A behavioral chain, also called a stimulus-response chain, is a consistent sequence of
stimuli and responses that occur closely to each other in time and in which the last
response is typically followed by reinforcement.
In a behavioral chain, each response produces a stimulus that serves as an S D for the next
response (and, as will be discussed later, a conditioned reinforcer for the previous
The stimulus-response connections are the "links" that hold the chain together.
if any response is so weak that it fails to be evoked by the S D preceding it, the next S D will
not be produced and the rest of the chain will not occur.
The reinforcer at the end of a chain maintains the stimuli in the chain as effective SDs for
the responses that follow them (and as will be described later, as effective conditioned
reinforcers for the responses that precede them).
not all behavioral sequences are behavioral chains.
It is not made up of a consistent series of stimuli and responses that occur closely in time
and for which each stimulus (except the last) is an S D for the next response.
METHODS FOR TEACHING A BEHAVIORAL CHAIN
The three major methods of teaching a behavioral chain are the total-task presentation
method, the backward-chaining method, and the forward-chaining method.
total-task presentation method, an individual attempts all of the steps from the
beginning to the end of the chain on each trial and continues with total task trials until that
person learns the chain
Prompting is provided at each step as needed, and a reinforcer follows the correct
completion of the last step.
Backward chaining gradually constructs the chain in a reverse order from that in which
the chain is performed. Backward chaining has been used in numerous programs, including
teaching various dressing, grooming, work, and verbal behaviors to individuals with
Thus, when one uses backward chaining, the reinforcement of the last step in the presence
of the appropriate stimulus, over trials, establishes that stimulus as a discriminative
stimulus for the last step and as a conditioned reinforcer for the next-to-last step.
Thus, the power of the positive reinforcer that is presented at the end of the chain is
transferred up the line to each S D as it is added to the chain.
1 theoretical advantage of always having a built-in conditioned reinforcer to strengthen each
new response that is added to the sequence.
The forward chaining method teaches the initial step of the sequence first, then teaches
and links together the first and second steps, then the first three steps, and so on until the
entire chain is acquired
At least partly because backward chaining resembles a reversal of the natural order of
things, forward chaining and total-task presentation are used more often in everyday
situations by individuals not trained in behavior modification.
total-task presentation has several practical ad- vantages over the other chaining formats
for teaching persons with developmental disabilities.
1. Total-task presentation requires the instructor to spend less time in partial
assembly or disassembly to prepare the task for training;
2. it appears to focus on teaching response topography and response sequence
simultaneously and, therefore, should produce results more quickly
3. it appears to maximize the learner's independence early in training, especially if
some steps are already familiar
individuals who do not have developmental disabilities-
For relatively simple tasks with a small number of steps, such as the preputt routine for
Steve, total-task presentation is probably the method of choice.
For more complex tasks, however, either backward or forward chaining is likely to be more
using backward chaining to teach certain tasks may be more practical- driving instructions,
CHAINING COMPARED WITH FADING AND SHAPING
Behavioral chaining, fading, and shaping are sometimes called gradual change procedures
be- cause each involves progressing gradually through a series of steps to produce a new
behavior, new stimulus