The philosophical theme is this practice is about techniques to control your thoughts — learning to be more in charge of your thoughts than they are of you. We consider a couple of stanzas for the Vijnanabharava Tantra:
When you become aware of a desire consider it the time of a snap of fingers, then suddenly let go. Then it returns to the space it just came out of.
Just as you get the impulse to do something, stop. Then, being no more in the preceding impulse or the following one realization blossoms intensely.
As for the physical practice, we work on creating nice alignment with the neck and the upper back. Enjoy!