Why don’t we laugh when we tickle ourselves?

When we are tickled, we laugh and wriggle. This is what is termed a reflex action, an action which takes place without any thought on our part.

Balancing ourselves when we walk is another example of reflex action.

We retain our balance automatically, without thinking about it, but when we try to tickle ourselves, the brain knows that we are going to do it and so there is no reflex action.