Windows into spatial cognition: Mechanisms by which gesture-based instruction improve anatomy learning.

The ability to create efficient "mental models" or representations of anatomical structures is crucial for achieving competence in most areas of anatomy. Gesture-based teaching has been recognized to lighten cognitive loads and allow superior mental model creation compared to non-gestural teaching practices. This commentary explores the cognitive basis and possible mechanisms behind this advantage such as (1) reducing visual working memory load, (2) allowing parallel and sequential development of internal representations, and (3) facilitating preferential feature extraction and improved organization of spatial information. We also highlight how information transfer limitations of the gestural medium, interestingly, unveil features and organizational motifs preserved in the "expert's" mental schemas concerning particular anatomical structures. The universal and innate use of gestures in communication, their visual nature, and the ability to break down complex spatial information through sequential steps, all add to the immense potential of this subtle yet powerful tool of hand gestures. As pedagogical practices in the anatomical sciences continue to evolve largely towards technology-enhanced teaching utilizing perceptually richer media, the unique advantages of gesture-based teaching need to be reemphasized.

Teaching Cellular Architecture: The Global Status of Histology Education.

Histology or microanatomy is the science of the structure and function of tissues and organs in metazoic organisms at the cellular level. By definition, histology is dependent on a variety of microscope techniques, usually light or more recently virtual, as well as electron microscopy. Since its inception more than two centuries ago, histology has been an integral component of biomedical education, specifically for medical, dental, and veterinary students. Traditionally, histology has been taught in two sequential phases, first a didactic transfer of information to learners and secondly a laboratory segment in which students develop the skill of analyzing micrographic images. In this chapter, the authors provide an overview of how histology is currently taught in different global regions. This overview also outlines which educational strategies and technologies are used, and how the local and cultural environment influences the histology education of medical and other students in different countries and continents. Also discussed are current trends that change the teaching of this basic science subject.

Virtual Microscopy Goes Global: The Images Are Virtual and the Problems Are Real.

For the last two centuries, the scholarly education of histology and pathology has been based on technology, initially on the availability of low-cost, high-quality light microscopes, and more recently on the introduction of computers and e-learning approaches to biomedical education. Consequently, virtual microscopy (VM) is replacing glass slides and the traditional light microscope as the main instruments of instruction in histology and pathology laboratories. However, as with most educational changes, there are advantages and disadvantages associated with a new technology. The use of VM for the teaching of histology and pathology requires an extensive infrastructure and the availability of computing devices to all learners, both posing a considerable financial strain on schools and students. Furthermore, there may be valid reasons for practicing healthcare professionals to maintain competency in using light microscopes. In addition, some educators may be reluctant to embrace new technologies. These are some of the reasons why the introduction of VM as an integral part of histology and pathology instruction has been globally uneven. This paper compares the teaching of histology and pathology using traditional or VM in five different countries and their adjacent regions, representing developed, as well as developing areas of the globe. We identify general and local roadblocks to the introduction of this still-emerging didactic technology and outline solutions for overcoming these barriers.

"Air Anatomy" - Teaching Complex Spatial Anatomy Using Simple Hand Gestures.

Spatial understanding of complex anatomical concepts is often a challenge for learners, as well as for educators. It is even more challenging for students with low mental spatial abilities. There are many options to teach spatial relationships, ranging from simple models to high-end three-dimensional (3D) virtual reality tools. Using a randomized controlled trial design, this study explored the use of a unique combination of deictic and iconic hand gestures to enhance spatial anatomical understanding, coining the term "Air Anatomy". The control group (n = 45) was given a lecture on the anatomy of extraocular muscles, while the intervention group (n = 49) received the same lecture including "Air Anatomy" hand gestures. When compared to the control group, the post-test scores for the intervention group were significantly higher for basic recall (P < 0.001; Mann-Whitney U test) and for the application of knowledge (P = 0.015; Mann-Whitney U test). Students with low to moderate spatial ability (as assessed by a mental rotation test) were found to benefit most by this technique. Students in the intervention group also reported a lower extrinsic cognitive load and higher germane load, when compared to the control group. An instructional skills questionnaire survey indicated the effectiveness of this technique in improving overall classroom experience. Feedback of the students in the intervention group was also favorable for instruction using "Air Anatomy". The study suggests that "Air Anatomy" is a useful, "no-cost", accessible method that aids spatial understanding of anatomical concepts.

Overcoming Barriers in a Traditional Medical Education System by the Stepwise, Evidence-Based Introduction of a Modern Learning Technology.

INTRODUCTION: Histology teaching in India and in other developing countries has not changed much over the past decades and has not joined the global movement of using virtual microscopy (VM). Many factors may have contributed to this academic inertia-including curricular requirements for traditional microscopy (TM) skills, assessments that are heavily based on TM, and unfamiliarity with modern technology among faculty, as well as infrastructural shortcomings. This study is aimed at overcoming these roadblocks by using a blended approach combining VM with TM in a tradition-centered curricular setting. METHODS: For validation of this approach, the authors conducted a non-randomized controlled trial with a crossover design on first year medical students at the Government Medical College, Thiruvananthapuram, India. Examination scores and responses of a student group taught with VM as an adjunct to TM were compared with a student group taught with TM only. RESULTS: The test group had significantly better results when compared to the control group for knowledge-based tests (p = 0.012; analysis of co-variance) and for an unannounced visual-based test conducted 1 month later (p = 0.001; Mann-Whitney U test). Feedback collected from students showed highly favorable responses to the use of VM for teaching histology. CONCLUSION: This study should encourage Indian medical colleges and schools in other developing countries to start using VM as a supplementary approach for their histology education programs. Furthermore, as the Medical Council of India recommends the introduction of new competency-based integrated curriculum in India starting in 2019, the use of VM may facilitate more effective learning in the new scenario. TRIAL REGISTRATION: CTRI/2018/04/012928.

