12.2 Teaching Simple and Conditional Discriminations

Board Certified Assistant Behavior Analyst BCaBA

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1 Introduction

About the BCaBA Exam: 2026 Format, Fees, Blueprint, and Study Plan

2 Chapter 1: Behaviorism and Philosophical Foundations

1.1 Goals of Behavior Analysis & Foundational Assumptions 1.2 Radical Behaviorism vs. Methodological Behaviorism & Rejection of Mentalism 1.3 Seven Dimensions of Applied Behavior Analysis & Branches of Behavior Analysis

3 Chapter 2: Core Behavioral Principles & Contingencies

2.1 Behavior, Response Classes, Stimulus Classes, and Conditioning Paradigms 2.2 Positive and Negative Reinforcement & Schedules of Reinforcement 2.3 Positive and Negative Punishment & Unwanted Effects of Aversives 2.4 Unconditioned, Conditioned, and Generalized Reinforcers and Punishers

4 Chapter 3: Operant Mechanisms & Complex Principles

3.1 Operant and Respondent Extinction Processes 3.2 Motivating Operations vs. Discriminative Stimuli 3.3 Stimulus Control, Equivalence, and Elementary Verbal Operants 3.4 Rule-Governed vs. Contingency-Shaped Behavior; Instructions, Rules, and Modeling

5 Chapter 4: Measurement Systems & Interobserver Agreement

4.1 Operational Definitions and Direct Continuous Measurement 4.2 Discontinuous Measurement Systems & Measurement Artifacts 4.3 Measurement Quality: Validity, Accuracy, Reliability, and IOA Calculations

6 Chapter 5: Data Display & Visual Analysis

5.1 Graphing Conventions: Line Graphs, Cumulative Records, and Standard Celeration Charts 5.2 Visual Analysis of Graphed Data: Level, Trend, Variability, and Immediacy of Effect 5.3 Baseline Logic and Data-Based Clinical Decision Making

7 Chapter 6: Experimental Design & Internal Validity

6.1 Characteristics of Single-Case Experimental Designs & Experimental Control 6.2 Core Single-Case Designs: Reversal, Multiple Baseline, Alternating Treatments, and Changing Criterion 6.3 Threats to Internal Validity & Social/External Validity

8 Chapter 7: Ethics in Behavior Analysis: Core Responsibilities & Client Rights

7.1 BACB Ethics Code Structure, Core Principles, and Professional Competence 7.2 Responsibility to Clients: Confidentiality, Informed Consent, and Client Dignity 7.3 Multiple Relationships, Conflicts of Interest, and Gift-Giving Prohibitions 7.4 Risks of Unethical Conduct, Public Statements, and Transitioning Clients and Supervisors

9 Chapter 8: Ethics in Assessment, Intervention, & Regulatory Compliance

8.1 Ethical Standards in Behavior Assessment and Intervention Selection 8.2 Mandated Reporting, Legal Obligations, and Documentation/Billing Integrity 8.3 Cultural Responsiveness, Interprofessional Collaboration, and Disciplinary Reporting 8.4 Interpersonal Skills for Professional Relationships and Ongoing Professional Development

10 Chapter 9: Behavioral Assessment & Functional Assessment

9.1 Indirect Assessment Methods and Review of Records 9.2 Descriptive Functional Behavior Assessment: Direct Observation and Data Collection 9.3 Experimental Functional Analysis (Analog FA) and Specialized Variations 9.4 Preference and Reinforcer Assessments & Social Validity 9.5 When Services Are Warranted, Skills Assessment, and Contextual Fit

11 Chapter 10: Foundational Behavior-Change Procedures

10.1 Differential Reinforcement Procedures (DRA, DRI, DRO, DRL, DRH) 10.2 Prompting Strategies, Prompt Hierarchies, and Systematic Prompt Fading 10.3 Shaping (Successive Approximations) and Chaining Procedures 10.4 Token Economies, Contingency Contracts, and Group Contingencies

