My bet: He was tested on down there and has also been partially, but not fully, reintegrated with the electric/magnetic field thing Asal first tried on Mark (or something similar). But due to all of the fragmented personalities (probably 20+ like Gemma) it didn't take. So now he has a lot of wires crossed in his head.

Bonus points: He's been like this the entire show. With his outtie personality being the only one experiencing visions (hence the paintings) due to the "bad" reintegration. That or his outtie personality isn't his real outtie and is just more Lumen fuckery.