lagmer: No just started a new chapter, had in in the last also. its like its some sort of mutation effect or such, buts its really getting annoying. Didnt have it the first many hours when i started playing the game in the beginning. Must be some ability/mutagen thing.
*EDIT*
Started a new game and maxed out my abilities, no screen effect.
Have some mutagens and runes in old game will check it out.
Did you ever determine what causes the effect? I thought it was from being under the influence of potions for too long but I was never sure.