@InvaderXan
I was always intrigued with the concept of the Trill on Star Trek: an intelligent alien species that has a symbiotic relationship with another species that is vastly different than them. The Trill live about a human lifespan, but the Trill symbionts life for many millennia, and one symbiont will live inside multiple Trill over its life, and will share the experiences of all its previous hosts with its current one.
Humans don’t have anything like this. You could come up with some sort of alien wherein experiences can be shared across generations in a way that each individual becomes, in a small part, a part of the individuals whose memories they’ve inherited.