Shaping and Task Analysis in ABA

Shaping and task analysis are fundamental techniques in applied behavior analysis for teaching new skills. Shaping involves reinforcing successive approximations toward a target behavior, while task analysis breaks complex skills into smaller, teachable components. As an RBT, you’ll use these procedures to help clients acquire skills that might otherwise be difficult to teach.

Shaping

Shaping is a teaching procedure that involves reinforcing successive approximations of a target behavior until the final desired behavior is achieved.

The Concept of Successive Approximations

Successive approximations are behaviors that increasingly resemble the target behavior in topography (form) or function.

Examples of Successive Approximations:

For teaching “ball”: babbling → “ba” → “ba-l” → “ball”
For teaching hand-raising: looking at teacher → lifting hand slightly → raising hand partially → raising hand fully
For teaching writing: holding pencil → making marks → drawing lines → forming letters

The Shaping Process

1. Identify the Target Behavior

Define clearly: Specify exactly what the final behavior should look like
Ensure measurability: Make sure the behavior can be observed and measured
Consider functionality: Select behaviors that serve meaningful purposes
Assess current level: Determine what the learner can already do
Confirm appropriateness: Ensure the behavior is achievable for the learner

2. Identify the Starting Point

Current repertoire: Begin with a behavior the learner can already perform
Related response: Select a behavior that shares features with the target
Prerequisite skill: Choose a foundational behavior that can be built upon
Natural tendency: Start with a behavior that occurs spontaneously
Reinforceable response: Ensure the starting behavior can be reinforced

3. Define Successive Approximations

Break into steps: Identify incremental steps toward the target
Appropriate increments: Make steps small enough for success but large enough for progress
Observable changes: Ensure each approximation is distinguishable
Logical sequence: Arrange steps in developmental or logical order
Individualize: Adjust steps based on the learner’s abilities

4. Reinforce Each Approximation

Differential reinforcement: Reinforce closer approximations more strongly
Timing: Provide immediate reinforcement for successful approximations
Consistency: Reinforce each time the approximation occurs initially
Clear contingency: Ensure reinforcement is clearly linked to the behavior
Appropriate reinforcers: Use motivating reinforcers for the learner

5. Shift the Criterion

Timing: Move to next approximation when current step is consistent
Extinction: Stop reinforcing previous approximation when moving forward
Pace appropriately: Advance neither too quickly nor too slowly
Data-based decisions: Use performance data to guide criterion shifts
Prevent frustration: Balance challenge with success

6. Continue Until Target is Achieved

Persistence: Continue through all approximations to final behavior
Consistency: Ensure target behavior is performed reliably
Generalization: Promote performance across settings and situations
Maintenance: Plan for continued performance over time
Functional use: Ensure behavior serves its intended purpose

Example of Shaping: Teaching Vocal Requests

Target Behavior: Saying “I want [item], please” to request desired items

Starting Point: Reaching for desired items

Successive Approximations:

Looking at item and reaching
Making any vocalization while reaching
Approximating first sound of item name (“b” for “ball”)
Saying partial word (“ba” for “ball”)
Saying full item name (“ball”)
Saying “want ball”
Saying “I want ball”
Saying “I want ball, please”

Reinforcement Plan:

Initially reinforce reaching with item delivery
Then only reinforce reaching accompanied by vocalization
Gradually require closer approximations of target phrase
Provide more enthusiastic reinforcement for closer approximations
Eventually only reinforce complete target phrase

Advantages of Shaping

Teaches complex behaviors: Builds skills that couldn’t be taught all at once
Reduces frustration: Creates success at each step
Individualizes instruction: Can be tailored to each learner’s pace
Builds confidence: Provides reinforcement throughout learning process
Works with limited repertoires: Effective even with minimal starting skills
Naturalistic approach: Resembles how many skills develop naturally

Limitations of Shaping

Time-intensive: Can be a lengthy process for complex behaviors
Requires judgment: Decisions about when to shift criteria are subjective
Potential stagnation: Progress may plateau at intermediate steps
Reinforcer satiation: Extended shaping may lead to reinforcer effectiveness issues
Consistency challenges: Different implementers may reinforce differently
Data collection complexity: Tracking changing criteria can be challenging

When to Use Shaping

Shaping is most appropriate when:

The target behavior is not currently in the learner’s repertoire
The behavior is complex or difficult to teach through other methods
The learner has some foundational skills to build upon
Direct physical prompting is not feasible or appropriate
Gradual skill development is acceptable
The behavior can be broken into incremental steps

Task Analysis

Task analysis is the process of breaking a complex skill into smaller, teachable components that are sequenced in the order needed to complete the task.

