Take a kid who is institutionalized. Institutions tend to vastly under-stimulate kids, for a number of reasons. Now look at that kid's brain.
Current research indicates that our young brains vastly overproduce the number of both neurons and synapsis, and then trim them back. The thing is that we overproduce according to a genetic program but trim back according to experience, so kids who are chronically (and severely) under-stimulated trim back way too many neurons and connections because according to their environment they don't need them. And as we all know, at least for the sexy higher-functioning regions of the brain, a dead neuron never gets replaced.
So life is horrible and we are all going to die.
And I really shouldn't be complaining about studying because I am incredibly privileged and I know it.