Telepathic Silence

Creatures within the area cannot send or receive telepathic messages, and anyone in the area casting a spell with a thought component must succeed at a concentration check (DC = 20 + twice the spell’s level; this includes the increased concentration DC for casting spells with a thought component) or lose the spell. Furthermore, the thoughts of creatures within the area cannot be detected, located, or read with thoughtsense, detect thoughts, or similar effects.

Telepathic silence does not hinder spells that target a creature’s mind or that do not rely on communication, such as mind thrust.