Hello, I also have been wrestling with that question as I reboot but I think a trigger is like when my German shepherd see's me put on my sneakers she freaks out because she thinks I am taking her for a ride in my car or for a walk. Thus for my dog she associates my putting on my shoes with a rewarding stimulus. For us it is the same thing but our triggers would be seeing a commercial on T.V for example that is sexual in nature and it triggers the desire in us negatively to go and look at porn. I hope this helps.