Front and Back Flipping for Neurobiology! Developing a Hybrid Upper-Division Lab Course.

Flipped instruction using online enrichment is a popular way to enhance active learning in the laboratory setting. Graduate student teaching assistants at University of California, Irvine flipped an upper division undergraduate neurobiology and behavior lab using the new online software platform "Rocketmix." The following research study compares the impact of pre-lab online instruction (front flipping) and post-lab online instruction (back flipping) on student exam performance. We describe a novel method for unbiased categorization of exam questions by degree of difficulty. Multi-choice instruction encourages students to consider all distractors and discourages verbal cues and process of elimination techniques. Eighteen identical questions were evenly distributed across exam versions with multiple choice instruction (single answer) or a more challenging multi-choice instruction (more than one answer). Student performance on multiple choice questions were used to categorize the degree of difficulty of questions that were presented in multi-choice format. Our findings reveal that pre-lab instruction resulted in better student performance compared with post-lab instruction on questions of moderate difficulty. This effect was significant for both male and female students. Student survey data on the flipped lab format is provided, indicating that students appreciated the online instructional modules, finding them both informative and useful during lab exercises and exams.

Frontoparietal connectivity in substance-naïve youth with and without a family history of alcoholism.

Frontoparietal connections underlie key executive cognitive functions. Abnormalities in the frontoparietal network have been observed in chronic alcoholics and associated with alcohol-related cognitive deficits. It remains unclear whether neurobiological differences in frontoparietal circuitry exist in substance-naïve youth who are at-risk for alcohol use disorders. This study used functional connectivity magnetic resonance imaging and diffusion tensor imaging to examine frontoparietal connectivity and underlying white matter microstructure in 20 substance-naïve youth with a family history of alcohol dependence and 20 well-matched controls without familial substance use disorders. Youth with a family history of alcohol dependence showed significantly less functional connectivity between posterior parietal and dorsolateral prefrontal seed regions (ps<.05), as compared to family history negative controls; however, they did not show differences in white matter architecture within tracts subserving frontoparietal circuitry (ps>.34). Substance-naïve youth with a family history of alcohol dependence show less frontoparietal functional connectivity in the absence of white matter microstructural abnormalities as compared to youth with no familial risk. This may suggest a potential neurobiological marker for the development of substance use disorders.

Sex differences in adolescent white matter architecture.

BACKGROUND: Sex-specific trajectories in white matter development during adolescence may help explain cognitive and behavioral divergences between males and females. Knowledge of sex differences in typically developing adolescents can provide a basis for interpreting sexual dimorphisms in abilities and actions. METHOD: We examined 58 healthy adolescents (12-14years of age) with diffusion tensor imaging (DTI). Diffusion parameters fractional anisotropy (FA), and mean (MD), radial (RD), and axial diffusivities (AD) were subjected to whole-brain voxel-wise group comparisons using tract-based spatial statistics. Sex differences in white matter microstructure were examined in relation to pubertal development. RESULTS: Early adolescent females (n=29) evidenced higher FA in the right superior corona radiata, higher FA and AD in bilateral corticospinal tracts (≥164µl, p<.01), and lower MD in the right inferior longitudinal fasciculus (ILF) and left forceps major (≥164µl, p<.01) than age-matched males (n=29). Males did not show any areas of higher FA or lower MD than females, but had higher AD in the right superior longitudinal fasciculus, ILF, and forceps minor (≥ 164µl, p<.01). Pubertal stage did not account for sex disparities. CONCLUSION: In early adolescence, females' motor tracts may reflect widespread changes, while males may undergo relatively more microstructural change in projection and association fibers.