Sleep Paralysis

First of all, I do not believe that this type of experience is caused by any demonic being, or at least, not as a major cause. I can provide a few answers to the usual questions.

The entire phenomena occurs during REM sleep, which is the last stage of sleep. During REM sleep, one's awareness increases and the sleeper starts dreaming. However, due to the fact he would not know he was dreaming, he would act out of his dream, similar to somnambulism. I'll discuss about that too. Therefore, in order to prevent this from happening, REM antonia comes in. This means that all the muscles connected to the bone get paralyzed so that we cannot move while dreaming. Now, since awareness is increasing, there's a way of someone getting aware of REM antonia. This process is called Sleep paralysis. In this state many auditory, visual and other types of hallucinations can occur.

Visual hallucinations
There are many types of visual hallucinations. However, I have not experienced many, but I shall talk about the usual ones. Mostly, people get in this state the feeling of fear, as they are incapable of moving and maybe speaking. Some of them may even perceive a presence in their room. This fear, apparently, is the first thing that can come into your mind when this process occurs. It has happened to me also. The presence of a being is said to occur only because the sleeper perceives his paralyzed body. However, the solution I have gotten for this is to not expect any presence and call it only a hallucination when it occurs. The fact that this makes them go away proves that they are harmless.

Auditory hallucinations
These types of hallucinations, according to my own personal experience, occur more often than the visual ones. You can experience loud vibrations, whispers, even your name being called. Unfortunately, I am not capable of explaining the vibrations that occur, however, once you separate form the body, they wear off. You do not even remember you've had them; they just vanish. These vibrations can be perceived also as your name or as whispers. It has recently happened to me, however, when I wished them away, all I had to do was to say it. In other words, do not worry much about these either, since they are only hallucinations that can be wipped off.

Other types of hallucinations / issues
One issue, that apparently, everyone is experiencing is breathing problems. I have had this issue too at the very beginning of my journey, however, with time and research I’ve realized that it isn't me not breathing enough, it is me who is the problem. While we are awake, breathing, we are using our intercostal muscles, however during sleep, we get into an "automatic breathing pattern". Therefore, once we get in REM sleep, muscles get paralyzed, yet, we are still breathing. Once we get aware of this process we try to breathe as we are used to, but since we cannot move any muscles at all, we get the feeling of not breathing enough or suffocation. If you go consciously in the state, with the intent of separation, you will forget to worry about your breath and just continue what you have planned. This breathing issue also explains the pressure some people have on their chest. It is not a being, it is only you inducing it.

Causes
Since this process occurs in REM sleep, this is where we need to go.

- Needs to be continued -

However, if you check out the methods I have on my blog, you may figure out what the causes actually are.