Some people might describe this as "opening," but I didn't feel like a door was opening. Instead, I felt like a wall or a board was rising. First, there was a sensation of something being pushed from slightly behind the eyebrows towards the forehead (the front of the face). I didn't consciously do this; it just happened while I was meditating. And it wasn't just a pushing sensation; I also felt like something that was originally lying down was standing up. It felt like a board was standing up, but until that moment, I hadn't been aware that there was a board there. When I felt it standing up, I suddenly thought, "Maybe it was always lying there, and I just didn't notice."

Not long after that, energy also filled the channels running vertically in the lower part of the back of the head, near the base of the neck. The pressure increased, and I felt like the channels were being strengthened, expanding from the inside out.

Basically, I was just sitting and meditating normally that day, and I didn't intend for this to happen. My whole body was filled with energy, but I wasn't particularly focusing on my forehead. However, at a certain moment, a change appeared in my forehead, and then, shortly after, a change appeared in the lower part of the back of my head.

I felt that energy was flowing more strongly not only in the back of the head but also in the neck, and I felt like it was descending throughout my body, like oil dripping, permeating, like drops of oil or water.

Recently, I've been feeling that the area from the forehead to the third eye is filled with energy, and the Sahasrara (crown chakra) is becoming more active. Correspondingly, I've been feeling that the area around the root of the legs, the perineum, is becoming more active, with a stronger pulse sensation than before.

In yoga, it is said that changes in the Ajna chakra (third eye) always correspond to the Muladhara chakra (base chakra), and that one change always manifests in the other. Recently, I've been experiencing such changes.