A case for a lifespan developmental approach to cognition: Hippocampal contributions to memory across the lifespan
Developmental and general approaches to the neural architecture of cognition have reciprocal and beneficial relations. In this talk, I will present research that exemplifies how general computational and animal models point to potential reasons for age differences in memory, and how memory developmental phenomena can help clarify the role of functional subdivisions within brain areas implementing memory. In particular, the hippocampus 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 memories. At the other end of the lifespan, an early decrease in memory specificity is paralleled with relatively intact generalization. I will highlight recent behavioral and neuroimaging evidence suggesting that (1) maturational differences among subfields within the hippocampus contribute to the lead-lag relation between generalization and specificity during childhood and adolescence, (2) scenescent changes within the hippocampus differentially affect specificity and generalization. Based on these results, I propose that developmental changes within the hippocampus affect the fine balance between specificity and generalization across the human lifespan.