RBT Task List – Skill Acquisition (C-10)

We’re steadily progressing through the crucial skill acquisition techniques in Section C. We’ve covered a lot of ground on how to teach existing responses or sequences of responses.

Now, we turn our attention to a powerful and often artful procedure used when the target behavior is not yet in the learner’s repertoire at all, or when we want to gradually change an existing behavior into a more refined or complex one.

Let’s dive deep into:

C-10: Implement Shaping Procedures

Shaping, also known by the descriptive phrase “the method of successive approximations,” is a delicate and highly effective application of differential reinforcement used to develop new behaviors or refine existing ones. It’s like being a behavioral sculptor!

What Exactly is Shaping?

Shaping is a behavioral procedure used to establish a novel target behavior that an individual does not currently exhibit. It’s achieved by systematically and differentially reinforcing successive approximations to that target behavior.

Here’s what that means in practice:

1. Initially, behaviors that only vaguely resemble the final target behavior are reinforced.
2. As the learner consistently emits these initial approximations, the criterion for reinforcement is gradually shifted only behaviors that are a closer approximation of the final desired behavior get reinforced.
3. Earlier, less accurate approximations are no longer reinforced (this is called putting them on extinction).
4. This process continues step-by-step until the individual is performing the complete target behavior.

Think of a sculptor working with a lump of clay. They don’t create the final, intricate form in one go. Instead, they make successive changes, gradually refining the clay, adding a bit here, smoothing a bit there, until the desired sculpture emerges. Shaping behavior works in a very similar, gradual fashion.

As an RBT, you’ll implement shaping procedures as they are designed and meticulously outlined by your supervising BCBA/BCaBA.

This task requires keen observation skills, precise timing of reinforcement, and the ability to adjust reinforcement criteria based on the learner’s performance, all while adhering to the supervisor’s plan.

When is Shaping the Go-To Procedure?

• When the target behavior is not currently in the learner’s repertoire (they don’t do it at all).
• When the target behavior is complex, and teaching it all at once is too difficult or overwhelming for the learner.
• To gradually change a specific dimension of an existing behavior (e.g., increase the duration of on-task behavior, improve the topography or form of handwriting, increase the volume of speech).
• When other teaching methods like prompting or chaining are not appropriate or have been ineffective for a specific target behavior.

The Core Components of Shaping: What Makes it Work?

• Differential Reinforcement: This is the absolute engine of shaping.
  • Definition: It involves reinforcing responses that meet a specific, pre-set criterion (which, in shaping, is a closer approximation to the target behavior) while withholding reinforcement (extinction) for responses that do not meet that criterion (such as earlier, less accurate approximations or other non-target behaviors).
  • How it works in shaping: The RBT selectively reinforces behaviors that are a step closer to the final goal and, crucially, stops reinforcing behaviors that were previously accepted but are no longer close enough.
• Successive Approximations:
  • Definition: These are a sequence of intermediate behaviors that gradually become more similar in form, frequency, duration, latency, or intensity to the ultimate target behavior.
    Each successive approximation acts as a stepping stone towards the final goal.
  • Identification: The BCBA will identify the starting behavior (something the learner already does that may be vaguely related or can be built upon) and the sequence of approximations leading to the terminal target behavior.
  • Example (Shaping the word “ball”):
    • Terminal Target: Learner says “ball” clearly.
    • Possible Successive Approximations:
      1. Any vocalization made by the learner when shown a ball (this could be the starting behavior).
      2. Vocalization starting with a /b/ sound (e.g., “buh”).
      3. Vocalization “bah.”
      4. Vocalization “bawl.”
      5. Vocalization “ball” (clear and correct pronunciation).
• Extinction (of previously reinforced approximations):
  • Definition: As the criterion for reinforcement shifts to a closer approximation of the target behavior, previously reinforced, less accurate approximations are no longer reinforced.
  • Why it’s crucial: If earlier approximations continue to receive reinforcement, the learner has no incentive to produce the closer approximations.
    Extinction of these older forms of the behavior helps “nudge” the behavior towards the new, more refined criterion.

