I find the reference to “shepherd's crook” most interesting.
Q: Is this a correspondence that starts at the basal chakra which relates to the sexual center as described by Mouravieff?
A: No. The "sexual center" corresponds to the solar plexus.
Lower moving center - basal chakra
Lower emotional - sexual chakra
Lower intellectual - throat chakra
Higher emotional - heart chakra
Higher intellectual - crown chakra
Q: (L) What about the so-called seventh, or "third eye" chakra?
A: Seer. The union of the heart and intellectual higher centers.
[Laura's note: This would "close the circuit" in the "shepherd's crook" configuration.]
Laura also mentions the “shepherd's crook” in The Wave, Book Two, Chapter 10:
During this same time, there was a great deal of what could only be called psychokinetic activity. Many people saw this as a "sign" of "spiritual achievement." I didn't. To me, it was useless and distracting. My studies had shown me that most, if not all, such events were a result of "short circuited" kundalini forces; energies of the soul, entering via the basal chakra, diverted by the brainstem into the environment. I was distressed that they were being "diverted" at this juncture, rather than flowing, as was proper, in the "Shepherd's Crook" configuration to the third eye.
Although these two reference don't actually mention a psychic channel going from the base of the spine to the crown chakra and then curving down to the third eye, the image of the shepherd's crook certainly suggest it.
I'd like to propose that the “shepherd's crook,” as Laura call it, is not the only kundalini-psychic curve. There is what is called the
sushumna and I use the term in the sense of the following quote from,
Talks with Sri Ramana Maharshi, 9th Edition, published by TN Venkatraman, Page 575:
If one concentrates on the sahasrara [crown chakra] there is no doubt that the ecstasy of samadhi ensues. The vasanas, that is the latent mental tendencies, are not however destroyed. The yogi is therefore bound to wake up from the samadhi because release from bondage has not yet been accomplished. He must still try to eradicate the vasanas inherent in him so that they cease to disturb the peace of his samadhi. So he passes down from the sahasrara [crown chakra] to the Heart through what is called the jivanadi [psychic nerve from crown chakra to heart], which is only a continuation of the sushumna. The sushumna is thus a curve. It starts from the lowest chakra, rises through the spinal cord to the brain and from there bends down and ends in the Heart. When the yogi has reached the Heart, the samadhi becomes permanent. Thus we see that the Heart is the final centre.
For those not familiar with Ramana Maharshi he was one of the most celebrated saints of India (1879 to 1950). Wikipedia has a fair description of him.
http://en.wikipedia.org/wiki/Ramana_Maharshi
Ramana Maharshi when 23 years old or so.
From my limited experience, I would have to say that the sushumna curve includes the shepherd's crook, that is the “third eye” is part of the sushumna.