There's an awesome 10-page article in today's NYTimes.com about Carl Jung's mysterious, almost mythological "Red Book"... I recommend page 2 in particular (Wishydig). Of Jung's 1913 breakdown:
My vote is for "descent into the underworld." The journal/book is available for $100.00, and will be published this October. Interlibrary loan, anyone?
It has been characterized variously as a creative illness, a descent into the underworld, a bout with insanity, a narcissistic self-deification, a transcendence, a midlife breakdown and an inner disturbance mirroring the upheaval of World War I.