High fat diet intake during pre and periadolescence impairs learning of a conditioned place preference in adulthood

<p>Abstract</p> <p>Background</p> <p>Brain regions that mediate learning of a conditioned place preference (CPP) undergo significant development in pre and periadolescence. Consuming a high fat (HF) diet during this developmental period and into adulthood can lead to learning impairments in rodents. The present study tested whether HF diet intake, consumed only in pre and periadolescence, would be sufficient to cause impairments using a CPP procedure.</p> <p>Methods</p> <p>Rats were randomly assigned to consume a HF or a low fat (LF) diet during postnatal days (PD) 21-40 and were then placed back on a standard lab chow diet. A 20-day CPP procedure, using HF Cheetos^®as the unconditioned stimulus (US), began either the next day (PD 41) or 40 days later (PD 81). A separate group of adult rats were given the HF diet for 20 days beginning on PD 61, and then immediately underwent the 20-day CPP procedure beginning on PD 81.</p> <p>Results</p> <p>Pre and periadolescent exposure to a LF diet or adult exposure to a HF diet did not interfere with the development of a HF food-induced CPP, as these groups exhibited robust preferences for the HF Cheetos^®food-paired compartment. However, pre and periadolescent exposure to the HF diet impaired the development of a HF food-induced CPP regardless of whether it was assessed immediately or 40 days after the exposure to the HF diet, and despite showing increased consumption of the HF Cheetos^®in conditioning.</p> <p>Conclusions</p> <p>Intake of a HF diet, consumed only in pre and periadolescence, has long-lasting effects on learning that persist into adulthood.</p

Leadership emergence in face-to-face and virtual teams : a multi-level model with agent-based simulations, quasi-experimental and experimental tests

With leadership as a major predictor of team performance in both face-to-face and virtual teams, research on differences in leadership emergence in these contexts seems warranted. We offer a multi-level model analyzing the roles of degree of team virtuality and density of social network ties as boundary conditions on leadership emergence, viewed as a fundamentally social–cognitive process. Using agent-based modeling and simulations, our results suggest that virtuality moderates the relationships between cognitive ability, extraversion, and self-efficacy (as independent variables) and leadership emergence (as dependent variable); and density of network ties serves as a moderator for the associations of cognitive ability and self-efficacy with leadership emergence. Subsequent quasi-experimental and experimental tests support the role of density of network ties as a moderator for the association of extraversion with leadership emergence. Implications of these findings and future paths for research bridging the fields of leadership, team virtuality and social networks are discussed