As a result, the relaxation is progressing in the middle of the back of the head and in the central part of the head. The head is, of course, originally divided into the right and left hemispheres, but it feels as if the right and left hemispheres are moving independently, as if they are being pulled apart or moving individually.
The sensation is that something that was glued together is being peeled off. Because the area was solidified, there is sometimes a slight pain-like sensation along with the feeling of being peeled off, but it is not very strong and is temporary. Occasionally, there is also a tingling sensation like a thin, weak needle, but that is also the kind of sensation where something is stretched and a thread is cut, allowing it to become free. Even though it is called pain, it is only a very slight sensation, and along with such slight sensations, I feel that the middle of the head is becoming increasingly relaxed.
Movement appears in the forehead and between the eyebrows, and I feel a pressure as if something is being pushed from between the eyebrows towards the back, and a sensation that is gradually connecting from between the eyebrows to the back of the head.
It doesn't seem that this part has completely started moving yet, but I feel that it is steadily progressing.
Along with this, recently, my intuition has become more accurate, and things that I thought "this might happen" are becoming more accurate. However, it is still not perfect.
From such things, I feel that this part is becoming more active.
As a result, the sensation extends to the neck, and the area below that, such as the chest and abdomen, does not yet have as much of a sense of being divided into left and right, but I have a feeling that it will.
To express this state, I think the following diagram from Kriya Yoga is similar.
From Kriya Yoga Darshan (written by Swami Shankarananda Giri):
It seems that there are also detailed schools of thought within Kriya Yoga. According to the school of thought of the same author, the Sushumna, which is the pathway for Kundalini, does not exist from the beginning, but rather, after the Ida and Pingala are formed, and then, due to their movement to the left and right, a pathway for Kundalini is created in the empty space in the middle.
Even though it's just a little bit, I feel something similar. My throat has opened to some extent, but in this sense, it is still not fully open, and rather, it feels like it is blocked.