinburgh Mental Wellbeing Scale, 10-item Perceived Stress Scale and the 18-item Five Facet Mindfulness Questionnaire. Participants who engaged with the mindfulness program over 3 or more weeks showed significant improvements in all three outcome measures, and all participants showed significant improvements in wellbeing at the end of semester. Learning analytics obtained via the LMS revealed that 58.6% (n = 489) had not logged into the mindfulness program at all, almost a third (31.0%, n = 259) logged into the program materials once or twice, and 10.2% (n = 85) of the whole sample engaged with the program actively, having logged in three or more times. The total number of student logins peaked in week 2, reduced between week 2 and week 7 and thereafter activity remained stable until the end of the semester. We hypothesise that the changes in wellbeing, stress and mindfulness at the end of the semester seen in the low engagement participants may partly be explained by the circumstances of COVID-19 restrictions improving. This study has revealed and discusses the complexities of student behaviour and implications for implementing an online mindfulness program in the real- world setting of a university.

Immersive virtual reality simulated learning environment versus role-play for empathic clinical communication training.

INTRODUCTION: The use of immersive virtual reality simulated learning environments (VR SLEs) for improving clinical communication can offer desirable qualities including repetition and determinism in a safe environment. The aim of this study was to establish whether the mode of delivery, VR SLE versus clinical role-play, could have a measurable effect on clinical empathic communication skills for MRI scenarios. METHODS: A split-cohort study was performed with trainee practitioners (n = 70) and qualified practitioners (n = 9). Participants were randomly assigned to four groups: clinician VR (CVR), clinician role-play (CRP), trainee VR (TVR), and trainee RP (TRP). Clinical communication skills were assessed using two methods: firstly, a self-reported measure - the SE-12 communication questionnaire and, secondly, a training and assessment tool developed by a panel of experts. RESULTS: Participants in the VR trainee (TVR) and clinician (CVR) groups reported 11% (P < 0.05) and 7.2% (P < 0.05) improvements in communication confidence post training, whereas trainees assigned to the role-play (TRP) intervention reported a 4.3% (P < 0.05) improvement. Empirical assessment of communication training scores assessing a participant's ability to select empathic statements showed the TVR group performed 5% better on average than their role-play counterparts (P < 0.05). CONCLUSION: The accuracy of participant's selection of appropriate empathic responses was shown to differ significantly following the training intervention designed to improve interactions with patients that present for an MRI scan. The results may demonstrate the capacity for immersion into an emotional narrative in a VR environment to increase the user's susceptibility for recalling and selecting empathic terminology.

Temporal lobe activation during episodic memory encoding following traumatic brain injury.

The temporal lobes are critical for encoding and retrieving episodic memories. The temporal lobes are preferentially disrupted following a traumatic brain injury (TBI), likely contributing to the difficulties observed in episodic memory. However, the underlying neural changes that precipitate or maintain these difficulties in individuals with TBI remains poorly understood. Here, we use functional magnetic resonance imaging (fMRI) to interrogate the relationship between temporal lobe activation and encoding of episodic stimuli. Participants encoded face, scene, and animal stimuli during an fMRI run. In an out-of-scanner task, participants were required to correctly identify previously displayed stimuli over two presentation runs (each in-scanner stimuli presented twice). Forty-three patients with moderate-severe TBI were recruited and compared with 38 demographically similar healthy controls. The pattern of behavioural performance between groups depended on the stimuli presentation run. The TBI group demonstrated poorer episodic memory for faces and scenes during the first presentation, but not the second presentation. When episodic memory was analysed across all presentation runs, behavioural deficits were only apparent for faces. Interestingly, processing of faces emerged as the only between group-difference on fMRI, whereby TBI participants had an increased signal in the middle temporal gyrus extending to the superior temporal sulcus. These findings provide evidence to suggest that following TBI: (a) episodic memory is preferentially impaired for complex stimuli such as faces, and (b) robust behavioural inefficiencies are reflected in increased activation in specific temporal lobe structures during encoding.

Aberrant modulation of brain activity underlies impaired working memory following traumatic brain injury.