Creating a Task Analysis

1. Select the Target Skill

Functional relevance: Choose skills that serve meaningful purposes
Developmental appropriateness: Select skills matching developmental level
Priority needs: Focus on high-priority skills for independence
Prerequisite assessment: Ensure foundational skills are present
Social validity: Consider importance to learner and stakeholders

2. Define the Boundaries

Starting point: Identify where the task begins
Ending point: Determine when the task is complete
Context: Consider where and when the skill will be performed
Materials needed: List all items required for the task
Participation level: Decide how independently the task should be performed

3. Identify the Steps

Methods for identifying steps:

Perform the task yourself: Complete the task while noting each step
Observe competent performer: Watch someone else complete the task
Consult existing analyses: Review established task analyses
Literature review: Research skill components in professional literature
Team collaboration: Work with others to identify steps

Guidelines for step identification:

Appropriate size: Make steps neither too large nor too small
Observable actions: Define steps in observable, measurable terms
Logical sequence: Arrange steps in order of performance
Completeness: Include all necessary steps
Clarity: Write steps clearly enough for consistent implementation

4. Validate the Analysis

Test the sequence: Try following the steps exactly as written
Check with others: Have colleagues review the analysis
Pilot test: Try teaching a learner using the analysis
Revise as needed: Modify based on testing results
Finalize: Document the validated task analysis

Types of Task Analyses

1. Sequential Task Analysis

Lists steps in the exact order they must be performed, with each step dependent on completion of previous steps.

Example: Hand washing

Turn on water
Wet hands
Apply soap
Rub hands together
Rinse hands
Turn off water
Get paper towel
Dry hands
Discard paper towel

2. Branching Task Analysis

Includes decision points where different actions may be taken based on specific conditions.

Example: Getting dressed based on weather

Check weather (decision point)
- If cold: Select warm clothes (go to step 2a)
- If warm: Select light clothes (go to step 2b) 2a. Put on long pants, long-sleeve shirt, sweater 2b. Put on shorts, short-sleeve shirt
Put on socks
Put on shoes
(If cold) Put on jacket

3. Hierarchical Task Analysis

Organizes steps into main components and sub-components in a hierarchical structure.

Example: Making a sandwich

Main task: Make sandwich
- Subtask 1: Gather ingredients
  - Get bread
  - Get filling
  - Get condiments
- Subtask 2: Prepare bread
  - Open bag
  - Take out slices
  - Place on plate
- Subtask 3: Add fillings
  - Apply condiments
  - Add main filling
  - Add optional toppings
- Subtask 4: Complete sandwich
  - Place second bread slice
  - Cut sandwich
  - Clean up

Factors Affecting Task Analysis

1. Learner Characteristics

Motor abilities: Physical capabilities affect step size and support needed
Cognitive skills: Processing and memory abilities influence step complexity
Sensory considerations: Visual, auditory, or tactile needs affect presentation
Attention span: Duration of focus impacts how many steps to teach at once
Learning history: Previous experience with similar tasks affects approach

2. Task Characteristics

Complexity: Number of steps and decision points
Linearity: Whether steps must follow exact sequence
Physical demands: Motor requirements of the task
Cognitive demands: Thinking, problem-solving, and memory requirements
Safety considerations: Potential risks that require special attention

3. Environmental Factors

Setting demands: Where the task will be performed
Available materials: Resources typically available
Time constraints: How quickly the task needs to be completed
Social context: Whether others are involved or present
Cultural considerations: Cultural expectations or variations

Using Task Analysis for Teaching

Once a task analysis is created, it can be used with various teaching procedures:

1. Chaining Procedures

Forward chaining: Teaching steps in sequence from first to last
Backward chaining: Teaching steps in reverse order, starting with the last step
Total task presentation: Teaching all steps in each session

