Comparison of Team-Based Learning versus Traditional Lectures in Neuroanatomy: Medical Student Knowledge and Satisfaction.

Neuroanatomy is often considered a difficult subject to teach, due to its broad scope, multitude of terms, and high degree of complexity. Thus, newer educational strategies that facilitate learning while also stimulating students by allowing increased student autonomy and group discussions should be carefully considered. This study aimed to evaluate the impact of introducing team-based learning (TBL) in the traditional discipline of neuroanatomy and to measure student knowledge acquisition and perception relative to traditional lectures (TL). A quasi-experimental, nonrandomized study was performed using two consecutive TBL classes (intervention group, n = 157 students, 25% content using TBL) with a TL class (control group, n = 76). Team-based learning sessions included all stages according to the classic description of the method. Student knowledge acquisition was assessed in regularly scheduled tests during the discipline, and their perception regarding TBL was evaluated using a questionnaire (developed by the authors). The groups presented a similar sociodemographic profile (sex and age) and the same performance in another anatomy discipline before the study. Team-based learning was significantly associated with greater acceptance, higher motivation, better student perception, and feelings that the methodology was able to integrate clinical and basic sciences. Nevertheless, according to tests, knowledge acquisition was similar between the TBL and lectures. In conclusion, since TBL is comparable to TL for knowledge acquisition, TBL seems to be a promising strategy to improve the teaching of neuroanatomy in medical schools. It fosters group discussions and increases satisfaction and the perception of integration between clinical and basic sciences.

Male prevalence of acquired color vision defects in asymptomatic carriers of Leber's hereditary optic neuropathy.

PURPOSE: Leber's hereditary optic neuropathy (LHON) is a maternally inherited disease resulting in loss of central vision and dyschromatopsia, caused by mitochondrial DNA point mutations. However, only a subset of the mutation carriers becomes affected, with a higher penetrance in males. This study was conducted to investigate chromatic losses in asymptomatic carriers of the LHON mutation. METHODS: Monocular chromatic discrimination was studied with the Cambridge Colour Test (CCT; Cambridge Research Systems, Ltd., Rochester, UK) along the protan, deutan, and tritan cone isolation axes in 46 LHON carriers (15 men) belonging to the same LHON maternal lineage and 74 age-matched control subjects (39 men). Inclusion criteria were absence of ophthalmic complaints and clear ocular media. A detailed neuro-ophthalmic examination was performed in all the LHON carriers. RESULTS: The differences in threshold between carriers and control subjects were significant for the three cone isolation axes at P < 0.0001. Sixty-five percent of the carriers had abnormal protan and/or deutan thresholds; some of those with higher thresholds also had elevated tritan thresholds (13%). The male thresholds were higher and more frequent than those of the women for the protan and deutan axes (ANOVA; P < 0.05), but not for tritan thresholds. In the most severe losses, the women had instances of diffuse defect whereas all the men displayed a red-green defect. CONCLUSIONS: Male LHON asymptomatic carriers had color vision losses with the red-green pattern of dyschromatopsia typical of patients affected with LHON, which includes elevation of tritan thresholds as well. This predominantly parvocellular (red-green) impairment is compatible with the histopathology of LHON, which affects mostly the papillomacular bundle. In contrast with male losses, female losses were less frequent and severe. These gender differences are relevant to understanding LHON pathophysiology, suggesting that hormonal factors may be of great importance.

Chromatic and luminance contrast sensitivities in asymptomatic carriers from a large Brazilian pedigree of 11778 Leber hereditary optic neuropathy.

PURPOSE: To determine whether asymptomatic 11778 LHON carriers demonstrated impairments in (1) chromatic red/green (R/G) and blue/yellow (B/Y) contrast sensitivity functions (CSF) and in (2) luminance contrast sensitivity functions in the spatial CSF (SCSF) and temporal CSF (TCSF) domains. METHODS: Twenty-five carriers (8 male, 17 female; 34.1 +/- 15.1 years of age) of homoplasmic 11778 LHON from the same well-described family and 30 age-matched controls (17 male, 13 female; 29.2 +/- 7.1 years of age) were tested in one eye, randomly selected. Of the 25 eyes tested, 18 had normal fundus, 5 had swelling and microangiopathy, and 2 had temporal pallor. The R/G and B/Y CSFs were obtained after equiluminance correction with bichromatic horizontal sinusoidal gratings at 0.3, 0.7, and 2 cycles per degree (cpd); the SCSFs were obtained with achromatic gratings at 0.3, 2, 6, and 12 cpd; and the TCSFs were obtained at 2, 10, 20, and 33 Hz with sinusoidal modulation of a 2.7 degrees field with a superimposed spatial Gabor function. RESULTS: Differences between carriers and controls were statistically significant for all spatial frequencies of chromatic and luminance SCSFs, but not for the TCSFs. R/G equiluminance settings of carriers differed from those of controls (P < 0.001), requiring higher luminance in the green; B/Y equiluminance settings were not statistically different in carriers and controls. Fundus findings did not correlate with CS results. CONCLUSIONS: Luminance and chromatic spatial CS losses that affected all tested spatial frequencies, are reported in LHON asymptomatic carriers with the mtDNA 11778 mutation. No losses were found in the temporal CSF. An intriguing finding is that the blue system is substantially spared in this LHON family. These represent subclinical visual impairments in otherwise asymptomatic LHON carriers.