Aliens? #2

Say extraterrestrials do exist and they are unlike anything humans have ever seen. Do you think you'd be able to control your flight or fight reflex? I've tested this out myself with insects that are repulsive to me and it seems to be very difficult. If the insect comes near me, I want to run, I also have the simultaneous reflex to kill it. I really don't know how I would react if an extraterrestrial tried to approach me but I doubt it would be positive. What do you think?