This week’s edition of the Step 1 Question of the Week is about psychiatry. See if you can answer the question and then watch the video to learn the correct answer as well as the rationales for each option.
A 21-year-old man is referred to a college psychiatric clinic after getting into many physical fights. He states that, as a child, he was always getting in trouble for misbehaving in class. He would think a thought and then act on it before he could stop himself. On physical examination, his knuckles look beaten and scarred, and he has bruises on his arms and face.
Which of the following neurotransmitters would most likely be decreased in this patient’s cerebrospinal fluid?