Steps in Implementing a Shaping Procedure (Your Role as an RBT, Following the Supervisor’s Plan)

• Clearly Define the Terminal Target Behavior: You must have a crystal-clear understanding of the precise final behavior you are working towards, as defined by the BCBA.
• Identify a Starting Behavior: The BCBA will have identified an initial behavior that the learner currently emits and that has some relevance to the terminal behavior or can be shaped from.
• Identify the Steps (Successive Approximations): The BCBA will outline the intermediate steps. You must understand these steps and the criteria for moving from one to the next.
• Differentially Reinforce Successive Approximations:
  • Begin by reinforcing the starting behavior: Once the starting behavior occurs, the RBT begins to reinforce it consistently.
  • Shift criterion: When the starting behavior is occurring reliably, the RBT stops reinforcing it and only reinforces the next closest approximation from the planned steps.
    This requires careful observation to “catch” slight improvements or variations in the learner’s behavior that are closer to the next step.
  • Continue shifting: This process repeats. Each time an approximation is consistently emitted, reinforcement is withheld for that approximation, and only the next closer approximation is reinforced.
• Provide Immediate Reinforcement: When a response meeting the current criterion occurs, it must be reinforced immediately. The more immediate the reinforcement, the stronger the connection the learner makes.
• Monitor Progress Closely: RBTs must collect data on which approximations are occurring and being reinforced. This data helps the BCBA determine if the shaping steps are appropriate or if they need adjustment.
• Patience and Timing: Shaping can be a slow, incremental process. RBTs need patience and excellent timing to reinforce the desired approximations effectively. Rushing the process can lead to frustration for both the learner and the RBT.

Shaping in Action: Real-World Examples

• Shaping Vocalization Volume (Increasing Loudness):
  • Terminal Target: Client answers questions at an audible conversational volume.
  • Starting Behavior: Client consistently whispers responses.
  • Shaping Steps (Simplified):
    • RBT reinforces any whispered response (initial step).
    • RBT only reinforces whispers that are slightly louder than before (extinction for very soft whispers).
    • RBT only reinforces responses that are at a low conversational volume.
    • RBT only reinforces responses at a normal conversational volume.
  • RBT Action: During a conversation or DTT, if the client whispers an answer, and the current target is “slightly louder whisper,” the RBT reinforces.
    If they whisper too softly (below the current criterion), the RBT might look expectant or provide a gentle cue but not reinforce immediately, waiting for a slightly louder attempt.
• Shaping Duration of In-Seat Behavior:
  • Terminal Target: Client sits at a table for 10 minutes continuously during independent work.
  • Starting Behavior: Client currently only sits for approximately 30 seconds before getting up.
  • Shaping Steps (Simplified):
    • RBT reinforces sitting for 30 seconds.
    • RBT then only reinforces sitting for 45 seconds (extinction for 30-second sits).
    • Then only for 1 minute.
    • Then 1 min 30 sec, and so on, gradually increasing the duration criterion.
  • RBT Action: RBT uses a timer. If the current criterion is 1 minute, and the client sits for 1 minute, they receive reinforcement.
    If they get up at 50 seconds, no reinforcement is given for that instance of sitting (other procedures for getting them back to their seat would then apply).
• Shaping a Child to Tolerate Wearing Glasses:
  • Terminal Target: Child wears glasses for the entire school day.
  • Starting Behavior: Child immediately pulls glasses off when they are placed on their face.
  • Shaping Steps (Simplified):
    • RBT reinforces the child for just touching the glasses.
    • RBT reinforces holding the glasses.
    • RBT reinforces bringing the glasses towards their face.
    • RBT reinforces wearing glasses for 1 second.
    • RBT reinforces wearing glasses for 3 seconds, then 5s, 10s, 30s, 1min, etc., gradually increasing the duration.
  • RBT Action: RBT presents the glasses. If the child touches them, immediate praise and a highly preferred item are delivered.
    Next, only holding is reinforced, and so on. Highly preferred reinforcers are key for success in such programs.
• Shaping Handwriting (Improving Legibility of a Letter, e.g., “a”):
  • Terminal Target: Client writes a legible letter “a”.
  • Starting Behavior: Client makes a circular scribble when asked to write “a”.
  • Shaping Steps (Simplified):
    • RBT reinforces any circular mark.
    • RBT only reinforces circular marks that are more closed (less open).
    • RBT only reinforces closed circles that have a small line attempt on the side.
    • RBT only reinforces approximations that look more and more like a recognizable “a”.
  • RBT Action: During handwriting practice, the RBT provides praise/tokens for attempts that meet the current criterion for “closer to an ‘a’.”

Key Differences: Shaping vs. Prompting/Fading vs. Chaining

It’s crucial for RBTs to clearly distinguish shaping from other common behavioral procedures:

• Shaping vs. Prompting/Fading:
  • In shaping, the form of the behavior itself is gradually changed. The terminal behavior is not initially in the learner’s repertoire.
  • In prompting/fading, the terminal behavior is generally in the learner’s repertoire (or can be performed with assistance).
    Prompts are temporary assists used to evoke that known behavior, which are then systematically faded. The form of the target behavior doesn’t change through prompting; the level of assistance provided does.
• Shaping vs. Chaining:
  • In shaping, you are typically teaching a single behavior (though it can be a dimension of a behavior like duration or intensity) by reinforcing successive approximations of that one behavior.
  • In chaining, you are teaching a sequence of multiple, distinct behaviors that are often already in the learner’s repertoire (or are quickly taught via prompting).
    The focus is on linking these existing behaviors together in the correct order.

