Hunter has an fmri and his doctor says that he notices that the gray matter has peaked in the lobe of his brain partially involved in dealing with higher-order thinking. the doctor is referring to what part of the brain

The appropriate response is Frontal lobe. The frontal lobe is the piece of the mind that controls vital subjective attitudes in people, for example, enthusiastic articulation, critical thinking, memory, dialect, judgment, and sexual conduct. It is, fundamentally, the "control board" of our identity and our capacity to impart.