Impaired working memory is a common and disabling consequence of traumatic brain injury (TBI) that is caused by aberrant brain processing. However, little is known about the extent to which deficits are perpetuated by specific working memory subprocesses. Using a combined functional magnetic resonance imaging (fMRI) and working memory paradigm, we tested the hypothesis that the pattern of brain activation subserving working memory following TBI would interact with both task demands and specific working memory subcomponents: encoding, maintenance, and retrieval. Forty-three patients with moderate-severe TBI, of whom 25 were in the acute phase of recovery (M = 2.16 months, SD = 1.48 months, range = 0.69 - 6.64 months) and 18 in the chronic phase of recovery (M = 23.44 months, SD = 6.76 months, range = 13.35 - 34.82 months), were compared with 38 demographically similar healthy controls. Behaviourally, we found that working memory deficits were confined to the high cognitive load trials in both acute (P = 0.006) and chronic (P = 0.024) cohorts. Furthermore, results for a subset of the sample (18 chronic TBI and 17 healthy controls) who underwent fMRI revealed that the TBI group showed reduced brain activation when simply averaged across all task trials (regardless of cognitive load or subcomponent). However, interrogation of the subcomponents of working memory revealed a more nuanced pattern of activation. When examined more closely, patterns of brain activity following TBI were found to interact with both task demands and the working memory subcomponent: increased activation was observed during encoding in the left inferior occipital gyrus whereas decreased activation was apparent during maintenance in the bilateral cerebellum and left calcarine sulcus. Taken together, findings indicate an inability to appropriately modulate brain activity according to task demand that is specific to working memory encoding and maintenance.

Psychology Education and Work Readiness Integration: A Call for Research in Australia.

Supporting students to develop transferable skills and gain employment is a vital function of Universities in the era of the Fourth Industrial Revolution. A key area is work readiness, which has steadily grown in importance over the last 2 decades as tertiary institutions increasingly aim to produce graduates who perceive and are perceived as work ready. However, a large majority of graduates report a lack of skills and confidence needed for the effective transition from study to work. This may be particularly problematic for disciplines that impart both discipline-specific and transferrable skills, such as psychology. The aim of this paper is to addresses the concept of work readiness within Australian psychological training and explores the need to shed light on and integrate work readiness within the pedagogy of psychology within Australia. Specifically, this paper calls for a review of work readiness skills developed in psychological courses to ensure industry needs are met. Beyond such a review, it is suggested that tertiary centres need to facilitate students in capturing and reflecting upon the transferable skills that they develop; and build assessments that allow students to demonstrate transferable skills in a meaningful way. Further, this paper proposes that work readiness skills be routinely mapped onto graduate attributes and course learning outcomes to be readily available by students so as to increase students' potential to articulate their learnt work readiness skills once in the workplace.

An Evaluation of an Online Brief Mindfulness-Based Intervention in Higher Education: A Pilot Conducted at an Australian University and a British University.

Mental ill health among higher education students is a well-established problem; therefore, it is imperative to implement preventative approaches to support wellbeing. Blended and fully online education programmes widens access for mature or returning students; however, the psychological wellbeing of this sub-group of students is under-researched. Finally, evaluating wellbeing interventions that meet the needs of university students as well as accessible for online students is required. The aim of this study was to evaluate a brief, online and mindfulness-based intervention to assist the self-management of wellbeing and stress for both online and on-campus higher education students. The total sample included 427 participants (96% psychology students) at Monash University, Australia (n=283) and King's College London (n=144), with 152 participants completing the whole study. Participants were allocated to a brief, self-guided, online and mindfulness-based intervention (over the course of one study period; n=297), or to a wait-list control group (n=148). Baseline and end of semester questionnaires included the 14-item Warwick-Edinburgh Mental Wellbeing Scale, 10-item Perceived Stress Scale and the 15-item Mindful Attention Awareness Scale. Regression modelling revealed the intervention condition accounted for up to 12% of the variability in change in student wellbeing, stress and mindfulness between the start and end of semester (when controlling for baseline). These findings support the implementation of a brief, online and asynchronous mindfulness-based intervention for supporting student mental health and psychological wellbeing. An on-going challenge in practice includes engaging and maintaining student engagement in wellbeing initiatives.

