Teaching through their eyes: effects on optometry teachers' adaptivity and students' learning when teachers see students' gaze

Adaptive teacher support fosters effective learning in one-to-one teaching sessions, which are a common way of learning complex visual tasks in the health sciences. Adaptive support is tailored to student needs, and this is difficult in complex visual tasks as visual problem-solving processes are covert and thus cannot be directly observed by the teacher. Eye-tracking apparatus can measure covert processes and make them visible in gaze displays: visualizations of where a student looks while executing a task. We investigate whether live dynamic gaze displays help teachers in being more adaptive to students' needs when teaching optical coherence tomography interpretation in one-to-one teaching sessions and whether this fosters learning. Forty-nine students and 10 teachers participated in a one-to-one teaching session in clinical optometry. In the control condition, teachers saw the learning task of the student and could discuss it with them, whereas in the gaze-display condition, teachers could additionally see where the student looked. After the 15-minute teaching session, a test was administered to examine achievement. Furthermore, students filled in the 'questionnaire on teacher support adaptivity', and teachers rated how adaptive their support was. Bayesian analyses provide some initial evidence that students did not experience support to be more adaptive in the gaze-display condition versus the control condition, nor were their post-test scores higher. Teachers rated their provided support as being more adaptive in the gaze-display versus the control condition. Further research could investigate if live dynamic gaze displays impact adaptive teaching when used over longer periods or with more teacher training.

Visualizing a Task Performer’s Gaze to Foster Observers’ Performance and Learning—a Systematic Literature Review on Eye Movement Modeling Examples

Eye movement modeling examples (EMMEs) are instructional videos (e.g., tutorials) that visualize another person’s gaze location while they demonstrate how to perform a task. This systematic literature review provides a detailed overview of studies on the effects of EMME to foster observers’ performance and learning and highlights their differences in EMME designs. Through a broad, systematic search on four relevant databases, we identified 72 EMME studies (78 experiments). First, we created an overview of the different study backgrounds. Studies most often taught tasks from the domains of sports/physical education, medicine, aviation, and STEM areas and had different rationales for displaying EMME. Next, we outlined how studies differed in terms of participant characteristics, task types, and the design of the EMME materials, which makes it hard to infer how these differences affect performance and learning. Third, we concluded that the vast majority of the experiments showed at least some positive effects of EMME during learning, on tests directly after learning, and tests after a delay. Finally, our results provide a first indication of which EMME characteristics may positively influence learning. Future research should start to more systematically examine the effects of specific EMME design choices for specific participant populations and task types.

Expertise development in volumetric image interpretation of radiology residents: what do longitudinal scroll data reveal?

The current study used theories on expertise development (the holistic model of image perception and the information reduction hypothesis) as a starting point to identify and explore potentially relevant process measures to monitor and evaluate expertise development in radiology residency training. It is the first to examine expertise development in volumetric image interpretation (i.e., CT scans) within radiology residents using scroll data collected longitudinally over five years of residency training. Consistent with the holistic model of image perception, the percentage of time spent on full runs, i.e. scrolling through more than 50% of the CT-scan slices (global search), decreased within residents over residency training years. Furthermore, the percentage of time spent on question-relevant areas in the CT scans increased within residents over residency training years, consistent with the information reduction hypothesis. Second, we examined if scroll patterns can predict diagnostic accuracy. The percentage of time spent on full runs and the percentage of time spent on question-relevant areas did not predict diagnostic accuracy. Thus, although scroll patterns over training years are consistent with visual expertise theories, they could not be used as predictors of diagnostic accuracy in the current study. Therefore, the relation between scroll patterns and performance needs to be further examined, before process measures can be used to monitor and evaluate expertise development in radiology residency training.

Optimizing self-regulation of performance: is mental effort a cue?

