Ghosts and the Physiological Response to Fear
In my research, I found that the body feels fear before the mind can process it. That means that if I expose you to some stimuli which your find frightening, your heart rate will increase before you can cognitively tell me that you are afraid. Our awareness of fear is based on our physiological reactivity and not vice versa. This is why panic attacks are so difficult to treat psychotherapeutically without drugs. The body has learned to be afraid of an irrational stimulus and will react before the mind can tell it that the fear it is having is irrational. In order to treat panic disorder, the body has to be retrained, not the mind. Exposure therapy is a way of doing this slowly over time and Submersion therapy or flooding is the fast and difficult way of doing this.
For me this is interesting for ghost hunters and paranormal enthusiasts, because we often say we feel something. We say that we feel a presence. That feeling is not rational. We don't think about it. We just know something is there and that produces a fear response. I believe this is a physiological response to something that our normal senses can't perceive but that our body is aware of. Perhaps our sympathetic nervous system is able to sense something that we are not cognitively aware of and this produces a feeling even when there is nothing we can see with our senses. Cognitively, we aren't aware of anything scary. But our body feels that fear. Our body knows there is something there even though we can't see it. The fear fealing in the presence of the supernatural is an adaptive response to an unpercievable stimulus.