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Objectives: Visual expertise is essential for image-based tasks that rely on visual cues, such as in radiology or histology. Studies suggest that eye movements are related to visual expertise and can be measured by near-infrared eye-tracking. With the popularity of device-embedded webcam eye-tracking technology, cost-effective use in educational contexts has recently become amenable. This study investigated the feasibility of such methodology in a curricular online-only histology course during the 2021 summer term.Methods: At two timepoints (t1 and t2), third-semester medical students were asked to diagnose a series of histological slides while their eye movements were recorded. Students’ eye metrics, performance and behavioral measures were analyzed using variance analyses and multiple regression models.Results: First, webcam-eye tracking provided eye movement data with satisfactory quality (=115.7 px±31.1). Second, the eye movement metrics reflected the students’ proficiency in finding relevant image sections (=6.96±1.56 vs. irrelevant areas=4.50±1.25). Third, students’ eye movement metrics successfully predicted their performance (R=0.39, p

Sex and gender bias in anatomy learning materials are considered a "hidden obstacle" to gender equity in medical curricula. The purpose of this study was to investigate whether quantitative sex and gender biases do exist in popular anatomy e-learning platforms and compare the results with those found in contemporary textbooks and atlases. A systematic content-analysis was performed on N = 3767 images published from 2008 to 2021 in which sex/gender could be identified by considering technical aspects of illustration and various intersectional categories. E-learning platforms took into account an appropriate representation of the female body and presented even more females (n = 932/1412; 66%), more frequently from a ventral/anterior (X[superscript 2] = 26, P < 0.001) and whole-body perspective (X[superscript 2] = 27, P < 0.001). This was in contrast to German anatomy books, where the results pointed to a significant sex and gender bias. For example, all books assessed underrepresented females (n = 707/2355; 30%) and placed them in stereotypical sex-specific context (X[superscript 2] = 348, P < 0.001), showing them more often from a caudal/inferior (X[superscript 2] = 99, P < 0.001) and internal (X[superscript 2] = 132, P < 0.001) perspective. Altogether, the visual representation of sex and gender in anatomical curricula is still biased and the stereotypical perceptions of human anatomy seem to be a global issue. However, the increasing use of electronic learning platforms, which gradually replace traditional books is changing the way the male and female body is depicted, which might offer new opportunities for reducing stereotypes in anatomy education.

The various psychological dimensions of professional identity formation (PIF) are an important aspect of the study course for undergraduate medical students. Anatomical learning environments have been repeatedly shown to play a critical role in forming such an identity; however, relevance of PIF during sonoanatomical training remains underexplored. At the end of their basic anatomy studies, third-semester medical students took part in a four-day block course on anatomy and imaging. Anatomical content was revised in small groups using peer teaching and imaging methods, including one hour of hands-on sonoanatomy sessions each day. On-site sonoanatomy was identified as an excellent format to support students' transition from the pre-clinical to clinical phase as medical experts-to-be. Students enjoyed practical exercises and the clinical input, which increased their interest in the medical profession and their academic studies. This study further examined the effects of the transition into an online-only format, necessitated by the current Covid-19 pandemic. A comparison was made between the quantitative and qualitative evaluation data, and the written results of examinations of several on-site (n = 1096, "mean age" = 22.4 years ± 2.18), and online-only cohorts (n = 230, "mean age" = 22.6 years ± 2.21). The online-only transition led to a reduction of all PIF-related variables measured, losing identity-related variables, increasing students' stress levels, and reducing their long-term academic performance. Together, this study demonstrates presence of PIF in undergraduate sonoanatomy teaching, and cautions against the uncritical online-only substitution of hands-on learning environments.

Background: Students within a cohort might employ unique subsets of learning strategies (LS) to study. However, little research has aimed to elucidate subgroup‐specific LS usage among medical students. Recent methodological developments, particularly person‐centred approaches such as latent profile analysis (LPA), offer ways to identify relevant subgroups with dissimilar patterns of LS use. In this paper, we apply LPA to explore subgroups of medical students during preclinical training in anatomy and examine how these patterns are linked with learning outcomes. Methods: We analysed the LS used by 689 undergraduate, 1st and 2nd‐year medical students across 6 German universities who completed the short version of the Learning Strategies of University Students (LIST‐K) questionnaire, and answered questions towards external criteria such as learning resources and performance. We used the thirteen different LS facets of the LIST‐K (four cognitive, three metacognitive, three management of internal and three management of external resources) as LPA indicators. Results: Based on LPA, students can be grouped into four distinct learning profiles: Active learners (45% of the cohort), collaborative learners (17%), structured learners (29%) and passive learners (9%). Students in each of those latent profiles combine the 13 LS facets in a unique way to study anatomy. The profiles differ in both, the overall level of LS usage, and unique combinations of LS used for learning. Importantly, we find that the facets of LS show heterogeneous and subgroup‐specific correlations with relevant outcome criteria, which partly overlap but mostly diverge from effects observed on the population level. Conclusions: The effects observed by LPA expand results from variable‐centered efforts and challenge the notion that LS operate on a linear continuum. These results highlight the heterogeneity between subgroups of learners and help generate a more nuanced interpretation of learning behaviour. Lastly, our analysis offers practical implications for educators seeking to tailor learning experiences to meet individual student needs. Darici et al. explore medical students' learning strategies, identifying four distinct profiles that help to highlight how learning is rarely a linear journey. [ABSTRACT FROM AUTHOR]

