Adolescent Sugar-Induced Miswiring of Hippocampal Neurons Drives Adult Motivational Dysfunction in rats

Adolescent-born dentate gyrus granule neurons causally mediate adult reward-seeking behavior in rats, but adolescent sucrose overconsumption abolishes this function.

• Why it matters: The study addresses how adolescent sugar overconsumption produces lasting motivational deficits by clarifying whether newly integrated hippocampal neurons drive adult reward behavior.
• What they did: Using causal tests of adolescent-born dentate gyrus granule neurons, the authors show that sucrose overconsumption during adolescence selectively remodels synaptic inputs and disrupts their functional integration.
• The result: The findings link adolescent sugar exposure to impaired synaptic remodeling and integration of adult reward circuitry, implying a mechanism for persistent motivational dysfunction.