I've noticed several of them around the Academy. I dismissed it at first because a lot of people are clustered there, all with different powers, and that can make it hard for me to discern what I'm seeing, but then I saw the same thing popping up farther away. Distance is a little.. strange when I'm looking at the world that way, but I'm reasonably certain I saw something in the neighborhood of your brother's house a few days after you arrived.
I've tried looking at people who I know have been affected, but there's nothing strange about their energy. They look like people.