Accurate self-regulation of performance is important for trainees. Trainees rely on cues to make monitoring judgments to self-regulate their performance. Ideally, cues and monitoring judgements accurately reflect performance, as measured by cue diagnosticity (the ability of a cue to predict performance) and monitoring accuracy (the ability of a monitoring judgement to predict performance). However, this process is far from perfect, emphasizing the need for more accurate cues and monitoring judgements. Perhaps the mental effort of a task could be a cue used to inform certainty judgements. The purpose of this study is to measure cue utilization and cue diagnosticity of mental effort and monitoring accuracy of certainty for self-regulation of performance. Focused on the task of ECG interpretation, 22 PGY 1-3 Internal Medicine residents at McMaster University provided a diagnosis for 10 ECGs, rating their level of certainty (0-100%) and mental effort (Paas scale, 1-9). 220 ECGs completed by 22 participants were analyzed using path analysis. There was a negative moderate path coefficient between certainty and mental effort (β = - 0.370, p < 0.001), reflecting cue utilization. Regarding cue diagnosticity of mental effort, this was reflected in a small negative path coefficient between mental effort and diagnostic accuracy (β = - 0.170, p = 0.013). Regarding monitoring accuracy, a moderate path coefficient was observed between certainty and diagnostic accuracy (β = 0.343, p < 0.001). Our results support mental effort as a cue and certainty as a monitoring judgement for self-regulated performance. Yet, reported correlations are not very high. Future research is needed to identify additional cues.

The Neural Implementation of Surgical Expertise Within the Mirror-Neuron System: An fMRI Study

Motor expertise is an important aspect of high-level performance in professional tasks such as surgery. While recently it has been shown that brain activation as measured by functional magnetic resonance imaging (fMRI) within the mirror-neuron system (MNS) is modulated by expertise in sports and music, little is known about the neural underpinnings of professional, e.g., surgical expertise. Here, we investigated whether and (if so) how surgical expertise is implemented in the MNS in medical professionals across three levels of surgical qualification. In order to answer the more specific research question, namely, if the neural implementation of motor expertise develops in a linear or non-linear fashion, the study compares not only brain activation within the MNS related to action observation of novices and experts, but also intermediates. Ten novices (medical students), ten intermediates (residents in orthopedic surgery) and ten experts (orthopedic surgeons) watched 60 video clips (5 s each) of daily-life activities and surgical procedures each while their brain activation was measured using a 3-T fMRI scanner. An established localization procedure was followed to functionally define the MNS for each participant individually. A 2 (video type: daily-life activities, surgical procedures) × 3 (expertise level: novice, intermediate, expert) ANOVA yielded a non-significant interaction. Furthermore, separate analyses of the precentral and parietal part of the MNS also yielded non-significant interactions. However, post hoc comparisons showed that intermediates displayed marginally significantly lower brain activation in response to surgery-related videos within the MNS than novices. No other significant differences were found. We did not find evidence for the hypothesis that the brain-activation level in the MNS evoked by observing surgical videos reflects the level of surgical expertise in the professional task of (orthopedic) surgery. However, the results suggest a potential non-linear relationship between expertise level and MNS-activation level.

The challenges of studying visual expertise in medical image diagnosis

CONTEXT

Visual expertise is the superior visual skill shown when executing domain-specific visual tasks. Understanding visual expertise is important in order to understand how the interpretation of medical images may be best learned and taught. In the context of this article, we focus on the visual skill of medical image diagnosis and, more specifically, on the methodological set-ups routinely used in visual expertise research.

METHODS

We offer a critique of commonly used methods and propose three challenges for future research to open up new avenues for studying characteristics of visual expertise in medical image diagnosis. The first challenge addresses theory development. Novel prospects in modelling visual expertise can emerge when we reflect on cognitive and socio-cultural epistemologies in visual expertise research, when we engage in statistical validations of existing theoretical assumptions and when we include social and socio-cultural processes in expertise development. The second challenge addresses the recording and analysis of longitudinal data. If we assume that the development of expertise is a long-term phenomenon, then it follows that future research can engage in advanced statistical modelling of longitudinal expertise data that extends the routine use of cross-sectional material through, for example, animations and dynamic visualisations of developmental data. The third challenge addresses the combination of methods. Alternatives to current practices can integrate qualitative and quantitative approaches in mixed-method designs, embrace relevant yet underused data sources and understand the need for multidisciplinary research teams.

CONCLUSION

Embracing alternative epistemological and methodological approaches for studying visual expertise can lead to a more balanced and robust future for understanding superior visual skills in medical image diagnosis as well as other medical fields.