Metacognitive Accuracy Improves With the Perceptual Learning of a Low- but Not High-Level Face Property.

Experience with visual stimuli can improve their perceptual performance, a phenomenon termed visual perceptual learning (VPL). VPL has been found to improve metacognitive measures, suggesting increased conscious accessibility to the knowledge supporting perceptual decision-making. However, such studies have largely failed to control objective task accuracy, which typically correlates with metacognition. Here, using a staircase method to control this confound, we investigated whether VPL improves the metacognitive accuracy of perceptual decision-making. Across 3 days, subjects were trained to discriminate faces based on their high-level identity or low-level contrast. Holding objective accuracy constant across training days, perceptual thresholds decreased in both tasks, demonstrating VPL in our protocol. However, whilemetacognitive accuracy was not affected by face contrast VPL, it was decreased by face identity VPL. Our findings couldbe parsimoniously explained by a dual-stage signal detection theory-based model involving an initial perceptual decision-making stage and a second confidence judgment stage. Within this model, internal noise reductions for both stages accounts for our face contrast VPL result, while only first stage noise reductions accounts for our face identity VPL result. In summary, we found evidence suggesting that conscious knowledge accessibility was improved by the VPL of face contrast but not face identity.

Quantification of Student Radiographic Patient Positioning Using an Immersive Virtual Reality Simulation.

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.

Prospective evaluation of first and last memory reports following moderate to severe traumatic brain injury.

Prospective monitoring of posttraumatic amnesia (PTA) status is recommended following traumatic brain injury (TBI). Use of patients' subjective reports is, however, still common and necessary in some circumstances. It is therefore important to understand how patients' self-reported first memories relate to prospective measures and how reliable these reports remain over time. In the present study, patients with moderate-severe TBI in PTA were asked about their first and last memories surrounding the injury daily and were administered the Westmead Post-Traumatic Amnesia Scale (WPTAS). Following PTA emergence, a semistructured interview was used to ascertain participants' reports of return of continuous memory after the injury, as well as their last preinjury memory. This interview was repeated six months later, along with the Community Integration Questionnaire to measure functional outcome and the Rey Auditory Verbal Learning Test to measure anterograde memory. The temporal order of recovery of WPTAS variables and subjective reports was determined, and consistency of subjective reports over time was examined using bivariate correlation and intraclass correlation coefficients (ICCs). Findings suggested that patients' reports of return of continuous memory aligned most closely with return of consistent orientation, and occurred significantly earlier than attainment of criterion on the WPTAS. Reported first memories were significantly later at follow-up (i.e., greater days post injury) and the ICC was not suggestive of adequate clinical reliability. Last memory reports were slightly more reliable, with 71% of cases remaining in the same band at follow-up. Demographic and injury-related variables were not significantly associated with the discrepancy between reports. The variability in patients' reports over time highlights the importance and value of prospective PTA monitoring.

Parameters of visual processing abnormalities in adults with body image concerns.

Body dysmorphic disorder (BDD), at the extreme end of the body image concern (BIC) spectrum, is thought to be associated with a local (detail-focussed) visual processing bias. Given that the inversion of a stimulus disrupts holistic processing and demands detail-specific attention, this perceptual bias is characterised by superior processing of such inverted stimuli. This study examined the processing bias, via a body-inversion discrimination task, of 26 participants with non-clinical, high-BIC (Dysmophic Concern Questionnaire (DCQ) scores between 11-19) and 26 participants with low-BIC (DCQ scores between 0-4). This study also explored the impact of varying stimuli presentation durations and discrimination difficulties during the inversion task on visual processing. As hypothesised, compared to those with low-BIC, participants with high-BIC demonstrated superior accuracy when discriminating between images of inverted bodies, indicating a local processing bias. Also as hypothesised, this local processing bias selectively manifested only when stimuli were presented for longer durations and at higher discrimination difficulties, revealing the parameters of this, potentially conscious, processing tendency. Consistent with previous research, this study identified a local processing bias in those with high BIC, which may be a predisposing factor for developing BDD. In turn, identifying the parameters (stimulus exposure and stimulus complexity) in which the local bias manifests has implications for future interventions aiming to reverse this perceptual abnormality.

