Neuroanatomy Learning: Augmented Reality vs. Cross-Sections.

Neuroanatomy education is a challenging field which could benefit from modern innovations, such as augmented reality (AR) applications. This study investigates the differences on test scores, cognitive load, and motivation after neuroanatomy learning using AR applications or using cross-sections of the brain. Prior to two practical assignments, a pretest (extended matching questions, double-choice questions and a test on cross-sectional anatomy) and a mental rotation test (MRT) were completed. Sex and MRT scores were used to stratify students over the two groups. The two practical assignments were designed to study (1) general brain anatomy and (2) subcortical structures. Subsequently, participants completed a posttest similar to the pretest and a motivational questionnaire. Finally, a focus group interview was conducted to appraise participants' perceptions. Medical and biomedical students (n = 31); 19 males (61.3%) and 12 females (38.7%), mean age 19.2 ± 1.7 years participated in this experiment. Students who worked with cross-sections (n = 16) showed significantly more improvement on test scores than students who worked with GreyMapp-AR (P = 0.035) (n = 15). Further analysis showed that this difference was primarily caused by significant improvement on the cross-sectional questions. Students in the cross-section group, moreover, experienced a significantly higher germane (P = 0.009) and extraneous cognitive load (P = 0.016) than students in the GreyMapp-AR group. No significant differences were found in motivational scores. To conclude, this study suggests that AR applications can play a role in future anatomy education as an add-on educational tool, especially in learning three-dimensional relations of anatomical structures.

The Effect of Passive and Active Education Methods Applied in Repetition Activities on the Retention of Anatomical Knowledge.

This study examines the long-term retention of anatomical knowledge from 180 students after various repetition activities. The retention of anatomical knowledge was assessed by multiple-choice tests at five different points in time: before and after a course in Functional Anatomy, before and after repetition activities that occurred 14 weeks after this course, and 28 weeks after this course to establish long-term retention. Students were divided into five groups: one without any repetition activity, one with a restricted repetition activity (the multiple-choice test), and three groups that were offered repetition activities (traditional lecture, e-learning module, and small group work in the dissection room). During all three repetition activities the same information was conveyed, and this content was not revisited in other courses for the duration of the study. The results showed that students who did not engage in a repetition activity scored significantly lower on the long-term retention test compared to all other groups (ANCOVA: P = 0.0001). Pair-wise comparison with estimated means showed that the other four groups, regardless of the type of repeating activity, did not differ in the amount of knowledge they retained during any of the five assessments (P = 0.008, P = 0.0001, P = 0.001, and P = 0.0001, respectively). This study suggests that the type of repetition activity has no effect on knowledge retention both immediately following the activity and in the long term. It is concluded that the repetition of anatomical knowledge in any form is beneficial for students and will likely improve student outcomes in a curriculum that builds on prior knowledge.

Inducing targeted failure in cadaveric testing of 3-segment spinal units with and without simulated metastases.

We propose an experimental setup and protocol able to induce targeted failure of the middle vertebra in 3-segment spinal units and to capture the specimens' deformation in their post-failure state. Sixteen 3-segment spinal units with and without artificial metastases were destructively tested in axial compression using one of two failure criteria; either: (A) A clear drop in force (>10-15% of peak force) (n = 4); or (B) A minimum displacement of 5 mm (n = 12). Subsequently, the specimens were fully fixated in polymethylmethacrylate (PMMA), thereby preserving their post-failure state. Pre- and post-experiment computed tomography (CT) scans were acquired to determine the occurrence of failure in one of the vertebral bodies. All specimens were successfully fixated in their post-failure state. When applying failure criterion A, two specimens showed signs of failure. When applying failure criterion B, all specimens showed signs of failure; in 9 out of 12 specimens this occurred in the middle vertebrae only. In conclusion, this research provides an experimental setup and protocol able to induce targeted failure of 3-segment spinal units and to capture the specimens' deformation in their post-failure state. Furthermore, this study illustrates the importance of an adequate failure criterion for successful simulation of vertebral fractures in an experimental setup.

Collateral artery pathways of the femoral and popliteal artery.