Through rose-coloured glasses: An empirical test of narcissistic overestimation

BACKGROUND

Grandiosity is designated as a hallmark trait of narcissism. The current study tested whether narcissistic traits are related to overestimation of a range of agentic performances.

METHOD

Eighty-five non-patients executed six objective tasks to assess their level of (emotional) intelligence, first impression, attractiveness, social skills and learning performance. They were also asked to estimate their level of functioning in these six areas. This estimation was given on two moments: before and after performing the objective tasks. Our main variable of interest was the degree to which subjective estimation exceeds objective scores.

RESULTS

Narcissistic traits were related to overestimation of (emotional) intelligence, attractiveness and social skills, particularly at a global level before performing the tasks.

LIMITATIONS

The use of a homogenous student sample; Mainly agentic performances, were studied.

CONCLUSION

Overall, the findings provide a theoretical validation of unwarranted feelings of grandiosity as a core narcissistic criterion. Copyright © 2016 John Wiley & Sons, Ltd.

Diabetic foot ulcers and amputations: estimates of health utility for use in cost-effectiveness analyses of new treatments

OBJECTIVES

Diabetic foot ulcers (DFU), infections and amputations are associated with high costs of care and loss of health. To evaluate new treatments, both the extra costs incurred and the health utility gained need to be examined. However, evaluations of treatments in diabetes are hampered by the lack of utility values for health states such as DFU. We estimated utility values for health states seen amongst DFU patients.

METHODS

We identified 13 unique health states based on presence/type of DFU and amputation. Members of the general public (n=107) received a description of each health state. They were then asked to indicate how undesirable each health state was (using the time trade-off method). Each answer was then transformed to create a value representing the "utility" of the health state, the utility value represented on a 0-1 scale.

RESULTS

Valid responses could be obtained from 96 persons. Mean values included: 0.84 (diabetes with no DFU or amputation), 0.75 (uninfected DFU, no amputation), 0.68 (no DFU, previous foot amputation), and 0.63 (uninfected DFU, previous amputation of other foot). The impact of an ulcer depended on amputation status.

CONCLUSIONS

Our values correspond with previously published results but are more detailed. In addition, since our values were derived from the general public, economic evaluations that incorporate them will use the generally preferred societal perspective. Therefore, these values are appropriate, practical and sensitive weights to calculate QALYs for cost-effectiveness analyses of foot ulcer treatments.

Lower urinary tract symptoms suggestive of benign prostatic obstruction--Triumph: health-economical analysis

Given the ageing of western populations, the cost burden associated with the treatment of LUTS suggestive of BPO will increase substantially over the next few decades. Therefore, from the economic perspective, the primary objective of the Triumph project is the assessment of the cost-effectiveness of treatment options for lower urinary tract symptoms (LUTS) suggestive of benign prostatic obstruction (BPO), formerly referred to as symptomtic benign prostatic hyperplasia (BPH), in medical practice in initially six European countries. All modalities of LUTS treatment used in these countries will be considered. The effectiveness and costs associated with these treatments will be assessed in each country. Data will be gathered from observed medical practice rather than in the setting of a trial. Country-specific aspects will be studied and the outcome of country-specific policies can be predicted. Patient quality of life will also be measured using the I-PSS score as a basis. A number of treatment scenarios will be assessed in terms of both their costs and long-term effects, using a computer simulation. These economic analyses will provide greatly improved insight into the most cost-effective treatments for LUTS suggestive of BPO.

The sequential appearance of components of the synaptonemal complex during meiosis of the female rat

This paper describes the light microscopy (LM) and electron microscopy (EM) localization of synaptonemal complex (SC) antigens in oocytes of rats. For this purpose, we used monoclonal antibodies (Mabs) that recognize components of 30 + 33, 125, and 190 kDa antigens of SCs of rat spermatocytes. The LM localization was performed by immunofluorescence and the EM localization by immunogold staining. The reaction of the Mabs with oocytes was similar to the reaction with spermatocytes, but weaker. The 30 + 33 kDa as well as the 190 kDa antigens could always be demonstrated if axial elements of the SC were present, irrespective of whether these were paired or unpaired. Thus, these antigens could be detected from leptotene--early zygotene until diplotene. The 190-kDa antigen appeared in a diffuse manner just before the appearance of the 30 + 33 kDa antigens. The 30 + 33 kDa antigens were not only detected in the axial elements of SCs but also in characteristic aggregates, which appeared in zygotene and persisted until after the SCs had disappeared. Such aggregates had rarely been observed in spermatocytes. The 125 kDa antigen was only present in the tripartite segments of SCs, at the inner edge of the lateral elements. Thus, the reaction of the Mab against the 125 kDa antigen was detectable in zygotene, pachytene, and very early diplotene. It appeared later than 30 + 33 kDa and 190 kDa antigens and it disappeared earlier. We found that several steps of the immunostaining procedure could cause variation in the intensity of the Mab reaction.

