One of the techniques of what Westerners call Stoicism is the negative visualization that Nemoto has his patients/clients undergo - imagining you only have a few weeks to live, that you've lost your material wealth, that you've lost someone important to you, thinking about your death. Also, intentional self-deprivation.

"A Guide to the Good Life: the Ancient Art of Stoic Joy" was well worth reading and has a whole chapter on negative visualization as a means for overall more positive thinking.