The dimensions can be viewed like the cups within the cups. Consciousness comes into forms to provide as much as those forms can hold. Depending upon the dimension the consciousness is focused in, the ability to work within that level of understanding occurs. It is possible to expand consciousness within the human body, but it is limited based upon the current timeline, and the understanding that one has at that juncture. The beliefs limit one with what is possible. The third dimension is limited due to the physical limitations of that plane of existence. The fourth and fifth dimension are more fluent as consciousness flows through these forms like cups made of strainers. The third dimension is inside the fourth dimension, which is inside the fifth dimension, for example. The fifth dimension shares with the fourth dimension which shares with the third dimension. They are interconnected and the vibrational level of the third dimension depends upon how much the fourth dimension can provide to the third dimension.
The higher one vibrates, the more fluid one becomes for the conscious awareness of the other realms, or rather the other dimensions. There may be a day when you connect within the higher dimensions, and then the next day not be capable of connecting at all. It will be determined by your conscious efforts to bring this awareness into the forefront of your mind. You will need to clear the mind of any doubts of if they are real or not, and just go with the thought that you are a speck of sand in the big scheme of the universe. When viewing your world from the higher perspectives, you will be capable of seeing yourself from a mountaintop, and then from the stars. Once you grasp this concept , you will be capable of placing your conscious awareness into this perspective. Knowing the body is only temporary and energy cannot be destroyed, it only changes form, will bring you to an understanding that you carry your conscious awareness after the body has turned to the dust.
The higher realms touch the human thoughts like the waves that touch the feet when standing at the shoreline. It is your responsibility to allow the higher realms to enter into your life. The higher realms reach into the thoughts to not only help you learn and grow, it helps those in the higher realms utilize what they have learned so they can grow as well. All benefit from the expansion and those who are consciously dwelling in the fourth and fifth dimensions specifically are bound where they are until they master each level through service to others. The concept that we are all one is known in the higher levels, and they understand that to help those seeking specifically in the lower levels, provides them with a higher level of understanding for their own growth.