My pragmatic understanding of this as someone who is a life scientist (but not a neuroscientist) is that neuroplasticity itself is sort of like a skill, and if you don’t use it, you lose it. That is to say that you needn’t rush to cram in new knowledge, but you should continue to indulge your hunger for knowledge. If you keep expanding your horizons and ways of thinking, you’ll maintain a high level of neuroplasticity as you age