Time in a trap

Having been exposed to cosmology from a very young age, I was almost comfortable with too many established facts that are beyond the logical framework - space is endless, time has a beginning, and lately, with the advent of relativity, spacetime is a malleable framework with something as simple as an increase in speed with respect to a reference frame, or something as simple as mass. 

Surely something didn't fit in. Objective measurements revealed an anomaly with the presumed absolute structure of time and its human experience and measurement with clocks. I grappled for two decades trying to just grasp all of this into a single framework. But seldom do realisations come from outside, when all it needs is a flowering from inside.

Suddenly a few days back I came across an article published in Nature Neuroscience.

Voila! Very much like colours, smell, taste, sounds and touch, which have no objective existence in the Universe except being created by the brain, even spacetime is such a construct. 

I am still grappling with how it hit me, but one thing is for certain, the answer may not lie in more physics - but deeper into the brain. 

I wonder if there are species that don't have this construct. Would they exist in our interpretation of sensory stimulation? Would they have any experience, or are they as eternal in experience already that humans strive for years through rigorous meditation? 

However, the more this realisation gets deeper in me, the more I grapple in awe as to how the nature of what we call the Universe is - how does it exist, and what does it mean for something to 'exist', ontologically? Is it like a book that has all the chapters already written, and we are just thinking of reading it chapter by chapter with the construct of time?

A question to ponder on: assuming spacetime would be analogous to a learned latent representation of the underlying causal reality we won't know through sensory intepretation, what computational problem does the brain solve by constructing a world with three dimensions of space and one dimension of time?