The neurotransmitter ________ is thought to play a significant role in the brain's reward system that is involved in the learning processes of both humans and animals

One of the reasons that more research studies are conducted using questionnaires than using interviews is that

a. questionnaires are more valid than interviews. b. interviews are not as reliable as questionnaires. c. coding interview data takes considerable time, effort, and money. d. questionnaire data is the most likely to be generalizable.

People diagnosed as having hoarding disorder or body dysmorphic disorder likely had a relative with

a) OCD. b) social anxiety disorder. c) mood disorder. d) identity disorder.