An unusual origin and course of the thyroidea ima artery, with absence of inferior thyroid artery bilaterally.

We report an unusual origin and course of the thyroidea ima artery in a male cadaver. The ima artery originated from the right subclavian artery very close to origin of the right vertebral artery. The artery coursed anteriorly between the common carotid artery medially and internal jugular vein laterally. It then coursed obliquely, from below upwards, from lateral to medial superficial to common carotid artery, to reach the inferior pole of the right lobe of thyroid and branched repeatedly to supply the anteroinferior and posteroinferior aspects of both the thyroid lobes and isthmus. The superior thyroid arteries were normal. Both the inferior thyroid arteries were absent. The unusual feature of this thyroidea ima artery is its origin from the subclavian artery close to vertebral artery origin, the location being remarkably far-off from the usual near midline position, and the oblique and relatively superficial course. This report is a caveat to neck surgeons to consider such a superficially running vessel to be a thyroidea ima artery.

Can Chaotic Analysis of Electroencephalogram Aid the Diagnosis of Encephalopathy?

Chaotic analysis is a relatively novel area in the study of physiological signals. Chaotic features of electroencephalogram have been analyzed in various disease states like epilepsy, Alzheimer's disease, sleep disorders, and depression. All these diseases have primary involvement of the brain. Our study examines the chaotic parameters in metabolic encephalopathy, where the brain functions are involved secondary to a metabolic disturbance. Our analysis clearly showed significant lower values for chaotic parameters, correlation dimension, and largest Lyapunov exponent for EEG in patients with metabolic encephalopathy compared to normal EEG. The chaotic features of EEG have been shown in previous studies to be an indicator of the complexity of brain dynamics. The smaller values of chaotic features for encephalopathy suggest that normal complexity of brain function is reduced in encephalopathy. To the best knowledge of the authors, no similar work has been reported on metabolic encephalopathy. This finding may be useful to understand the neurobiological phenomena in encephalopathy. These chaotic features are then utilized as feature sets for Support Vector Machine classifier to identify cases of encephalopathy from normal healthy subjects yielding high values of accuracy. Thus, we infer that chaotic measures are EEG parameters sensitive to functional alterations of the brain, caused by encephalopathy.

Can the angle between optic nerves indicate whether optic chiasm is prefixed, normofixed or postfixed? An anatomical study with radiologic and neurosurgical implications.

PURPOSE: The objective of this study was to measure the angle (Interneural angle, INA) between intracranial segments of optic nerves (ISON), and to look for any relation between it and the relative anteroposterior location (RAPL) of the optic chiasm (OC)-viz. prefixed, normofixed and postfixed. METHODS: The sample comprised of 100 autopsy specimens from South Indian population. INA was measured using software-aided processing of digital photographs. Length of the ISON was measured on each side using Vernier calipers. RAPL of the OC was noted during dissection. These were analysed with statistical methods. RESULTS: RAPL of OC was found to be prefixed in 24 %, normofixed in 65 % and postfixed in 11 %. The INA had an overall mean of 69.9° (SD 9.29°). ANOVA confirmed statistically significant difference in INA among different groups; the corresponding mean value for the group was as follows: 79.61° (prefixed), 68.10° (normofixed) and 59.48° (postfixed). ROC curve was plotted for the use of various 'cut off' values of INA to 'diagnose' prefixed OC; an INA ≥71.4° was seen to diagnostically correlate with prefixed OC with 83.3 % sensitivity and 75 % specificity. CONCLUSIONS: The INA is wider when OC is prefixed, intermediate when normofixed and narrowed when postfixed. This observation throws light on the possibility of using INA as a marker of RAPL of OC. As INA can be measured in axial MRI sections, it can be used in differentiation of the cases with prefixed OC from others during pre-operative work up for pituitary surgeries and to identify individuals 'at risk' during subfrontal approach for pituitary lesions.

A Morphometric Study of the Foramen of Diaphragma Sellae and Delineation of Its Relation to Optic Neural Pathways through Computer Aided Superimposition.

The diaphragma sellae (DS) is a fold of dura that forms a partial roof over the pituitary gland. The foramen of the diaphragma sellae (FDS) is thereby a pathway for suprasellar extension of pituitary tumors. The purpose of this study was to describe the anatomical dimensions of the DS and FDS and to understand the relationship of FDS with the overlying optic chiasma. The study was conducted in 100 autopsy cases. Measurements were taken using vernier calipers. Photographs, taken before and after removal of optic pathway, were superimposed using image processing software. The results showed that the mean A-P dimension of DS was 1.17 ± 0.48 cm; the lateral dimension of DS was 1.58 ± 0.60 cm. The mean A-P dimension of FDS was 0.66 ± 0.42 cm; the lateral dimension of FDS was 0.82 cm ± 0.54 cm. The shapes of FDS were irregular (40%), transversely oval (29%), circular (13%), sagittally oval (11%), or trapezoid with posterior dimension more than the anterior one (6%) or anterior dimension more than the posterior one (1%). The margins of FDS were either well defined (31%) or ill defined (69%). The positional relation of FDS to optic chiasma was also found out.