You can read the full document here: https://www.cia.gov/library/readingroom/docs/CIA-RDP96-00788R001700210016-5.pdf
For conventional science, the idea that we can get out of the body is not only far from being proven as it sounds absurd. After all, science does not believe in spirits. It does not accept the idea of an essence living within our body so it can not even imagine that it is possible to separate from the other.
According to the scientific model, we are our body: our essence, inseparable from us, is within our cells, especially in the brain. It is precisely in the brain the explanation of the scientists for this phenomenon and it is very prosaic, almost disappointing. There are those who believe, however, that the human being is able to detach himself from his body during sleep, to move through walls, to travel distances at unthinkable velocities, to interact with others who are in the same state or even with those already died.