Experience and neuronal activity can induce dynamic changes in myelination during development and in adult life, suggesting a new form of plasticity to adapt brain function to environmental stimuli. Myelin remodeling is driven mainly by newly-formed oligodendrocytes from precursors cells. However, the role of mature oligodendrocytes in plastic changes of myelin is less known. Using inducible transgenic mice expressing the DREADD receptor hM3Dq in PLP+ myelinating cells, we have analysed the impact of

CNO on myelin remodelling and behaviour. I will summarize our data showing that  chronic chemogenetic activation of PLP+ myelinating cells modulates the nodes of Ranvier and neuronal activity and that these maladaptive myelination changes are sufficient to induce alterations in emotional stress responses.