Cholesterol 26-hydroxylase activity of hamster liver mitochondria: isotope ratio analysis using deuterated 26-hydroxycholesterol

Deuterated 26-hydroxycholesterol prepared from diosgenin by modifications of existing methods permitted the determination of mitochondrial cholesterol 26-hydroxylase using endogenous cholesterol as the substrate. Enzyme activity in a group of Syrian hamsters was found to be 10.3 +/- 3.7 pmol.min-1.mg protein-1.

Metabolism of 3 beta-hydroxycholest-5-en-26-oic acid in hamsters

Metabolism of 26-hydroxycholesterol to 3 beta-hydroxychol-5-en-24-oic acid and other C24-bile acids has been expected to occur by way of 3 beta-hydroxycholest-5-en-26-oic acid in studies in vitro. 3 beta-Hydroxycholest-5-en-26-oic acid was infused intravenously into bile fistula hamsters and the following C24-bile acids were identified: 3 beta-hydroxychol-5-en-24-oic acid, lithocholic acid, chenodeoxycholic acid, and a small amount of cholic acid.

Bile acid synthesis in cell culture

Confluent cultures of Hep G2 cells were found to synthesize chenodeoxycholic and cholic acids continually. Chenodeoxycholic acid was synthesized at the rate of 58 +/- 8.6 micrograms/96 h, a rate more than 7-fold greater than that for cholic acid. Addition of 5 beta-cholestane-3 alpha, 7 alpha, 12 alpha-triol but not the -3 alpha, 7 alpha-diol was followed by an increase in cholic acid synthesis, thus indicating a relatively low 12 alpha-hydroxylase activity. Endogenous synthesis of monohydroxy bile acid ester sulfates was found, with maximum rates of 135 and 74 micrograms/96 h for lithocholic and 3 alpha-hydroxy-5-cholenoic acids, respectively. Incubation of Hep G2 cells in medium containing 25% D2O permitted a comparison of the precursor/product relationship of cholesterol with 3 beta-hydroxy-5-cholenoic acid. The pattern of incorporation of deuterium was in accordance with that expected, thus allowing the conclusion that this monohydroxy bile acid is derived from cholesterol and should be considered together with chenodeoxycholic and cholic acids as a primary bile acid.

Cholic acid synthesis from 26-hydroxycholesterol and 3-hydroxy-5-cholestenoic acid in the rabbit

Intravenous administration of 26-hydroxycholesterol to the rabbit with a bile fistula yielded cholic acid in proportions (84 and 86%) not significantly different from that derived from cholesterol. By contrast, the naturally occurring C27 bile acid 3 beta-hydroxy-5-cholestenoic acid yielded not more than 8% cholic acid. Thus initial 26-hydroxylation of cholesterol followed by 7-alpha-hydroxylation can provide sufficient amounts of cholic acid to be considered a quantitatively significant pathway for bile acid synthesis, and in addition it is the only pathway that can be the source of the circulating levels of C24 and C27 monohydroxy bile acids.

Bile acid synthesis: down-regulation by monohydroxy bile acids

The regulation of bile acid synthesis was studied in rabbits after interruption of the enterohepatic circulation by choledochoureteral anastomosis. Total daily bile acid output was 772 +/- 130 (SD) mumol/24 h, of which greater than 95% was glycocholic acid. Administration of deoxycholic or cholic acid or their conjugates (300-800 mumol) or gall-bladder bile failed to down-regulate endogenous bile acid synthesis. In contrast, chenodeoxycholic acid administration did down-regulate bile acid synthesis, but this effect was related to the formation and excretion of lithocholic acid. This observation was confirmed by the finding that i.v. infusion of 10-20 mumol of either lithocholic acid or 3 beta-hydroxy-5-cholenoic acid significantly reduced cholic acid synthesis. Thus monohydroxy bile acids, derived from either hepatic or intestinal sources, participate in the down-regulation of bile acid synthesis.