BACKGROUND: The role of collateral artery circulation in the lower limb is under debate but clinically relevant, particularly when using covered stents for occlusive disease. Covered stents seem to outperform nitinol stents in extensive disease, but collaterals could be essential in case of acute thrombosis. In the present study, we describe the collateral pathways of the deep and superficial femoral artery (DFA, SFA) and the popliteal artery (PA), observed in human cadavers. METHODS: Ten fresh frozen cadaver legs were selected. The SFA and DFA were separately cannulated and injected with a different colored latex mixture simultaneously. After curing of the latex, the circulation was dissected thus visualizing the main arteries and their collateral vessels. The process was photographed and recorded, and collateral pathways were analyzed using a standardized vessel segmentation. The upper leg was divided in three regions, that is, the femoral triangle (F), the adductor canal (H), and the popliteal fossa (P) that, in turn, were split in three segments (1, 2, and 3, from proximal to distal). RESULTS: Overall, 113 collateral vessels were found; 69 originated from the DFA, 34 from the SFA, and 10 from the PA. The majority of collaterals originating from the DFA terminated in the SFA (57%). Fifty-six of 113 collaterals (50%) ended in either the distal adductor channel (H3) or the proximal PA (P1). Another 28 collateral arteries (25%) had their origin in this segment (H3, P1) and mostly connected to the P2 and P3 segments. Forty-three collaterals of the DFA and H3 segment had a direct or indirect connection to below the knee muscles. CONCLUSIONS: The majority of collaterals originate from the DFA, and the greater part of all collaterals has a connection with the H3-P1 segment. This observation may have clinical implications in the planning of endovascular procedures.

Longitudinal retention of anatomical knowledge in second-year medical students.

The Radboud University Medical Center has a problem-based, learner-oriented, horizontally, and vertically integrated medical curriculum. Anatomists and clinicians have noticed students' decreasing anatomical knowledge and the disability to apply knowledge in diagnostic reasoning and problem solving. In a longitudinal cohort, the retention of anatomical knowledge gained during the first year of medical school among second-year medical students was assessed. In May 2011, 346 medical students applied for the second-year gastro-intestinal (GI) tract course. The students were asked to participate in a reexamination of a selection of anatomical questions of an examination from October 2009. The examination consisted of a clinical anatomy case scenario and two computed tomography (CT) images of thorax and abdomen in an extended matching format. A total of 165 students were included for analysis. In 2011, students scored significantly lower for the anatomy examination compared to 2009 with a decline in overall examination score of 14.7% (±11.7%). Decrease in knowledge was higher in the radiological questions, compared to the clinical anatomy cases 17.5% (±13.6%) vs. 7.9% (±10.0%), respectively, d = 5.17. In both years, male students scored slightly better compared to female students, and decline of knowledge seems somewhat lower in male students (13.1% (±11.1%) vs. 15.5% (±12.0%), respectively), d = -0.21. Anatomical knowledge in the problem-oriented horizontal and vertical integrated medical curriculum, declined by approximately 15% 1.5 year after the initial anatomy course. The loss of knowledge in the present study is relative small compared to previous studies. Anat Sci Educ 10: 242-248. © 2016 American Association of Anatomists.

Actual drawing of histological images improves knowledge retention.

Medical students have to process a large amount of information during the first years of their study, which has to be retained over long periods of nonuse. Therefore, it would be beneficial when knowledge is gained in a way that promotes long-term retention. Paper-and-pencil drawings for the uptake of form-function relationships of basic tissues has been a teaching tool for a long time, but now seems to be redundant with virtual microscopy on computer-screens and printers everywhere. Several studies claimed that, apart from learning from pictures, actual drawing of images significantly improved knowledge retention. However, these studies applied only immediate post-tests. We investigated the effects of actual drawing of histological images, using randomized cross-over design and different retention periods. The first part of the study concerned esophageal and tracheal epithelium, with 384 medical and biomedical sciences students randomly assigned to either the drawing or the nondrawing group. For the second part of the study, concerning heart muscle cells, students from the previous drawing group were now assigned to the nondrawing group and vice versa. One, four, and six weeks after the experimental intervention, the students were given a free recall test and a questionnaire or drawing exercise, to determine the amount of knowledge retention. The data from this study showed that knowledge retention was significantly improved in the drawing groups compared with the nondrawing groups, even after four or six weeks. This suggests that actual drawing of histological images can be used as a tool to improve long-term knowledge retention.

An investigation of anatomical competence in junior medical doctors.

