Epigenomic settings control gene regulation in both developing and postmitotic tissue, whereas abnormal regulation of epigenomic settings has been implicated in many developmental and neurological disorders. Evidence is emerging for the roles of epigenetic mechanisms in the mature nervous system, in the dynamic processes of learning and memory. The discovery of the involvement of DNA methylation and histone acetylation and methylation in neuronal processing provides a possible answer to the long-standing riddle of how memories persist in a biological system whose cellular composition is in a constant state of flux and renewal. This mini review focuses on present research in DNA methylation and histone posttranslational modifications in learning and memory, age-related cognitive decline, and related pathological disorders.