RepleteDivide t1_j83t6j1 wrote

And just in case it isn't common knowledge, the ultimate cause of those physiological processes is the evolution of a social species. Pre-human apes became highly social as fruit-eating tree-dwelling creatures, and then as they came out of the trees and evolved over the generations as upright-standing apes, the social systems remained, and when H. sapiens evolved, the social system was still there. We need human connection because of that evolution that created our bodies, and that is where the cortisol and psychological distress vs joy comes into play.