Because of a decrease of the time available for anatomy education, decisions need to be made to reduce the relevant content of the anatomy curriculum. Several expert consensus initiatives resulted in lists of structures, lacking analysis of anatomical competence. This study aims to explore the use of anatomical knowledge by medical doctors in an attempt to delineate the nature of anatomical competence. The research question is: what kind of anatomical knowledge do junior medical doctors use during a consultation with a patient presenting with a shoulder complaint? Ten junior medical doctors participated in this stimulated recall study. Each of them was videotaped while performing a consultation with a standardized patient with a complex shoulder complaint. The recording was viewed immediately after. Participants were videotaped again while verbalizing the thoughts they remembered having during the consultation. Verbatim transcriptions were coded by two coders using the qualitative data analysis ATLAS.ti software. Results were that these junior medical doctors used anatomical knowledge in all phases of the consultation, especially during physical examination. The use of anatomical terms was strongly associated with clinical reasoning and it was apparent that every subject visualized relevant anatomical information. Conclusion is that young medical doctors actively use their anatomical knowledge and it seems that the relevant anatomy consists largely of adequate visual representations in memory. Anatomy teachers should focus the students' learning activity on building an adequate visual representation of anatomical structures. This should be supported by assessments that test the quality of the students' visual representations.

Effects of learning content in context on knowledge acquisition and recall: a pretest-posttest control group design.

BACKGROUND: It is generally assumed that learning in context increases performance. This study investigates the relationship between the characteristics of a paper-patient context (relevance and familiarity), the mechanisms through which the cognitive dimension of context could improve learning (activation of prior knowledge, elaboration and increasing retrieval cues), and test performance. METHODS: A total of 145 medical students completed a pretest of 40 questions, of which half were with a patient vignette. One week later, they studied musculoskeletal anatomy in the dissection room without a paper-patient context (control group) or with (ir)relevant-(un)familiar context (experimental groups), and completed a cognitive load scale. Following a short delay, the students completed a posttest. RESULTS: Surprisingly, our results show that students who studied in context did not perform better than students who studied without context. This finding may be explained by an interaction of the participants' expertise level, the nature of anatomical knowledge and students' approaches to learning. A relevant-familiar context only reduced the negative effect of learning the content in context. Our results suggest discouraging the introduction of an uncommon disease to illustrate a basic science concept. Higher self-perceived learning scores predict higher performance. Interestingly, students performed significantly better on the questions with context in both tests, possibly due to a 'framing effect'. CONCLUSIONS: Since studies focusing on the physical and affective dimensions of context have also failed to find a positive influence of learning in a clinically relevant context, further research seems necessary to refine our theories around the role of context in learning.

What is more effective: a daily or a weekly formative test?

BACKGROUND: Exams in anatomy courses are traditionally summative. Formative testing induces retrieval practice, provides feedback and enhances learning results. We investigated the optimal frequency for retrieval practice during an anatomy course. METHOD: During a first-year course, students were offered four online daily quizzes a week that assessed thoracic anatomy. Once a week they received a quiz about abdominal anatomy. Students immediately received feedback afterwards. In the fourth course week, a survey about participation and satisfaction was taken. 424 students participated in the final summative exam. Trunk wall questions were used as a control. Relationship between participation and test results was investigated with a one-way ANOVA. RESULTS: More frequent participation in formative tests was correlated to higher scores in the summative exam with no difference between daily and weekly quizzes. This effect was found for thorax-abdomen and 'control' trunk wall questions. Participation in weekly quizzes was higher (p < 0.001). All survey responses showed a significant difference in favour of the weekly quiz (p < 0.001). DISCUSSION AND CONCLUSION: Participation in formative quizzes was correlated to summative exam scores. This correlation was not specific for the material tested, probably because of diligence. Student participation and preference were much higher in weekly quizzes.

Lateral lower leg perforator flaps: an anatomical study to localize and classify lateral lower leg perforators.

