A foundational knowledge assessment tool to predict academic performance of medical students in first-year anatomy and physiology.

Misalignments in teaching pedagogies between secondary schools and tertiary institutions have exacerbated educational disparities among students from different backgrounds. Given the variation in students' educational background and competencies, there was a need to develop an Anatomy and Physiology (A&P) Foundational Knowledge Assessment to establish the levels of preparedness of first-year medical students. Previous work that focused on the development of the assessment showed it to be effective in measuring students' foundational knowledge in human anatomy and physiology. The aim of this study was to assess the validity of the A&P Foundational Knowledge Assessment in determining students' prior knowledge and predicting academic performance of first-year students in their anatomy and physiology studies. Three hundred seventy first-year students, across two cohort years, 2017 and 2018, completed the A&P Foundational Knowledge Assessment. Data were analyzed through descriptive statistics, analysis of variance, and Pearson's correlation. Results show that for both cohorts ∼30% of students scored ≤55% and were potentially at risk of performing poorly in their anatomy and physiology studies. Pearson's correlation showed a significant relationship between students' performance on the foundational knowledge assessment and their anatomy and physiology assessments. For both cohorts, >10% of students identified by the A&P Foundational Knowledge Assessment were at risk of either failing the course, entering an extended degree program, or being excluded from the program. Results indicate that the assessment is a good predictor for differentiating medical students' performance in first-year anatomy and physiology.NEW & NOTEWORTHY The development of a foundational knowledge assessment tool to predict academic performance of medical students in first-year anatomy and physiology.

What happens to misunderstandings of biomedical concepts across a medical curriculum?

Research on the extent and nature of commonly misunderstood fundamental biomedical concepts across a medical curriculum is scarce. These misunderstandings could point toward robust misconceptions. We examined first whether common misunderstandings persist throughout a medical curriculum, followed by a fine-grained analysis to identify their nature. We designed and administered a 2-tier test to 987 medical students across our curriculum, with 8 questions covering the respiratory and cardiovascular systems, cell division, and homeostatic processes. Proportions of incorrect responses were computed. Four questions where misunderstandings persisted were further qualitatively analyzed. A one-way ANOVA showed the proportion of incorrect responses decreased significantly by students' academic year [F(6, 986) = 96.05, P < 0.001]. While novices and end-of -first-year students showed similar proportion of incorrect responses (P > 0.05), incorrect responses decreased significantly between first years and second years (P < 0.001). Thereafter, the proportion of incorrect responses remained stable from second to final year (P > 0.05), with ∼35% of incorrect responses. Five questions showed no decrease of incorrect responses between second and final years, with two questions where final year students performed marginally better than novices. A Chi-square analysis, with Bonferroni post hoc test, showed certain misunderstandings appeared frequently across the curriculum. The qualitative analysis of the open-ended questions yielded 15 categories of common misunderstandings of fundamental biomedical concepts in all years of training. If educators become aware of commonly misunderstood biomedical concepts, preventative measures could be taken to prevent robust misconceptions.

First-year medical students' naïve beliefs about respiratory physiology.

The present study explored the nature and frequency of physiology naïve beliefs by investigating novices' understanding of the respiratory system. Previous studies have shown considerable misconceptions related to physiology but focused mostly on specific physiological processes of normal respiration. Little is known about novices' broader understanding of breathing in a clinical context. Our study hypothesized that naïve beliefs could hamper participants' ability to understand the interrelatedness of respiratory structures and functions related to breathing during a clinical complication. The study entailed both quantitative and qualitative foci. A two-tier test was designed and administered to 211 first-year medical students. Participants were asked to choose the correct answer out of a set of four options and to substantiate their choices. Questions were purposefully left open to elicit a wide range of responses. Statistical analysis (SPSS) was done to evaluate the frequency of naïve beliefs. Thematic analysis was used to determine themes within the raw data. The majority of participants selected incorrect answers in the multiple-choice question part of the questionnaire. Results from the thematic analysis yielded a considerable range of naïve beliefs about gas exchange, foundational physics, airflow, anatomic structures, and breathing pathways. An awareness of the existence of such naive beliefs in respiratory physiology will allow educators to address them in their teaching and thereby prevent naïve beliefs transforming into misconceptions.

