We have private access to it thanks to a DNA type key and sometimes, when this key fails, we can have access to portions of memory belonging to others. This model makes it possible to describe quite reasonably paranormal phenomena, telepathy, talking with the dead, near-death trips, dreams,... For example, two distant twins communicate ... because they share the same memory area to which they have the key. If I see my long dead mother in a dream, it is not because she would be alive somewhere, but because, in the secondary state of sleep and because our DNAs are close, I had a furtive access to a portion of her memory and, when I woke up, I painfully reconstructed a scenario in which she would have said a few words to me. Why not?
And if you wonder about the nature of this parallel space where the memory of hunanity is located, think about this ocean of electro-magnetic waves in which we are immersed and to which we only have access with the help of transceivers like our smartphones, radios, televisions, computers, ... which do not store anything.
What do you think of that?