Claustrophobia not rational
Anyone with any strong fear or phobia knows, rationally, that their fear doesn't make sense. A person with a cat phobia, for example, knows that domestic cats are not truly dangerous. But they're still scared.
If you're claustrophobic, you know that other people can be perfectly comfortable in spaces that make you panic, but that knowledge makes no difference.
Why is that?
Because rational knowledge exists in a different part of the brain to the part that is creating the anxiety.
And that's where hypnosis comes in.