FIGURE 2.

Adaptive myelination in adulthood. Environmental cues increase neuronal activity in specific circuits, leading to the release of ligands such as glutamate, adenosine and BDNF (small colored circles) that promote the expansion of existing internodes. In adult rodents, these ligands drive OPC proliferation and differentiation but this aspect of de novo myelination seems negligible in healthy adult humans. Adaptive myelination in adulthood increases network synchronization and improves performance in a variety of tasks. Myelinating agents such as Clemastine fumarate increase adaptive myelination while some forms of EA or prolonged social deprivation in adulthood impair it. EA, early adversity; OL, mature oligodendrocyte; OPC, oligodendrocyte progenitor cell.