Altered cortical dynamics and adaptive behavior following early-onset sucrose overconsumption

Excessive consumption of added sugar is a growing public health concern, particularly among children and adolescents, with potential impacts on reward-related and cognitive functions. In this study, we examine the effects of early-onset sucrose overconsumption on cortical function and behavior in mice. Using widefield calcium imaging, we monitored activity across the entire dorsal cortex in adult mice that had been pre-exposed to a high-sugar beverage (HSB) from weaning, compared with water-consuming controls, during an odor-sucrose association learning task. Our results show that despite no abnormalities in body weight gain or sugar tolerance responses, HSB-exposed mice exhibited alterations in cortical dynamics and behavioral flexibility. Specifically, HSB mice showed attenuated posterior cortical responses to sucrose consumption, delayed and prolonged learning-related neural activity in the anterior cortex, and weakened anterior-posterior cortical functional connectivity, along with heightened behavioral sensitivity to reward contingency changes. These findings reveal that early-onset sucrose overconsumption reconfigures cortical functionality into adulthood and alters adaptive behavior. These long-lasting impacts of sucrose overconsumption on brain and behavior highlight the need for further research on the detailed mechanisms to mitigate potential adverse effects.