Experts perceive and evaluate domain‐specific visual information with high accuracy. In doing so, they exhibit eye movements referred to as "expert gaze" to rapidly focus on task‐relevant areas. Using eye tracking, it is possible to record these implicit gaze patterns and present them to histology novice learners during training. This article presents a comprehensive evaluation of such expert gaze cueing on pattern recognition of medical students in histology. For this purpose, 53 students were randomized into two groups over eight histology sessions. The control group was presented with an instructional histology video featuring voice commentary. The gaze cueing group was presented the same video, but with an additional overlay of a live recording of the expert's eye movements. Afterward, students' pattern recognition was assessed through 20 image‐based tasks (5 retention, 15 transfer) and their cognitive load with the Paas scale. Results showed that gaze cueing significantly outperformed the control group (p = 0.007; d = 0.40). This effect was evident for both, retention (p = 0.003) and transfer tasks (p = 0.046), and generalized across different histological contexts. The cognitive load was similar in both groups. In conclusion, gaze cueing helps histology novice learners to develop their pattern recognition skills, offering a promising method for histology education. Histology educators could benefit from this instructional strategy to provide new forms of attentional guidance to learners in visually complex learning environments. [ABSTRACT FROM AUTHOR]

Paroxysmal nonkinesigenic dyskinesia (PNKD) is an autosomal dominant episodic movement disorder precipitated by coffee, alcohol, and stress. We previously identified the causative gene but the function of the encoded protein remains unknown. We also generated a PNKD mouse model that revealed dysregulated dopamine signaling in vivo. Here, we show that PNKD interacts with synaptic active zone proteins Rab3-interacting molecule (RIM)1 and RIM2, localizes to synapses, and modulates neurotransmitter release. Overexpressed PNKD protein suppresses release, and mutant PNKD protein is less effective than wild-type at inhibiting exocytosis. In PNKD KO mice, RIM1/2 protein levels are reduced and synaptic strength is impaired. Thus, PNKD is a novel synaptic protein with a regulatory role in neurotransmitter release.

Presynaptic Ca2+ influx through voltage-gated Ca2+ channels (VGCCs) is a key signal for synaptic vesicle release. Synaptic neurexins can partially determine the strength of transmission by regulating VGCCs. However, it is unknown whether neurexins modulate Ca2+ influx via all VGCC subtypes similarly. Here, we performed live cell imaging of synaptic boutons from primary hippocampal neurons with a Ca2+ indicator. We used the expression of inactive and active Cre recombinase to compare control to conditional knockout neurons lacking either all or selected neurexin variants. We found that reduced total presynaptic Ca2+ transients caused by the deletion of all neurexins were primarily due to the reduced contribution of P/Q-type VGCCs. The deletion of neurexin1α alone also reduced the total presynaptic Ca2+ influx but increased Ca2+ influx via N-type VGCCs. Moreover, we tested whether the decrease in Ca2+ influx induced by activation of cannabinoid receptor 1 (CB1-receptor) is modulated by neurexins. Unlike earlier observations emphasizing a role for β-neurexins, we found that the decrease in presynaptic Ca2+ transients induced by CB1-receptor activation depended more strongly on the presence of α-neurexins in hippocampal neurons. Together, our results suggest that neurexins have unique roles in the modulation of presynaptic Ca2+ influx through VGCC subtypes and that different neurexin variants may affect specific VGCCs. [ABSTRACT FROM AUTHOR]

