Thaddeus volunteers behind the scenes at the local community theater. While setting up for a show, another volunteer accidently dropped a heavy set piece on Thaddeus's head. For several months after the accident, Thaddeus had significant trouble with problem solving, weighing multiple solutions, and forming strategies. Fortunately, Thaddeus recovered most of his functioning, although at times he still has minor trouble with these skills. It is MOST likely that the accident affected Thaddeus's _____ lobe.