Its called a psychological obstruction. Physical manifestation of a mental conflict. These people "scare" you into thinking that what you are doing can only have negative consequences . In response your brain begins to release a certain chemical that make you feel queasy and unsure of everything. This is a safety feature in the brain to keep you out of harm way whether precieved or real. If you really want to continue researching these subjects then you will have to learn some form of mind over body control. This will also elevate your total awarness and be able to decern the truth better from mere fantasy.