We rely on our ability to recall memories, particularly positive memories, to guide our future behaviors, making it adaptive to retain salient events. In adults, positive emotion's effects on memory encoding and consolidation have been well characterized, including the selective prioritization of central, salient information ('gist'), over peripheral context and transformation for long-term retention. Do young children similarly prioritize emotional memories? Brain structure and function undergoes extensive, protracted development across childhood, particularly between ages 4-6; with maturation of the medial temporal lobe and amygdala continuing into early childhood, and connections to prefrontal cortex (PFC) extending into adolescence. However, without top-down processes from PFC, children are more reactive to positive events. At the same time, early developing mnemonic functions seem developmentally advantageous for the acquisition of conceptual knowledge, and an early reliance on 'gist'-based memory over fine details and weak relational binding ability seem to mirror characteristic effects of positive emotional memory. It is therefore possible that the immature memory system is well suited to emphasize the adaptive functions of memory. Yet, critically little work has tested how mechanisms in the immature memory system support positively-valanced memories. The goal of this proposal is to determine how these adaptive memories are formed and stored across early childhood and to relate these measures to the pattern of developmental changes in supporting brain morphology. This proposal details two experiments with children (4-8 years old) and young adults (18-35) utilizing novel behavioral manipulations and structural neuroimaging. In Aim 1, we propose a behavioral experiment to characterize how positive information is selectively prioritized over neutral information in memory in early childhood. In Aim 2, a behavioral experiment will examine developmental differences in the organization and content of positive memories. While research has shown an age-related tendency towards 'gist'-memory, little work has systematically tested developmental differences in the trade-off of details and integration for salient information. In an exploratory Aim 3, we will use structural neuroimaging to examine the relationship between positive memory benefits and the maturation of white matter tracts that facilitate information processing across cortical and sub-cortical structures. The proposed aims will therefore advance the development of novel, childfriendly behavioral paradigms to determine how adaptive memories are formed and stored across early development. This research will provide the foundation to study the antecedents of emotion dysregulation disorders and inform practices for developing socio-emotional skills in early childhood.