Slide 1-11

Behavior exhibits variability, sometimes one behavior occurs; at other times, other behaviors occur.

We want to know why a behavior increases or decreases in rate or probability. We want to know why we do what we do.

Slide 1-12

A revolutionary advance occurred when it was realized that not only will some stimuli elicit reflexive responses, but a stimulus such a a bell, preceding that elicitor will result in the bell coming to elicit salivation.

This demonstration banished forever the belief that only humans could adapt to their environment, while lower animals were governed only by inborn instincts. Learning occurs across a very broad range of animals. This was a far more seminal realization than his other Nobel prize winning work.

If we kicked a desk it would move. If we first yelled "lookout" then kicked the desk, it would similarly move. Suppose we then simply yelled "lookout"--- if the desk moved ---we would be amazed by the miraculous event. We should be no less amazed by a dog (or a human) salivating to a bell; they are both also part of the natural world. The burning question is why do living things adapt and how?

Slide 1-13

Thorndike drew attention to an equally significant phenomenon. The consequence of a behavior affects the future rate of that behavior. If a person tells a joke and receives laughter, then it is more likely that that person will tell another joke.

Slide 1-14

Skinner went on to emphasize the importance of antecedent stimuli in the control of operant behavior. It is particularly likely that the person will tell the joke when with the same group, rather than when with a totally different group of people or only an empty room.

Additionally Skinner realized that the most productive way to conceptualize stimuli and responses was in terms of their commonality of function. All behaviors which covary as the result of the same environmental changes should be seen as being in the same class. Likewise all stimuli which have the same impact on behavior can most productively be seen as equivalent to each other.

Slide 1-15

The major functional relationships in short-term behavioral adaptation are conceptualized as:

a. If a response is followed by a reinforcer in the presence of some stimulus class, then it is more likely that that behavior class will occur when similar stimuli are in effect in the future.

b. If a stimulus precedes an elicitor, then it is more likely that similiar stimuli when presented in the future, will be followed by a reaction related to that controlled by the eliciting stimulus.

Slide 1-16

Terminology appropriate for describing causal functions in behavioral adaptation are:


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Date Last Reviewed : May 26, 2003