The researchers suggest that lonely people's thoughts are directed inwards due to a lack of social experiences, and this is what alters the brain. But I wonder how many people just have brains like this, and feel lonely as a consequence?
There might be a few cases where loneliness is "caused" by a problem in the brain, but I would wager the vast majority of cases are caused by what I described above - lack of regular meaningful interaction with a partner over an extended period.
When I'm single and without many friends around, I rather just slide past life. I don't latch onto interesting stuff as much. I have my thought processes and goals and since nobody asks how my day was, there's no point in remembering minor inconsequential stuff. But as you don't need to remember them, you don't even notice them. Like even a mundane task of taking a package to the post will be more of an emotional adventurous roller coaster when I have people in my life and rather a goal-directed straightforward thing when not.
In other words, assuming that holds, there can’t be “I” if there’s no one else.
With that theory in mind, when I experience this “sliding past life” (quite an apt analogy), I actually see it as evidence of myself in some ways becoming less conscious, or at least less self-aware.
It’d seem that some don’t experience such a contrast between being social and being alone; I suspect it could be because these maps their minds build have more “inertia” and are used in absence of the “territory” for longer. In a way that must be a nice feature, though on the other hand this might imply that such models aren’t as tightly coupled to reality.