26-Hydroxycholesterol disulfate: metabolism and excretion in the normal neonate

Deuterated 26-hydroxycholesterol disulfate has been given in a tracer amount to neonates to evaluate the pool size, metabolism and excretion of the endogenously occurring compound in meconium. In a group of 5 normal neonates excretion of endogenous 26-hydroxycholesterol during the initial 72 h of life ranged from 327 to 1096 micrograms. Recovery of administered isotope during the same period was 66-98%. Only trace amounts of 26-hydroxycholesterol were recovered in urine. The findings indicate that relative to bile acid pool size, the normal neonate has a small intestinal pool of 26-hydroxycholesterol which, for the most part, is rapidly excreted and does not contribute significantly to bile acid synthesis. The techniques developed during the course of the study provide an approach to non invasive metabolic studies that give insights on the normal transition from fetal to neonatal life.

Bile acid synthesis. Metabolism of 3 beta-hydroxy-5-cholenoic acid to chenodeoxycholic acid

Metabolism of 3 beta-hydroxy-5-cholenoic acid to chenodeoxycholic acid has been found to occur in rabbits and humans, species that cannot 7 alpha-hydroxylate lithocholic acid. This novel pathway for chenodeoxycholic acid synthesis from 3 beta-hydroxy-5-cholenoic acid led to a reinvestigation of the pathway for chenodeoxycholic acid from 3 beta-hydroxy-5-cholenoic acid in the hamster. Simultaneous infusion of equimolar [1,2-3H]lithocholic acid and 3 beta-hydroxy-5-[14C]cholenoic acid indicated that the 14C enrichment of chenodeoxycholic acid was much greater than that of lithocholic acid. Thus, in all these species, a novel 7 alpha-hydroxylation pathway exists that prevents the deleterious biologic effects of 3 beta-hydroxy-5-cholenoic acid.

Bile acid synthesis in rat liver peroxisomes: metabolism of 26-hydroxycholesterol to 3 beta-hydroxy-5-cholenoic acid

Rat liver peroxisomes have been found to oxidize 26-hydroxycholesterol, the product of cholesterol C-26 hydroxylation to 3 beta-hydroxy-5-cholenoic acid. Peroxisomes were purified by differential and equilibrium density centrifugation in a steep linear metrizamide gradient to greater than 95% purity. Purity of peroxisomes was determined by measurement of specific marker enzymes. The activities of cytochrome oxidase (a mitochondrial marker) and acid phosphatase (a lysosomal marker) in the purified peroxisome fractions were below the level of detection. Esterase activity indicated a 2-4% microsomal contamination. Subsequent to incubation of peroxisomes with [16,22-3H]-26-hydroxycholesterol, the reaction products were extracted, methylated, acetylated, and subjected to thin-layer, high pressure liquid, and gas-liquid chromatographic analyses. 3 beta-Hydroxy-5-cholenoic acid was the major identifiable metabolite of 26-hydroxycholesterol. Incubations of pure microsomal fractions (greater than 99%) with 26-hydroxycholesterol under the same conditions demonstrated that the production of 3 beta-hydroxy-5-cholenoic acid by peroxisomes was not attributable to microsomal contamination. This study demonstrates that peroxisomes participate in the side-chain oxidation of intermediates in bile acid synthesis.

Rapid synthesis of 26-hydroxycholesterol from mevalonic acid in the Syrian hamster

Using isotope-ratio mass spectrometry, newly synthesized 26-hydroxycholesterol and its derivative, 3 beta-hydroxy-5-cholenoic acid, were detected in the liver and bile of animals within 2 h following intravenous administration of [5-13C]mevalonic acid. The findings indicate that 26-hydroxycholesterol merits further consideration as an in vivo modulator of HMG-CoA reductase activity.

