Chaining
Learning Activities (Use hyperlink to view activity worksheets.)
1. Definitions 2. Identify concepts from animal acts (Refer to the Vending Chicken.) 3. Provide your own examples 4. Crossword puzzle 5. Word search
	Chaining
Click to View Postcard Vending Chicken in Action!	Chaining is the process of connecting a series of smaller behaviors to form a relatively long sequence of activity (a "chain"). After training, only the last behavior in the sequence is followed by a reinforcer. In the Postcard Vending Chicken, the customer would deposit a coin in the coin slot, which would turn on a small light in the cage next to a loop on the side of the cage. After this light came on, the chicken would pull the loop (turning on a "Thank You" sign). This pull of the loop would also trigger a second light next to an upright lever towards the front of the cage. After the second light came on, the chicken would then pull on the lever towards the front of the cage. This pull would be reinforced by the sound of the feeder and the delivery of grain. In short, there were two behaviors in the chain: pulling the loop    pulling the lever Further, the first behavior (pulling the loop) was reinforced by a conditioned reinforcer (that is, the second light coming on). In turn, this conditioned reinforcer then served as the discriminative stimulus for the second behavior (pulling the lever). The behavior of pulling was reinforced by the delivery of grain (and the  sound of the feeder). The chain went like this:      SD (light 1) + pull -> S+ (light 2)                                    SD (light 2) + pull -> S+ (sound of feeder) and S+ (grain)
	Backward Chaining
Click to View Home Run Chicken in Action!	In the process of backward chaining, the animal learns the last behavior in the sequence first, then the next-to-last behavior, etc. In this way, the entire sequence of behaviors is learned, although the instruction starts with teaching the last behavior first. For example, in the Home Run Chicken, the chicken was first placed directly onto third base and taught to run from third base to home plate (stepping on home plate was reinforced with grain).  After the behavior of going from third base to home was well established, the chicken was placed on second plate - and then  running to third, then home, was reinforced. In this way, the bird could eventually be taught to run from home to first, to second, to third, and then back to home in a "chain."
	Forward Chaining
	In the process of forward chaining, the animal learns the first behavior in the sequence, then the second behavior in the sequence, etc. If the Home Run Chicken had been taught with forward chaining, it would have been taught first to run from home plate to first base, and then from home plate to first and then to second, etc. In other words, the steps are trained in the same sequence as they occur in the actual performance. (However, recall that the Home Run Chicken was taught with backward chaining, which is usually the better method for teaching a long sequence to animals.)