The Nasikagra mudra | drishti could swiftly arouse the kundalini energy in the muladhara chakra. Its effect on the nervous system is similar to that of Bhastrika pranayama, even stronger.
Due to its strong effect on the nervous system, the nasikagra mudra should be done carefully, only while sitting and under the guidance of a guru. People with optic and neurological issues should not do nasikagra mudra. They can practice the Nasikagra Hand Mudra instead.
The prescribed asana for nasikagra mudra is siddhasana/siddha yoni asana or the Padmasana. This is to prevent a sudden drop in body temperature and maintain a healthy heart rate.
Start with eyes closed and internally visualise the bridge of the nose. Lightly open the eyes and gaze at the tip of the nose. Breathe normally, not too deep neither too light. Breathe calmly. As you focus, the eyes will cross and the images blur. Focus on the nose tip only.
Breathe mindfully. Observe any differences in the flow of the breath. You may feel that one side is more open than the other. Just observe. Do not alter the breath. When the eyes fatigue, close them and allow your optic nerves to relax. Observe the images, colours, etc you see as you gaze inwardly in the Chidakasha (behind your eyelids). If you see moving shapes, lines, colours, flashing or blinking lights, focus on them. They activate the inner brain.
Important: Once the eyes find the point, relax them. Do not force them to cross them. Channelise your awareness to your BREATH. Breathe lightly but thoroughly. Notice how the lightness of the inhalation stimulates the optic nerves (centre of the eyebrows). Follow the electrical sensation until it dissipates. Then, exhale.
Kundalini manifests in many ways and forms. She could be felt as electricity crawling your skin. She is the light, colours, shapes, patterns, images and various visions you see behind your closed eyelids.
As the kundalini energy builds up inside, she emits all these manifestations. Commonly, a light appears inside. Some see yellow or blue light. It is the jyoti or inner light. It is the colour of the sushumna nadi. It is similar to the light we see after rubbing our eyes. The purpose of nasikagra mudra is to bask in that light, colour (or image) which could powerfully absorb the mind.
Practice Note: Choose one mudra for the eyes and practice it for several weeks or months. Let one technique grow in you first. Also, do not force it to happen. If there are days that doing them is heavy, then just relax your eyes as you prepare for meditation. Follow what your body and energy tell you. If you are tired and restless, then rest. It’s probably what you all need to make it happen.
Here’s a guided practice for you. Apply the nasikgra hast mudra (hand) and or drishti (eyes) as you practice the Nadi Shodhana.