Despite increasing use of lateral lower leg perforator flaps, comprehensive anatomical data are still lacking. The aim of this article was to comprehensively document the pattern of usable lateral lower leg perforators. Systematic mapping of 16 cadaver leg perforators in a well-defined area was performed to elucidate location, course, length, diameter, and origin. Overall, 197 perforators were found in 16 lateral lower legs. The mean number of perforators per leg with a diameter ≥ 0.3 mm was 13.4 ± 3.6. Most perforators were found in the distal third (39.0%), followed by the middle third (32.0%), and proximal third (29.0%). A musculocutaneous course was found in 26.9% of the perforators, whereas 73.1% revealed a septocutaneous course. Most septocutaneous perforators (50.0%) were found in the distal third and most musculocutaneous perforators (58.5%) in the proximal third (P < 0.001). The majority of perforators originated from the anterior tibial artery (53.0%), followed by the peroneal artery (41.6%), and the popliteal artery (5.1%). Popliteal artery perforators (1.64 mm) were significantly larger than anterior tibial artery (0.91 mm) and peroneal artery perforators (1.02 mm; P < 0.001). These results may facilitate tissue transfer around the lateral lower leg.

Anatomical knowledge gain through a clay-modeling exercise compared to live and video observations.

Clay modeling is increasingly used as a teaching method other than dissection. The haptic experience during clay modeling is supposed to correspond to the learning effect of manipulations during exercises in the dissection room involving tissues and organs. We questioned this assumption in two pretest-post-test experiments. In these experiments, the learning effects of clay modeling were compared to either live observations (Experiment I) or video observations (Experiment II) of the clay-modeling exercise. The effects of learning were measured with multiple choice questions, extended matching questions, and recognition of structures on illustrations of cross-sections. Analysis of covariance with pretest scores as the covariate was used to elaborate the results. Experiment I showed a significantly higher post-test score for the observers, whereas Experiment II showed a significantly higher post-test score for the clay modelers. This study shows that (1) students who perform clay-modeling exercises show less gain in anatomical knowledge than students who attentively observe the same exercise being carried out and (2) performing a clay-modeling exercise is better in anatomical knowledge gain compared to the study of a video of the recorded exercise. The most important learning effect seems to be the engagement in the exercise, focusing attention and stimulating time on task.

Combining fiber dissection, plastination, and tractography for neuroanatomical education: Revealing the cerebellar nuclei and their white matter connections.

In recent years, there has been a growing interest in white matter anatomy of the human brain. With advances in brain imaging techniques, the significance of white matter integrity for brain function has been demonstrated in various neurological and psychiatric disorders. As the demand for interpretation of clinical and imaging data on white matter increases, the needs for white matter anatomy education are changing. Because cross-sectional images and formalin-fixed brain specimens are often insufficient in visualizing the complexity of three-dimensional (3D) white matter anatomy, obtaining a comprehensible conception of fiber tract morphology can be difficult. Fiber dissection is a technique that allows isolation of whole fiber pathways, revealing 3D structural and functional relationships of white matter in the human brain. In this study, we describe the use of fiber dissection in combination with plastination to obtain durable and easy to use 3D white matter specimens that do not require special care or conditions. The specimens can be used as a tool in teaching white matter anatomy and structural connectivity. We included four human brains and show a series of white matter specimens of both cerebrum and cerebellum focusing on the cerebellar nuclei and associated white matter tracts, as these are especially difficult to visualize in two-dimensional specimens and demonstrate preservation of detailed human anatomy. Finally, we describe how the integration of white matter specimens with radiological information of new brain imaging techniques such as diffusion tensor imaging tractography can be used in teaching modern neuroanatomy with emphasis on structural connectivity.

Exploring the validity of assessment in anatomy: do images influence cognitive processes used in answering extended matching questions?

Assessment is an important aspect of medical education because it tests students' competence and motivates them to study. Various assessment methods, with and without images, are used in the study of anatomy. In this study, we investigated the use of extended matching questions (EMQs). To gain insight into the influence of images on the validity of test items, we focused on students' cognitive processes while they answered questions with and without images. Seventeen first-year medical students answered EMQs about gross anatomy, combined with either labeled images or answer lists, while thinking aloud. The participants' verbal reports were transcribed verbatim and then coded. Initial codes were based on a task analysis and were adapted into final codes during the coding process. Results showed that students used more cues from EMQs with images and visualized more often in EMQs with answer lists. Ready knowledge and verbal reasoning were used equally often in both conditions. In conclusion, EMQs with and without images elicit different results in this think aloud experiment, indicating different cognitive processes. They seem to measure different skills, making them valid for different testing purposes. The take-home message for anatomy teachers is that questions without images seem to test the quality of students' mental images while questions with images test their ability to interpret visual information. It makes sense to use both response formats in tests. Using images from clinical practice instead of anatomical drawings will help to improve test validity.

