Head Chakras

The Head Area, an overview with links

Posterior acupuncture points linked to brain:

(next 2 images are from http://apps.who.int/medicinedocs/en/d/Jh2947e/4.6.html) 

Add caption
Brain and corresponding spiritual anatomy 
These are minor chakras and kshetram.  They have an obvious relationship relationship to the throat, brow and crown chakras, but are also linked to the rest of the body.
From Susan Shumpsky's book Exploring Your Chakras

Links to Details

Approximate location of anterior GV points

Facial points

Points GV20 and GV18 explained

GV20 is the Brahmarandhra and GV18 the Shivarandhra according to this very clear and simple explanation by Dr. Pradeep Ullal, Founder and Head of the Kevala Foundation:

A diagram (source unknown) of the nadis concerned with enlightenment.

The story in the head, as I understand it so far

I have much to learn about what goes on in the subtle head space so some of this may not be 100% accurate but what follows is my understanding so far:  The nadis, often alluded to as "rivers" in the poetry of scripture, like real rivers, course towards an ocean, and have tributaries branching off in other directions.  In the above diagram we have the solar and lunar (pingala and ida) nadi that converge in the brow chakra at the level of the astral body, and through the right and left nostril at the level of the physical body.  Within the physical spinal cord there are, as Paramahansa Yogananda taught, three astral nadis, the finer one less perceptible ones within the grosser ones from sushumna to vajra to chitrini.  The sushumna begins at the base of the spine, (probably GV1 Krittika).  The vajra begins with Kundalini's awakening out of the kanda chakra (probably GV2 Rohini).  The chitrini nadi begins somewhere in the navel chakra.  Leaving the physical chakras now in the hrit chakra of between heart and navel the brahmanadi begins where the soul begins to access its causal body (probably GV8 Magha).  All three connect to the brow chakra.

From root to brow chakras Kundalini moves upward in a spiralling serpentine motion because (I think) it is accessing so many nadis and we can control Her using prana at this stage so ida and pingala are involved.  There is a back and forth between ida and pingala as She ascends the sushumna like an electric current responding to positive and negative currents.

Once She reaches the brow and the soul, now identified with Kundalini, the Guide or Guru within, in the sincere seeker now seeks union with the collective "I" or Siva/Consciousness differentiated and even beyond to transcendence, Siva/Consciousness undifferentiated.  Now the waves of mind (vrittis) need to stop in order to transcend that astral space and enter the causal.  At this stage, as at any stage of spiritual advancement, the soul need grace.  It doesn't just happen by force or will alone.  The heart needs to be into it, devotional practice changes the soul's vibration.  In fact all the chakras need to be purified.  Just as one takes off ones dirty shoes before entering a Hindu temple, then by grace, Kundalini (the purified soul) casts off the astral/active mind and can enter in one movement the innermost sanctum of brahama nadi experiencing the silence of the causal field.  This is where the aspirant begins to feel the crown chakra.  The journey is not complete until Kundalini has pierced the brahmarandhra chakra and entered into the crown chakra.  Laya Yoga mentions even more intermediary steps within the brow chakra.

See bibliography - diagram from the book on Laya Yoga

Sri Vasudeva teaches that the crown chakra is a destination, not a chakra to be purified.   It is a destination.   Therefore all the work of attaining the crown experience, the moksha experience, is done from root to brow.  Even very high spiritual states, in which enlightenment experiences can happen, are still the brow chakra opening up to the crown chakra.

Only the avataurs have attained the crown chakra in fullness and come back, out of compassion for the rest of us stuck in mind and body consciousness.  They return to brahmarandhra chakra, their base of operations, fully anchored in the crown chakra consciousness, the consciousness of purity.  Only they are able to express purity in every chakra, the fullness of every chakra.  This is a great distinction because there is a lot of ego manifesting in the brow chakra.  Without being anchored in crown chakra consciousness the person or soul would still be pulled out of balance by the chakras below the crown.  That's why there are many enlightened teachers but the number of real Teachers, true Teachers - Satgurus - are very very few.  They are great blessings to humanity.  Their ways and their work is mysterious, guided by the highest forces in the universe.  Many New Age writers have written them out as superfluous, but that just tells me that these people haven't met a True Teacher and probably had a bad experience with an "almost" enlightened being.  Even the True Teachers give seekers a hard time, because purification is gut wrenching experience when one's ego is is so powerfully attached.  I speak from person experience!  We need to be anchored in the root chakra in order to gain the benefit of earth school, and the purification that comes through people and situations, karma and time - who, as Sri Vasudeva says, are the servants of the Divine.  We need to respect all the chakras.  But the experience of the crown is what allows us to become fully human, fully in self-mastery and capable of expressing the best that is within us, as well as being a pure instrument of the Divine.  Ultimately no one can know the Creator in fullness or in every moment, yet it's in knowing that each one of us is an avataur in potential is extremely empowering!