Cerebrotendinous xanthomatosis: reduced serum 26-hydroxycholesterol

Serum 26-hydroxycholesterol was quantitated by isotope dilution-mass spectrometry in normal individuals and in patients with cerebrotendinous xanthomatosis. In the normal individuals, the concentration of 26-hydroxycholesterol in serum ranged from 4.3 to 13.0 microgram/100 ml. In five patients with CTX, 26-hydroxycholesterol in serum ranged from 0 to 0.6 microgram/100 ml. The findings can be explained by reduced or absent mitochondrial C27 steroid 26-hydroxylase activity. The method is useful for detection of CTX and perhaps other disturbances of sterol and bite acid metabolism.

Cholest-5-ene-3 beta, 26-diol: synthesis and biomedical use of a deuterated compound

To further studies of the metabolism of 26-hydroxycholesterol in fetal and neonatal life, a deuterated compound was prepared from kryptogenin by Clemmensen reduction. The spectra of the deuterated 26-hydroxycholesterol showed that five to nine deuterium atoms were incorporated per 26-hydroxycholesterol molecule, with the maximum incorporation of eight deuterium atoms. The deuterated compound was recovered unchanged from the feces of a child following oral administration. Comparison of the ratio of deuterated to protium compound indicated the presence of an endogenous pool of 26-hydroxycholesterol. Parenteral administration of the compound to a hamster indicated metabolism to deuterated chenodeoxycholic acid. The compound is useful as an isotope tracer for studies of the endogenous metabolism of 26-hydroxycholesterol.

26-Hydroxycholesterol. Identification and quantitation in human serum

Using isotope dilution mass spectrometry, 26-hydroxycholesterol was identified in the serum of normal adults. Total values ranged from 9.2 to 25.6 micrograms/100 ml of which 31-35% was free sterol. Density gradient ultracentrifugation indicates that the steroid is distributed among the low and high density lipoproteins.

Bile acid synthesis. Metabolism of 3 beta-hydroxy-5-cholenoic acid in the hamster

Synthesis of 3 beta-hydroxy-5-[1,2-3H]cholenoic acid has permitted a study of its metabolism in bile-fistula hamsters that received the compound by intravenous infusion. Metabolites in bile were identified by reverse isotope dilution after their complete resolution by high pressure liquid chromatography using muPorasil. Recovery of administered radioactivity ranged from 21-60% in three animals. In each study, lithocholic acid (0.8-4.4%) and chenodeoxycholic acid (7.8-11.3%) were identified as metabolites of 3 beta-hydroxy-5-cholenoate and can be considered primary bile acids in the side-chain pathway of bile acid synthesis beginning with the oxidation of cholesterol to 26-hydroxycholesterol.

Gas-liquid chromatography of bile acids: a new liquid phase for both acetate and trimethylsilyl derivatives

Polymetaphenoxylene (PPE-20) has been found to be more useful than cyclohexane dimethanol succinate (HI-EFF-8-BP) for trimethylsilyl derivatives of bile acids and to be preferable to trifluoropropyl substituted silicone (OV-210, QF-1) for analysis of their acetate derivatives.

Bile acid synthesis in man: metabolism of 7 -hydroxycholesterol- 14 C and 26-hydroxycholesterol- 3 H

The pathways of bile acid synthesis in man were evaluated by studying the metabolism of 7alpha-hydroxycholesterol-4-(14)C and 26-hydroxycholesterol-16, 22-(3)H administered parenterally to individuals requiring external biliary drainage. Techniques for the identification of metabolites were thin-layer chromatography, column chromatography, gas-liquid chromatography with stream splitting, and crystallization to constant specific activity. It was found that both compounds were rapidly metabolized to bile acids and excreted in bile. Of the total radioactivity recovered in bile as bile acids, 87% of the 26-hydroxycholesterol-(3)H and 90% of the 7alpha-hydroxycholesterol-(14)C was found to be metabolized to both chenodeoxycholate and cholate. Compared to 7alpha-hydroxycholesterol, a greater proportion of 26-hydroxycholesterol was found to be metabolized to chenodeoxycholate. These findings indicate that both 7alpha-hydroxycholesterol and 26-hydroxycholesterol can be intermediates in the metabolism of cholesterol to bile acids in man. The observation that conversion to cholate takes place less readily after C-26 hydroxylation is consistent with previous findings in other species.