How do/should horror checks work in relation to outdoor tiles?

My instincts say that as long as a monster stays within line of sight to any particular investigator, that investigator should only have to take a horror check when the monster first appears. Should the investigator lose LOS to the monster, and then subsequently regain it, then another check would be in order.

Does this sound right/in line with the rules?

Thanks for your time...

Different tiles count as different "room"s, as do different named delineated areas. It's best just to remember that LoS isn't quite good enough: the investigator makes a horror check whenever he enters a new room with a monster in it, or whenever the monster newly enters his room. This might mean that between an outdoor LoS, the monster has multiple opportunities of performing a horror check, especially if the investigator is moving between these "room"s a lot. Thematically, the investigator is becoming terrified that the monster is chasing him across such lengths.

Also if your username is a reference to Aliens then I'm thrilled. If it's actually your name then ignore that last comment.