All anatomical educators hope that students apply past training to both similar and new tasks. This two‐group longitudinal study investigated the development of such transfer of learning in a histology course. After 0, 10, and 20 sessions of the 10‐week‐long course, medical students completed theoretical tasks, examined histological slides trained in the course (retention task), and unfamiliar histological slides (transfer task). The results showed that students in the histology group gradually outperformed the control group in all tasks, especially in the second half of the course, η2 = 0.268 (p < 0.001). The best predictor of final transfer performance was students' retention performance after 10 sessions, β = 0.32 (p = 0.028), and theoretical knowledge after 20 sessions, β = 0.46 (p = 0.003). Results of eye tracking methodology further revealed that the histology group engaged in greater "visual activity" when solving transfer tasks, as indicated by an increase in the total fixation count, η2 = 0.103 (p = 0.014). This longitudinal study provides evidence that medical students can use what they learn in histology courses to solve unfamiliar problems but cautions that positive transfer effects develop relatively late in the course. Thus, course time and the complex relationship between theory, retention, and transfer holds critical implications for anatomical curricula seeking to foster the transfer of learning. [ABSTRACT FROM AUTHOR]

The α2δ auxiliary subunits of voltage-gated calcium channels (VGCC) were traditionally regarded as modulators of biophysical channel properties. In recent years, channel-independent functions of these subunits, such as involvement in synapse formation, have been identified. In the central nervous system, α2δ isoforms 1, 2, and 3 are strongly expressed, regulating glutamatergic synapse formation by a presynaptic mechanism. Although the α2δ-4 isoform is predominantly found in the retina with very little expression in the brain, it was recently linked to brain functions. In contrast, Cachd1, a novel α2δ-like protein, shows strong expression in brain, but its function in neurons is not yet known. Therefore, we aimed to investigate the presynaptic functions of α2δ-4 and Cachd1 by expressing individual proteins in cultured hippocampal neurons. Both α2δ-4 and Cachd1 are expressed in the presynaptic membrane and could rescue a severe synaptic defect present in triple knockout/knockdown neurons that lacked the α2δ-1-3 isoforms (α2δ TKO/KD). This observation suggests that presynaptic localization and the regulation of synapse formation in glutamatergic neurons is a general feature of α2δ proteins. In contrast to this redundant presynaptic function, α2δ-4 and Cachd1 differentially regulate the abundance of presynaptic calcium channels and the amplitude of presynaptic calcium transients. These functional differences may be caused by subtle isoform-specific differences in α1-α2δ protein–protein interactions, as revealed by structural homology modelling. Taken together, our study identifies both α2δ-4 and Cachd1 as presynaptic regulators of synapse formation, differentiation, and calcium channel functions that can at least partially compensate for the loss of α2δ-1-3. Moreover, we show that regulating glutamatergic synapse formation and differentiation is a critical and surprisingly redundant function of α2δ and Cachd1. [ABSTRACT FROM AUTHOR]

[alpha]-Neurexins are neuron-specific cell-surface molecules that are essential for the functional organization of presynaptic [Ca.sup.2+] channels and release sites. We have now examined postsynaptic glutamate receptor function in [alpha]-neurexin knockout (KO) mice by using whole-cell recordings in cultured neocortical slices. Unexpectedly, we find that [alpha]-neurexins are required for normal activity of N-methyl-D-aspartate (NMDA)- but not [alpha]-amino-3-hydroxy-5-methyl-4-isoxyzolepropionic acid (AMPA)-type glutamate receptors. In [alpha]-neurexin-deficient mice, the ratio of NMDA- to AMPA-receptor currents, recorded as evoked synaptic responses, was diminished [approximately equal to] 50%. Furthermore, the NMDA-receptor-dependent component of spontaneous synaptic miniature responses was reduced [approximately equal to] 50%, whereas the AMPA-receptor-dependent component was unaffected. No alterations in the levels of NMDA- or AMPA-receptor proteins were detected. These results suggest that [alpha]-neurexins are required to maintain normal postsynaptic NMDA-receptor function. The decrease in NMDA-receptor activity in [alpha]-neurexin-deficient synapses could be due to a transsynaptic effect on the postsynaptic neuron (i.e., [alpha]-neurexins on the presynaptic inputs guide postsynaptic NMDA-receptor function) or to a cell-autonomous postsynaptic effect of [alpha]-neurexins on NMDA-receptor activity. To distinguish between these two possibilities, we cocultured WT GFP-labeled neurons with neocortical slices from [alpha]-neurexin-deficient or control mice. No difference was found between WT neurons innervated by inputs that contained or lacked [alpha]-neurexins, indicating that the absence of presynaptic [alpha]-neurexins alone does not depress postsynaptic NMDA-receptor function. Our data suggest that, in addition to the previously described presynaptic impairments, loss of [alpha]-neurexins induces postsynaptic changes by a cell-autonomous mechanism.

Author(s): Markus Missler (corresponding author) [1, 2, 3]; Weiqi Zhang [3]; Astrid Rohlmann [3]; Gunnar Kattenstroth [4]; Robert E. Hammer [2, 5]; Kurt Gottmann [4]; Thomas C. Südhof (corresponding author) [...]