2. Prompting Strategies

Most-to-least prompting: Starting with most intrusive prompts and fading
Least-to-most prompting: Starting with minimal prompts and adding as needed
Graduated guidance: Providing and fading physical guidance fluidly

3. Data Collection Methods

Total task approach: Recording performance on the entire sequence
Single opportunity method: Ending trial after first error
Multiple opportunity method: Prompting through errors to complete sequence
Step-by-step recording: Documenting performance on each component

Example Task Analysis: Tooth Brushing

Get toothbrush from holder
Remove toothpaste cap
Hold toothbrush in one hand
Pick up toothpaste with other hand
Squeeze small amount of toothpaste onto brush
Replace toothpaste cap
Put toothpaste down
Turn on water
Wet toothbrush
Turn off water
Brush front teeth (10 seconds)
Brush top teeth (10 seconds)
Brush bottom teeth (10 seconds)
Brush tongue (5 seconds)
Turn on water
Rinse toothbrush
Fill cup with water
Rinse mouth with water
Spit water into sink
Wipe mouth with towel
Turn off water
Return toothbrush to holder

Combining Shaping and Task Analysis

Shaping and task analysis are often used together for comprehensive skill development:

Complementary Approaches

Task analysis breaks down the sequence of a complex behavior
Shaping addresses the quality or topography of each step
Together they address both the “what to do” and “how to do it”

Implementation Strategies

Create detailed task analysis: Break skill into component steps
Identify current performance level: Determine which steps learner can do
Develop shaping plan for difficult steps: Create successive approximations for challenging components
Implement appropriate chaining procedure: Use forward chaining, backward chaining, or total task
Shape performance of each step: Reinforce increasingly accurate performance
Collect data on both acquisition and quality: Track both step completion and performance quality
Adjust as needed: Modify task analysis or shaping criteria based on progress

Example: Teaching Handwriting

Task Analysis for Writing Name:

Grasp pencil correctly
Position paper appropriately
Write first letter
Write second letter
Continue through all letters
Space letters appropriately
Stay on the line
Apply appropriate pressure

Shaping Plan for Step 1 (Pencil Grasp):

Holding pencil with fist
Holding with thumb and fingers (any grip)
Holding with thumb and first two fingers
Tripod grip with fingers too high
Proper tripod grip at appropriate position

Shaping Plan for Step 3-5 (Letter Formation):

Tracing over highlighted letters
Connecting dots to form letters
Copying letters with guide lines
Copying letters with starting point only
Independent letter formation

Practice Example

An RBT is working with a 7-year-old client with developmental delays on learning to tie shoes. The client can currently hold the laces but struggles with the motor sequence.

Question: How should the RBT approach this skill using task analysis and shaping?

Solution:

Task Analysis for Shoe Tying:

Cross left lace over right
Pull left lace under and through
Pull both laces to tighten
Make a loop with right lace (“bunny ear”)
Hold right loop with right hand
Wrap left lace around right loop
Push left lace through hole
Grab left lace that comes through hole
Pull both loops to tighten knot

Shaping Plan:

For steps with fine motor challenges (like steps 6-8), develop successive approximations:
- Initially accept loose, approximate movements
- Gradually shape toward more precise movements
- Reinforce increasingly accurate form
- Use physical guidance that gradually fades

Teaching Approach:

Use backward chaining (start with steps 8-9, with RBT doing steps 1-7)
Implement most-to-least prompting for each step
Provide visual supports (pictures or video modeling)
Use clear, consistent verbal cues
Shape motor movements within each step
Collect data on both step completion and quality of performance
Gradually fade support as performance improves

This combined approach addresses both the sequence of shoe tying (task analysis) and the quality of movement required for each step (shaping).

Key Points to Remember

Shaping involves reinforcing successive approximations toward a target behavior
Task analysis breaks complex skills into smaller, teachable components
Effective shaping requires clear definition of the target and systematic reinforcement
Task analyses should be validated and adjusted based on learner performance
Both techniques can be combined for comprehensive skill development
Individual characteristics affect how task analyses are created and implemented
Data collection is essential for monitoring progress and making adjustments
The ultimate goal is functional, independent performance of meaningful skills