Why do Kundalini Yogi's cover their head?

The practical reason for wearing a head covering can be summed up as follows: Your head is a very sensitive part of the body.

1.) The skull is made up of tiny bones that are constantly moving even if only by micromillimeters and the degree to which they move impacts levels of calmness or anxiety. Covering the head provides a sense of containment and focus while practicing yoga or while doing work that requires clarity of thought. It literally helps "keep your head together".

2.) The forehead consists of porous bone which allows light to pass through it and stimulate the light sensitive pituitary gland. The pituitary is the master gland which regulates all other glands. If it is not stimulated by enough light, a lack of glandular secretion can result including the "feel-goods" dopamine, seratonin and melatonin. Therefore keeping this area of the forehead clear (having the hair up or not wearing bangs) can help with these hormone levels.

Wearing a head covering when you teach or practice enables you to command your sixth center, the Agia Chakra or the third eye point (where we gain access to our intuition). Covering the head stabilizes the cerebral matter and the twenty-six parts of the brain which are interlocked with the neurological system and electromagnetic field. Covering the head creates a focus of the functional circuit of the hemispheres, and tunes the neurological system. Kundalini Yogi’s are taught that the hair is alive and has an energy function. We are training ourselves to be aware of and master our subtle energies and all teachers cover their head and hair with a cotton cloth or wrapped turban. Any natural fiber head covering is functional.