You can describe the profession in many ways: "cat therapist", "cat behavior therapist", "cat behaviorist", "cat psychologist" or perhaps the most famous term "cat whisperer".
However, it all comes down to observing the behavior, trying to understand it and trying to adjust to more desirable behavior. Everything is based on the natural behavior of the cat, founded on professional literature.
Please take a look at "Behavioral Therapy for Cats".