Maternal separation enhances object location memory and prevents exercise-induced MAPK/ERK signalling in adult Sprague-Dawley rats.

Early life stress increases the risk of developing psychopathology accompanied by reduced cognitive function in later life. Maternal separation induces anxiety-like behaviours and is associated with impaired memory. On the other hand, exercise has been shown to diminish anxiety-like behaviours and improve cognitive function. The effects of maternal separation and exercise on anxiety, memory and hippocampal proteins were investigated in male Sprague-Dawley rats. Maternal separation produced anxiety-like behaviours which were reversed by exercise. Maternal separation also enhanced object location memory which was not affected by exercise. Exercise did, however, increase synaptophysin and phospho-extracellular signal-regulated kinase (p-ERK) in the hippocampus of non-separated rats and this effect was not observed in maternally separated rats. These findings show that maternal separation selectively enhanced n memory and prevented activation of the MAPK/ERK signalling pathway in the adult rat hippocampus.

Effect of exercise on synaptophysin and calcium/calmodulin-dependent protein kinase levels in prefrontal cortex and hippocampus of a rat model of developmental stress.

Stress affects the brain differently depending on the timing, duration and intensity of the stressor. Separation from the dam for 3 h per day is a potent stressor for rat pups which causes activation of the hypothalamic-pituitary-adrenal (HPA) axis, evidenced by increased plasma levels of adrenocorticotropin (ACTH) and glucocorticoids. Behaviourally, animals display anxiety-like behaviour while structurally, changes occur in neuronal dendrites and spines in the hippocampus and prefrontal regions involved in emotion and behaviour control. The aim of the present study was to determine whether maternal separation alters expression of synaptic markers, synaptophysin and calcium/calmodulin-dependent protein kinase II (CaMKII), in rat hippocampus and prefrontal cortex. A second aim was to determine whether voluntary exercise had a beneficial effect on the expression of these proteins in rat brain. Maternal separation occurred from postnatal day 2 (P2) to P14 for 3 h per day. Exercised rats were housed in cages with attached running wheels from P29 to P49. At P65, the prefrontal cortex and hippocampus were removed for protein quantification. Maternal separation did not have any effect while exercise increased synaptophysin and CaMKII in the ventral hippocampus but not in the dorsal hippocampus or prefrontal cortex. Since the ventral hippocampus is associated with anxiety-related behaviour, these findings are consistent with the fact that voluntary exercise increases anxiety-like behaviour and improves learning and memory.

Effect of exercise on learning and memory in a rat model of developmental stress.

Adverse life events occurring in early development can result in long-term effects on behavioural, physiological and cognitive processes. In particular, perinatal stressors impair neurogenesis in the hippocampus which consequently impairs memory formation. Exercise has previously been shown to have antidepressant effects and to increase cognitive functioning by increasing neurogenesis and neurotrophins in the hippocampus. The current study examined the effects of maternal separation, which has been shown to model anxiety in animals, and the effects of exercise on learning and memory. Forty-five male Sprague-Dawley rats were divided into four groups, maternally separated / non-runners, maternally separated / runners, non-separated / runners and non-separated / non-runners. Maternal separation occurred from postnatal day 2 (P2) to 14 (P14) for 3 h per day. Exercised rats were given voluntary access to individual running wheels attached to their cages from P29 to P49. Behavioural testing (Morris water maze (MWM) and object recognition tests) took place from P49 to P63. Maternally separated rats showed no significant difference in anxiety levels in the elevated plus maze and the open field compared to the normally reared controls. However, rats that were allowed voluntary access to running wheels showed increased levels of anxiety in the elevated plus maze and in the open field. Maternal separation did not have any effect on memory performance in the MWM or the object recognition tasks. Exercise increased spatial learning and memory in the MWM with the exercised rats displaying a decreased latency in locating the hidden platform than the non-exercised rats. The exercised rats spent significantly less time exploring the most recently encountered object in the temporal order task in comparison to the non-exercised controls, therefore showing improved temporal recognition memory. All groups performed the same on the other recognition tasks, with all rats showing intact memory performance. Results indicate that maternal separation had little effect on the rats whereas exercise enhanced both spatial and recognition memory.

