Final answer:
B.F. Skinner is the psychologist known for going by his initials, a behaviorist who focused on observable behavior and developed the operant conditioning chamber.
Step-by-step explanation:
The psychologist whose first name began with 'Burrhus' and typically went by his initials was B.F. Skinner. Skinner was a renowned American psychologist and a leading figure in the school of thought known as behaviorism. Unlike other psychologists who focused on inner experiences, behaviorists like Skinner concentrated on observable behavior and its modification through reinforcement and punishment. Skinner's legacy includes the development of the operant conditioning chamber, also known as the Skinner box, which allows for detailed study of behavioral changes in response to various stimuli.