Sigmund freud pioneered the behavioral approach to psychology with his study on how dogs learned to have a biological responses (salivation) to a learned stimuli (bell).

answer; primary source information;

an informal structure in a bureaucracy would be something like so-called "office politics". where there's a formal structure set up for the organization, but then an informal subculture as well that has a way of organizing the bureaucracy further. this can be positive because it sets up an added degree of organization, albeit informal, within the bureaucracy.