Altering Visual Perception Abnormalities: A Marker for Body Image Concern.

The body image concern (BIC) continuum ranges from a healthy and positive body image, to clinical diagnoses of abnormal body image, like body dysmorphic disorder (BDD). BDD and non-clinical, yet high-BIC participants have demonstrated a local visual processing bias, characterised by reduced inversion effects. To examine whether this bias is a potential marker of BDD, the visual processing of individuals across the entire BIC continuum was examined. Dysmorphic Concern Questionnaire (DCQ; quantified BIC) scores were expected to correlate with higher discrimination accuracy and faster reaction times of inverted stimuli, indicating reduced inversion effects (occurring due to increased local visual processing). Additionally, an induced global or local processing bias via Navon stimulus presentation was expected to alter these associations. Seventy-four participants completed the DCQ and upright-inverted face and body stimulus discrimination task. Moderate positive associations were revealed between DCQ scores and accuracy rates for inverted face and body stimuli, indicating a graded local bias accompanying increases in BIC. This relationship supports a local processing bias as a marker for BDD, which has significant assessment implications. Furthermore, a moderate negative relationship was found between DCQ score and inverted face accuracy after inducing global processing, indicating the processing bias can temporarily be reversed in high BIC individuals. Navon stimuli were successfully able to alter the visual processing of individuals across the BIC continuum, which has important implications for treating BDD.

Testing day: The effects of processing bias induced by Navon stimuli on the strength of the Müller-Lyer illusion.

Explanations for the cognitive basis of the Müller-Lyer illusion are still frustratingly mixed. To date, Day's (1989) theory of perceptual compromise has received little empirical attention. In this study, we examine the merit of Day's hypothesis for the Müller-Lyer illusion by biasing participants toward global or local visual processing through exposure to Navon (1977) stimuli, which are known to alter processing level preference for a short time. Participants (N = 306) were randomly allocated to global, local, or control conditions. Those in global or local conditions were exposed to Navon stimuli for 5 min and participants were required to report on the global or local stimulus features, respectively. Subsequently, participants completed a computerized Müller-Lyer experiment where they adjusted the length of a line to match an illusory-figure. The illusion was significantly stronger for participants with a global bias, and significantly weaker for those with a local bias, compared with the control condition. These findings provide empirical support for Day's "conflicting cues" theory of perceptual compromise in the Müller-Lyer illusion.

Brain correlates of experience-dependent changes in stimulus discrimination based on the amount and schedule of exposure.

One product of simple exposure to similar visual stimuli is that they become easier to distinguish. The early visual cortex and other brain areas (such as the prefrontal cortex) have been implicated in such perceptual learning effects, but the anatomical specificity within visual cortex and the relationship between sensory cortex and other brain areas has yet to be examined. Moreover, while variations in the schedule (rather than merely the amount) of exposure influence experience-dependent improvement in discrimination, the neural sequelae of exposure schedule have not been fully investigated. In an event-related fMRI study, participants were exposed to confusable pairs of faces, scenes and dot patterns, using either intermixed or blocked presentation schedules. Participants then performed same/different judgements with exposed and novel pairs of stimuli. Stimulus independent activation, which was correlated with experience-dependent improvement in discrimination, was seen in frontal areas (e.g. frontal and supplementary eye fields and dorsolateral prefrontal cortex) and in early visual cortex (V1-4). In all regions, the difference in activation between exposed and novel stimuli decreased as a function of the degree of discrimination improvement. Overall levels of BOLD activation differed across regions, consistent with the possibility that, as a consequence of experience, processing shifts from initial engagement of early visual regions to higher order visual areas. Similar relationships were observed when contrasting intermixed with blocked exposure, suggesting that the schedule of exposure primarily influences the degree of, rather than the mechanisms for, discrimination performance.