Responses are polygamous. They are born wed to an unconditioned stimulus (US), and in that marriage adopt their partner’s surname, and so are known in that capacity the unconditioned response (UR). These are the instinctual, programmed stimulus-response relationships which are products of the evolution of the species rather than individual experience. They came along with your body.You didn’t learn how to get horny (UR) by looking at an attractive member of your preferred sex or sexes (US), after all, and evolutionary psychology suggests there are many more elaborate hardwired programs lurking beneath our notions of friendship, love and sexuality. We have all heard of fight-or-flight and playing opossum (URs), and those responses came along with your body, as did getting hungry (UR) in the presence of food (US).
This response can also marry a conditioned stimulus (CS), however, and in that role becomes known as the conditioned response (CR). In order for the response to do so, however, it must engage in a sufficient number of threesomes with the aforementioned stimuli. We call this classical conditioning, and it is the process by which we develop conditioned stimulus-response associations as habit patterns developed through individual experience.
Elicit UR by providing US paired with the desired CS to transform UR into CR for CS.
If for months you ring a bell (CS) right before you bring your dogs their dish of luscious meatiness, the salivating (UR) that the food (US) elicits will no longer merely be conjured by the food. Drool is now a two-timing sonuvabitch. The floodgates of saliva, while still an unconditioned response for the unconditioned stimulus of steak moosh, now responds equally well to the sound of the bell (CS) alone, with no food in evidence, consequently giving the drool an additional role as a conditioned response (CR).
Transmissions to Earth 