The effect of a daily quiz (TOPday) on self-confidence, enthusiasm, and test results for biomechanics.

Many students in Biomedical Sciences have difficulty understanding biomechanics. In a second-year course, biomechanics is taught in the first week and examined at the end of the fourth week. Knowledge is retained longer if the subject material is repeated. However, how does one encourage students to repeat the subject matter? For this study, we developed 'two opportunities to practice per day (TOPday)', consisting of multiple-choice questions on biomechanics with immediate feedback, which were sent via e-mail. We investigated the effect of TOPday on self-confidence, enthusiasm, and test results for biomechanics. All second-year students (n = 95) received a TOPday of biomechanics on every regular course day with increasing difficulty during the course. At the end of the course, a non-anonymous questionnaire was conducted. The students were asked how many TOPday questions they completed (0-6 questions [group A]; 7-18 questions [group B]; 19-24 questions [group C]). Other questions included the appreciation for TOPday, and increase (no/yes) in self-confidence and enthusiasm for biomechanics. Seventy-eight students participated in the examination and completed the questionnaire. The appreciation for TOPday in group A (n = 14), B (n = 23) and C (n = 41) was 7.0 (95 % CI 6.5-7.5), 7.4 (95 % CI 7.0-7.8), and 7.9 (95 % CI 7.6-8.1), respectively (p < 0.01 between A and C). Of the students who actively participated (B and C), 91 and 80 % reported an increase in their self-confidence and enthusiasm, respectively, for biomechanics due to TOPday. In addition, they had a higher test result for biomechanics (p < 0.01) compared with those who did not actively participate (A). In conclusion, the teaching method 'TOPday' seems an effective way to encourage students to repeat the subject material, with the extra advantage that students are stimulated to keep on practising for the examination. The appreciation was high and there was a positive association between active participation, on the one hand, and self-confidence, enthusiasm, and test results for biomechanics on the other.

Posterior thigh perforator flaps: an anatomical study to localize and classify posterior thigh perforators.

In the last decade perforator flaps have been used increasingly for different indications. Many regions may serve as donor site. In this respect the posterior thigh region (PTR) has been neglected as a potential donor site for many years. The purpose of this study was to provide complete mapping of perforators supplying the posterior thigh region. Twelve fresh cadaver thighs were prepared injecting diluted acrylic paint into the iliac artery. Thereafter the posterior thighs were dissected from medial to lateral, distinguishing the perforators at the level of the superficial fascia. The perforators were localized and origin, source, length and diameter of the perforators were documented. Analysis occurred using ANOVA and the two proportion Z test. The distribution of musculocutaneous and septocutaneous perforators was respectively 69.1% and 30.9% (P = 0.002). The PTR was divided in thirds. Most perforators (53.2%) were found in de middle third of the PTR. The deep femoral artery (DFA) was the main origin of perforators (61.7%), followed by the superficial femoral artery (SFA) (27.7%) and the popliteal artery (PA) (10.6%). The DFA perforators were the longest with a mean length of 13.7 ± 4,69 cm, the SFA perforators were 9.79 ± 3.76 cm and the PA perforators were 8.6 ± 3.37 cm. The PTR offers a sufficient number of suitable perforators to serve as an adequate donorsite for pedicled and free flaps.

A tool for teaching three-dimensional dermatomes combined with distribution of cutaneous nerves on the limbs.

A teaching tool that facilitates student understanding of a three-dimensional (3D) integration of dermatomes with peripheral cutaneous nerve field distributions is described. This model is inspired by the confusion in novice learners between dermatome maps and nerve field distribution maps. This confusion leads to the misconception that these two distribution maps fully overlap, and may stem from three sources: (1) the differences in dermatome maps in anatomical textbooks, (2) the limited views in the figures of dermatome maps and cutaneous nerve field maps, hampering the acquisition of a 3D picture, and (3) the lack of figures showing both maps together. To clarify this concept, the learning process can be facilitated by transforming the 2D drawings in textbooks to a 3D hands-on model and by merging the information from the separate maps. Commercially available models were covered with white cotton pantyhose, and borders between dermatomes were marked using the drawings from the students' required study material. Distribution maps of selected peripheral nerves were cut out from color transparencies. Both the model and the cut-out nerve fields were then at the students' disposal during a laboratory exercise. The students were instructed to affix the transparencies in the right place according to the textbook's figures. This model facilitates integrating the spatial relationships of the two types of nerve distributions. By highlighting the spatial relationship and aiming to provoke student enthusiasm, this model follows the advantages of other low-fidelity models.

