I acknowledge the graphic from the Net.

In this 68th dharana and verse of Vigyana Bhairava Tantra, Shiva says

Meditate on Self as unlimited space

Mind suspended directionless

Shakti reveals 

Shiva takes us to the deep end here. Mind enters avoid in this dharana, formless, directionless, less of everything. It is sunya, the ultimate void and also purna, the ultimate fulfillment. Sunya and purna meet in this dharana.

Akasa, space, is the starting point of the energy pyramid from the top, moving through air, fire, water and down to earth and humans. An energy cycle, looked at another way.  All Vedic rituals worked at completing the cycle. In a yagna, the fire ritual, mantras and yantras brought the energy of space through air and the yagna fire into the water pots arranged around the fire pit, which water when sprayed around people and the earth rejuvenated them with the energy from space. Scientific experiments carried out on Vedic fire rituals show an increased energy level in that environment.

I practise and teach this dharana as an extension breath awareness before leading into body awareness and yoga nidra, following the first few breath oriented dharans of Shiva in Vigyana Bhairava Tantra. Inhale the energy of the universe within, refreshing and recreating. Hold the breath and let it spread through out the body mind, energizing. Exhale fully expanding beyond the body boundaries into space. Hold after exhalation, as one with the energy of the universe, nothing inside, but everything outside. In the void, and in fulfillment. In this state, the mind expands and not knowing where to go stills. One experiences a deep sense of being.

I guess Shiva refers to Shakti here as the state of fulfillment instead of the usual Bhairava or Shiva, since Shakti represents the active energy of Shiva. When i try this dharana what I experience is the quietude of Shiva though.

Try this and see for yourself. Your mind set changes. This dharana liberates and fulfills.