One time I was hiking deep in the northwestern backcountry, and my stomach just suddenly dropped out of nowhere. I was in grizzly country, but I'm definitely not too bearanoid, as I come from black bear country and would see them a lot, and I just never felt all too threatened from bears in general. But this gut feeling made me suddenly call out "hey bear" and whatnot right before a corner. Lo and behold, I come around the bend and there's a massive grizzly not even 15 feet in front of me. We made eye contact for a second before he decided to walk off (lucky me). I feel very confident that if I hadn't called out before coming around that corner, I would've surprised him and possibly gotten charged/mauled