Anterior and posterior hippocampus macro- and microstructure across the lifespan in relation to memory-A longitudinal study.

There is evidence for a hippocampal long axis anterior-posterior (AP) differentiation in memory processing, which may have implications for the changes in episodic memory performance seen across development and aging. The hippocampus shows substantial structural changes with age, but the lifespan trajectories of hippocampal sub-regions along the AP axis are not established. The aim of the present study was to test whether the micro- and macro-structural age-trajectories of the anterior (aHC) and posterior (pHC) hippocampus are different.

Development and Decline of the Hippocampal Long-Axis Specialization and Differentiation During Encoding and Retrieval of Episodic Memories.

Change in hippocampal function is a major factor in life span development and decline of episodic memory. Evidence indicates a long-axis specialization where anterior hippocampus is more engaged during encoding than during retrieval, and posterior more engaged during retrieval than during encoding. We tested the life span trajectory of hippocampal long-axis episodic memory-related activity and functional connectivity (FC) in 496 participants (6.

Decoupling of large-scale brain networks supports the consolidation of durable episodic memories.

At a large scale, the human brain is organized into modules of interconnected regions, some of which play opposing roles in supporting cognition. In particular, the Default-Mode Network (DMN) has been linked to operations on internal representations, while task-positive networks are recruited during interactions with the external world. Here, we test the hypothesis that the generation of durable long-term memories depends on optimal recruitment of such antagonistic large-scale networks.

Mechanisms underlying encoding of short-lived versus durable episodic memories.

We continuously encounter and process novel events in the surrounding world, but only some episodes will leave detailed memory traces that can be recollected after weeks and months. Here, our aim was to monitor brain activity during encoding of events that eventually transforms into long-term stable memories. Previous functional magnetic resonance imaging (fMRI) studies have shown that the degree of activation of different brain regions during encoding is predictive of later recollection success.