Agoraphobia:

Agoraphobia is of the negative traits.
It has a value of -5

The description is as follows:

Agoraphobia:
Maybe you grew up in a Vault or a similarly confined space, maybe you had some special kind of trauma: either way, you don't just feel funny when you're outside, you get sick and have panic attacks.
As soon as you see a true horizon, every test on perception and intelligence as well as on any skill that (according to the master) requires concentration is heavily penalized.
Please make out the details with the master.