It’s important to note that sometimes these procedures can be combined. For example, you might shape one particularly difficult step within a behavior chain.

RBT Skills Crucial for Implementing Shaping Successfully

• Keen Observation: RBTs must be able to detect subtle variations in the learner’s behavior that are closer to the next planned approximation.
• Excellent Timing of Reinforcement: Reinforcement must be delivered immediately (within 1-2 seconds) when a desired approximation occurs to make the connection clear.
• Consistency with Differential Reinforcement: Diligently reinforcing only the current criterion and consistently withholding reinforcement for previous, less accurate approximations.
• Patience: Shaping can take time and many trials. Don’t get discouraged.
• Ability to “Think on Your Feet” (Within Supervisor’s Guidelines): While the steps are planned by the BCBA, sometimes a learner might emit a behavior that’s a good approximation but not exactly the planned next step. The RBT needs to be able to recognize this (and may need to consult the supervisor if it deviates too much from the plan).
• Avoiding “Over-Shaping” or “Under-Shaping”:
  • Under-shaping: Reinforcing an approximation too many times without raising the criterion, so the behavior gets “stuck” at that level.
  • Over-shaping: Raising the criterion too quickly, before the current approximation is stable, leading to a loss of the behavior (often called ratio strain) and potential frustration for the learner.
• Accurate Data Collection: Precisely recording which approximations are occurring and when criteria for reinforcement are shifted is vital for the BCBA to monitor progress and make adjustments.

Key Vocabulary for Shaping

• Shaping: Differentially reinforcing successive approximations to a terminal behavior.
• Successive Approximations: Intermediate behaviors that are closer and closer to the terminal behavior.
• Terminal Behavior: The final, desired form of the behavior.
• Starting Behavior (Initial Behavior): A behavior the learner already emits that has some relevance to the terminal behavior or can be built upon.
• Differential Reinforcement (in shaping): Reinforcing responses meeting the current criterion and extinguishing responses that do not.
• Extinction (of previous approximations): Withholding reinforcement for behaviors that were previously reinforced once a new, closer approximation is targeted.
• Topography (of behavior): The physical form or shape of a behavior. Shaping often changes the topography of a response.
• Dimensions of Behavior: Shaping can also target other dimensions like frequency (e.g., shaping more math problems completed), duration (e.g., shaping longer on-task time), latency (e.g., shaping quicker responses), or intensity/magnitude (e.g., shaping louder speech).

Common Pitfalls in Implementing Shaping

• Reinforcing Too Many Times at One Approximation (Under-Shaping): The learner gets “stuck” because there’s no incentive to try a closer approximation.
• Raising the Criterion Too Soon or Too Big a Step (Over-Shaping): The learner can’t meet the new criterion, the behavior may decrease (ratio strain), and they may become frustrated.
• Inconsistent Reinforcement: Not reliably reinforcing the current target approximation, making it hard for the learner to figure out what “works.”
• Poor Timing of Reinforcement: Delaying reinforcement, so the connection between the desired approximation and the reinforcer is weak or nonexistent.
• Drifting from the Terminal Goal: Getting sidetracked by reinforcing behaviors that are interesting or cute but not actually closer approximations to the planned terminal behavior.
• Giving Up Too Soon: Shaping can sometimes require many trials and significant patience.
• Not Recognizing Spontaneous Closer Approximations: Missing an opportunity when the learner emits a behavior that’s even better than the current target approximation. The RBT should be ready to reinforce these “leaps” (and consult the supervisor).
• Confusing Shaping with Prompting: Trying to physically prompt the next approximation instead of differentially reinforcing naturally emitted variations. While prompts can sometimes be used to help evoke an approximation in some shaping plans (as guided by the BCBA), the core of shaping is reinforcing existing variability that moves towards the target.

Shaping is a powerful and elegant procedure for building new behaviors from the ground up or refining existing ones.

It requires the RBT to be a precise observer and a skillful deliverer of reinforcement, always guided by the detailed plan from their supervisor.

This offers a very comprehensive look at C-10: Shaping Procedures. We’ve covered its definition, core components, implementation steps, key differences from other procedures, and common pitfalls.

Next in Section C is C-11: Implement token economy procedures. This is a common system used to manage and reinforce behaviors across various settings.