Adaptive learning systems need to meet two complementary and partially conflicting goals: detecting regularities in the world versus remembering specific events. The hippocampus (HC) keeps a fine balance between computations that extract commonalities of incoming information (i.e. generalization through pattern completion) and computations that enable encoding of highly similar events into unique representations (i.e. memory specificity through pattern separation). During early ontogeny, the rapid and cumulative acquisition of world knowledge through generalization contrasts slower improvements in the ability to lay down highly specific, long-lasting episodic memories. At the other end of the lifespan, an early decrease in memory specificity is paralleled with relatively intact generalization. In this talk, I will highlight recent behavioral and neuroimaging evidence suggesting that maturational differences among subfields within the hippocampus contribute to the lead-lag relation between generalization and specificity during childhood and adolescence, and present preliminary results of a study investigating how scenescent changes within the hippocampus affect specificity and generalization. In sum, I propose that developmental changes within the hippocampus affect the fine balance between specificity and generalization across the human lifespan.