“Hikikomori is a coping strategy activated in response to the excessive pressure of social realization typical of modern individualistic societies.”
—Marco Crepaldi, “What Hikikomori Is and What Isn’t?” hikikomoriitalia.it.
Apparently, the hikikimori phenomena is spreading to other countries such as Italy and the United States.
cafebedouin.org 
A few months ago a friend of mine told me about this and we had a long conversation about it. It is really fascinating how we will find coping mechanisms when pushed to extremes.
Sort of like being in a suspended state of shock. The world is going on around you but you are not participating, in fact you wonder how it can keep functioning when you are in this altered state looking from the inside out.
We are interesting creatures.