Figure 3.

During aging, the hippocampus undergoes remodeling, which has an impact on learning and memory capacity. A decrease in BDNF levels can be observed, as well as volume reductions of the hippocampus. Decreased BDNF levels may influence the density of dendritic spines and the rate of adult hippocampal neurogenesis. Reductions in these two systems may contribute (on a morphological level) to the age-dependent volume reduction and may also contribute (among other factors) to the decrease in hippocampal learning and memory reductions.