Module 4 - Chap. 20: Chaining Flashcards
Definition of a behavior chain
A specific sequence of discrete responses
Each associated with a particular stimulus condition
When components are linked together, they form a chain that produces a terminal outcome
Components in Chain Serve Dual Functions
Each response in the chain serves as a conditioned reinforcer for the response that produced it
Each response in the chain serves as a discriminative stimulus for the next response in the chain
Exceptions: the first & last responses in the chain
Behavior Chains & Limited Hold
A sequence of behaviors that must be performed correctly & within a specified time to produce reinforcement
Emphasizes both accuracy & proficiency
Characteristics of behavior chains
A series of discrete responses
Performance of behavior changes the environment such that it produces conditioned reinforcement for previous response & serves as S^D for next response
Behaviors must occur in sequence & in close temporal succession
Rationale for Chaining
Teaches complex skills that allow individuals to function more independently
A way to add new behaviors to an existing behavioral repertoire
Can easily be combined with other procedures (prompting, instruction, reinforcement)
Task Analysis
Breaking a complex skill or series of behaviors into smaller, teachable units
The product of a task analysis is a series of sequentially ordered steps
Constructing a Task Analysis
Notes:
- Sequence one individual may use to perform skill may not be the same as another individual
- Must be individualized according to
- Age
- Skill level
- Disability
- Prior experience
- Some task analyses have a limited # of steps, but these steps may be broken down into subtasks
Constructing a Task Analysis METHODS
Observe a competent individual perform the task
Consult with experts or persons skilled in performing the task
Perform the task yourself
Can refine as you use it, if necessary
Assessing Mastery Levels
Single- opportunity method:
- Give cue to begin task
- Record learner performance with + or - for each step
- Assessment stops as soon as a step is performed incorrectly
- Remaining steps are scored with a -
Assessing Mastery Levels
MULTIPLE-OPPORTUNITY METHOD
- Give cue to begin task
- Record learner performance with + or - for each step
- If a step is performed incorrectly, the trainer completes that step for the learner
- Learner continues to next step
- Do NOT co-mingle teaching with assessment
Single vs Multiple Method
Single
- More conservative
- Gives less information
- Quicker to conduct
- Reduces likelihood of learning taking place during assessment
Multiple
- Takes more time to complete
- Provides trainer with more information
- May make training more efficient by allowing trainer to eliminate instruction on already-learned steps
Behavior chaining procedures
Forward chaining:
- Training begins the link with the first behavior in the sequence
- Training only occurs on the steps previously mastered & current step (no training on steps after that)
Advantages = can be used to link smaller chains to larger ones, relatively easy
Total-task chaining
Training is provided for every behavior in the sequence during every training session
Trainer assistance (prompting) is provided on every step
Backward chaining
Training begins the link with the last behavior in the sequence
Trainer performs all by last step until learner masters last step
Then trainer performs all but last two steps until learner masters last two steps, and so on…
Advantages = natural reinforcement is produced immediately upon the learner’s response; learner contacts these natural contingencies of reinforcement on every learning trial
Backward chaining with leap aheads
Follows same procedures as backward chaining, but not every step in the task analysis is trained
Other steps are probed
If some steps are in learner’s repertoire, they are not taught
The learner is still required to perform those steps, however
Which procedure to use?
No data to indicate one is more effective than another
Choose total-task chaining if:
- learner knows many of the tasks but needs to learn how to do them in sequence
- has an imitative repertoire
- has moderate to severe disabilities
- task is not long or complex
Behavior chain interruption strategy (BCIS)
Chain is interrupted at a predetermined step so that another behavior can be emitted
Interruption may cause some distress
- It momentarily blocks access to reinforcement
This is somewhat desirable because it creates motivation to learn the new behavior in the chain
- As long as it is not so distressful that it causes emotional responding or self-injurious behavior
BCIS
Collect baseline data
Direct person to start chain
At predetermined point, restrict learner’s ability to complete next step
Prompt learner to engage in new targeted step
Then allow the individual to proceed with the chain
Breaking Inappropriate Chains
Determine initial S^D &
- Substitute an alternative, or extend chain & build in time delays within the chain
Examine potential sources of difficult in the chain
Breaking Inappropriate Chains (cont.)
Examining potential sources of difficulty
- Re-examine S^Ds & responses (is the sequence arbitrary? would rearranging sequence help?)
Determine whether similar S^Ds cue different responses
- If so, can the sequence be rearranged to separate the two similar S^Ds?
Analyze the job setting to identify relevant & irrelevant S^Ds
Do you need to implement discrimination training so that the learner can discriminate the relevant from irrelevant S^Ds?
Determine whether S^Ds in the job setting differ from training S^Ds
- May need to conduct some training in job setting
Identify presence of novel stimuli in the environment
Discrimination training might be necessary to teach the learner to ignore novel, irrelevant stimuli
Factors Affecting Performance
Completeness of the task analysis
- More complete, detailed task analyses tend to produce better learning
- Time developing task analyses is well spent
- Be ready/willing to modify it after it is constructed
Length/complexity of chain
- Longer chains take more time to learn
Factors affecting performance: Schedule of reinforcement
Must use appropriate schedule
Consider # of responses in chain when determining the schedule
Factors affecting performance: Extinction
Responses performed further from the reinforcer may become less likely
This interrupts the S^D relation & can result in withering performance of the chain
Lesson: adjust reinforcement schedule according (use intermittent schedules)
Factors affecting performance: Stimulus variation
Introduce all variations of the stimulus items to be encountered later to increase generalization of the chain
Factors affecting performance: Response variation
Varied responses may be needed to deal with stimulus variation
This may require some retraining of responses