Learning anatomy enhances spatial ability.

Spatial ability is an important factor in learning anatomy. Students with high scores on a mental rotation test (MRT) systematically score higher on anatomy examinations. This study aims to investigate if learning anatomy also oppositely improves the MRT-score. Five hundred first year students of medicine (n = 242, intervention) and educational sciences (n = 258, control) participated in a pretest and posttest MRT, 1 month apart. During this month, the intervention group studied anatomy and the control group studied research methods for the social sciences. In the pretest, the intervention group scored 14.40 (SD: ± 3.37) and the control group 13.17 (SD: ± 3.36) on a scale of 20, which is a significant difference (t-test, t = 4.07, df = 498, P < 0.001). Both groups show an improvement on the posttest compared to the pretest (paired samples t-test, t = 12.21/14.71, df = 257/241, P < 0.001). The improvement in the intervention group is significantly higher (ANCOVA, F = 16.59, df = 1;497, P < 0.001). It is concluded that (1) medical students studying anatomy show greater improvement between two consecutive MRTs than educational science students; (2) medical students have a higher spatial ability than educational sciences students; and (3) if a MRT is repeated there seems to be a test effect. It is concluded that spatial ability may be trained by studying anatomy. The overarching message for anatomy teachers is that a good spatial ability is beneficial for learning anatomy and learning anatomy may be beneficial for students' spatial ability. This reciprocal advantage implies that challenging students on spatial aspects of anatomical knowledge could have a twofold effect on their learning.

Do images influence assessment in anatomy? Exploring the effect of images on item difficulty and item discrimination.

Anatomists often use images in assessments and examinations. This study aims to investigate the influence of different types of images on item difficulty and item discrimination in written assessments. A total of 210 of 460 students volunteered for an extra assessment in a gross anatomy course. This assessment contained 39 test items grouped in seven themes. The answer format alternated per theme and was either a labeled image or an answer list, resulting in two versions containing both images and answer lists. Subjects were randomly assigned to one version. Answer formats were compared through item scores. Both examinations had similar overall difficulty and reliability. Two cross-sectional images resulted in greater item difficulty and item discrimination, compared to an answer list. A schematic image of fetal circulation led to decreased item difficulty and item discrimination. Three images showed variable effects. These results show that effects on assessment scores are dependent on the type of image used. Results from the two cross-sectional images suggest an extra ability is being tested. Data from a scheme of fetal circulation suggest a cueing effect. Variable effects from other images indicate that a context-dependent interaction takes place with the content of questions. The conclusion is that item difficulty and item discrimination can be affected when images are used instead of answer lists; thus, the use of images as a response format has potential implications for the validity of test items.

Loosely-guided, self-directed learning versus strictly-guided, station-based learning in gross anatomy laboratory sessions.

Anatomy students studying dissected anatomical specimens were subjected to either a loosely-guided, self-directed learning environment or a strictly-guided, preformatted gross anatomy laboratory session. The current study's guiding questions were: (1) do strictly-guided gross anatomy laboratory sessions lead to higher learning gains than loosely-guided experiences? and (2) are there differences in the recall of anatomical knowledge between students who undergo the two types of laboratory sessions after weeks and months? The design was a randomized controlled trial. The participants were 360 second-year medical students attending a gross anatomy laboratory course on the anatomy of the hand. Half of the students, the experimental group, were subjected without prior warning to station-based laboratory sessions; the other half, the control group, to loosely-guided laboratory sessions, which was the course's prevailing educational method at the time. The recall of anatomical knowledge was measured by written reproduction of 12 anatomical names at four points in time: immediately after the laboratory experience, then one week, five weeks, and eight months later. The strictly-guided group scored higher than the loosely-guided group at all time-points. Repeated ANOVA showed no interaction between the results of the two types of laboratory sessions (P = 0.121) and a significant between-subject effect (P ≤ 0.001). Therefore, levels of anatomical knowledge retrieved were significantly higher for the strictly-guided group than for the loosely-guided group at all times. It was concluded that gross anatomy laboratory sessions with strict instructions resulted in the recall of a larger amount of anatomical knowledge, even after eight months.