Basomedial hypothalamic injections of neuropeptide Y conjugated to saporin selectively disrupt hypothalamic controls of food intake.

Neuropeptide Y (NPY) conjugated to saporin (NPY-SAP), a ribosomal inactivating toxin, is a newly developed compound designed to selectively target and lesion NPY receptor-expressing cells. We injected NPY-SAP into the basomedial hypothalamus (BMH), just dorsal to the arcuate nucleus (ARC), to investigate its neurotoxicity and to determine whether ARC NPY neurons are required for glucoprivic feeding. We found that NPY-SAP profoundly reduced NPY Y1 receptor and alpha MSH immunoreactivity, as well as NPY, Agouti gene-related protein (AGRP), and cocaine and amphetamine-related transcript mRNA expression in the BMH. NPY-SAP lesions were localized to the injection site with no evidence of retrograde transport by hindbrain NPY neurons with BMH terminals. These lesions impaired responses to intracerebroventricular (icv) leptin (5 microg/5 microl x d) and ghrelin (2 microg/5 microl), which are thought to alter feeding primarily by actions on ARC NPY/AGRP and proopiomelanocortin/cocaine and amphetamine-related transcript neurons. However, the hypothesis that NPY/AGRP neurons are required downstream mediators of glucoprivic feeding was not supported. Although NPY/AGRP neurons were destroyed by NPY-SAP, the lesion did not impair either the feeding or the hyperglycemic response to 2-deoxy-D-glucose-induced blockade of glycolysis use. Similarly, responses to glucagon-like peptide-1 (GLP-1, 5 microg/3 microl icv), NPY (5 microg/3 microl icv), cholecystokinin octapeptide (4 microg/kg ip), and beta-mercaptoacetate (68 mg/kg ip) were not altered by the NPY-SAP lesion. Thus, NPY-SAP destroyed NPY receptor-expressing neurons in the ARC and selectively disrupted controls of feeding dependent on those neurons but did not disrupt peptidergic or metabolic controls dependent upon circuitry outside the BMH.

The impact of voluntary exercise on relative telomere length in a rat model of developmental stress.

BACKGROUND: Exposure to early adverse events can result in the development of later psychopathology, and is often associated with cognitive impairment. This may be due to accelerated cell aging, which can be catalogued by attritioned telomeres. Exercise enhances neurogenesis and has been proposed to buffer the effect of psychological stress on telomere length. This study aimed to investigate the impact of early developmental stress and voluntary exercise on telomere length in the ventral hippocampus (VH) and prefrontal cortex (PFC) of the rat. Forty-five male Sprague-Dawley rats were categorised into four groups: maternally separated runners (MSR), maternally separated non-runners (MSnR), non-maternally separated runners (nMSR) and non-maternally separated non-runners (nMSnR). Behavioural analyses were conducted to assess anxiety-like behaviour and memory performance in the rats, after which relative telomere length was measured using qPCR. RESULTS: Maternally separated (MS) rats exhibited no significant differences in either anxiety levels or memory performance on the elevated-plus maze and the open field compared to non-maternally separated rats at 49 days of age. Exercised rats displayed increased levels of anxiety on the day that they were removed from the cages with attached running wheels, as well as improved spatial learning and temporal recognition memory compared to non-exercised rats. Exploratory post-hoc analyses revealed that maternally separated non-exercised rats exhibited significantly longer telomere length in the VH compared to those who were not maternally separated; however, exercise appeared to cancel this effect since there was no difference in VH telomere length between maternally separated and non-maternally separated runners. CONCLUSIONS: The increased telomere length in the VH of maternally separated non-exercised rats may be indicative of reduced cellular proliferation, which could, in turn, indicate hippocampal dysfunction. This effect on telomere length was not observed in exercised rats, indicating that voluntary exercise may buffer against the progressive changes in telomere length caused by alterations in maternal care early in life. In future, larger sample sizes will be needed to validate results obtained in the present study and obtain a more accurate representation of the effect that psychological stress and voluntary exercise have on telomere length.