12 Chapter 11: Antecedent & Function-Based Interventions

11.1 Functional Communication Training (FCT) and Noncontingent Reinforcement (NCR) 11.2 Antecedent Manipulations: High-Probability Sequences, Premack Principle, and Choice Architecture 11.3 Programming for Generalization and Maintenance: Stokes and Baer (1977) Tactics

13 Chapter 12: Teaching New Skills: Acquisition Arrangements, Discriminations, Verbal Behavior, and Self-Management

12.1 Discrete-Trial, Free-Operant, and Naturalistic Teaching Arrangements 12.2 Teaching Simple and Conditional Discriminations 12.3 Teaching Elementary Verbal Operants: Mands, Echoics, Tacts, and Intraverbals 12.4 Procedures That Promote Emergent Relations and Generative Performance 12.5 Self-Management Procedures

14 Chapter 13: Intervention Development, Fidelity, & Monitoring

13.1 Writing Socially Valid, Observable, and Measurable Behavioral Goals 13.2 Designing Behavior Support Plans: Function-Based Multi-Component Architecture 13.3 Treatment Integrity Monitoring, Fidelity Measurement, and Data-Based Plan Revision 13.4 Managing Behavioral Relapse, Transition Planning, and Systematic Discharge Criteria

15 Chapter 14: Supervisory Roles, Behavioral Skills Training, & BACB Requirements

14.1 The BCaBA Role: Practicing Under Ongoing BCBA Supervision and Professional Boundaries 14.2 Behavioral Skills Training (BST) for Direct Care Staff and RBTs 14.3 Objective Performance Monitoring, Performance Feedback, and Supervision Documentation 14.4 Promoting Cultural Humility, Equity, and Ethical Supervision in Behavioral Healthcare 14.5 Effective Supervisory Relationships: Practices, Expectations, and Supervision Goals 14.6 Performance Management, Performance Diagnostics (PDC-HS), and Evaluating Supervision

12.2 Teaching Simple and Conditional Discriminations

Key Takeaways Explain This Topic AI

A simple discrimination is taught by reinforcing a response in the presence of the SD and withholding reinforcement in the presence of S-deltas, which is differential reinforcement across stimuli.

A conditional discrimination, such as matching-to-sample or receptive identification, requires choosing a comparison according to the sample presented, so the learner must attend to the sample on every trial.

Prevent faulty stimulus control by counterbalancing comparison positions, rotating which stimulus is correct, removing unintended cues, and adding observing responses (Green, 2001; Grow & LeBlanc, 2013).

Teaching targets together in conditional-discrimination format from the start was more efficient than first teaching each target alone (Grow et al., 2011), and errorless procedures can reduce errors during acquisition.

Last updated: October 2026

From Stimulus Control to Teaching

Section 3.3 explained stimulus control as a principle. Task G.4 asks you to build it on purpose. Almost every academic and language skill is a discrimination: saying "red" only for red objects, reading "cat" only for the printed word cat , or handing over a spoon only when someone asks for a spoon.

Simple Discriminations

In a simple discrimination , one stimulus (the SD ) sets the occasion for reinforcement, and other stimuli ( S-deltas ) do not.

Teaching steps:

Present the SD and reinforce the target response.

Present S-deltas and withhold reinforcement for the same response (extinction), or reinforce a different response.

Alternate SD and S-delta trials unpredictably until responding occurs mainly in the presence of the SD.

Simple discriminations can be taught successively (one stimulus presented at a time, such as a light that is either on or off) or simultaneously (two or more stimuli present at once, and the learner selects one). Everyday examples include crossing the street only when the walk signal is lit and answering the phone only when it rings.

Conditional Discriminations

In a conditional discrimination , the correct response to a stimulus depends on another stimulus. The classic procedure is matching-to-sample (MTS) :

A sample stimulus is presented (a picture of a dog, or the spoken word "dog").

Several comparison stimuli are presented (pictures of a dog, a car, and a cup).

Selecting the comparison that goes with the sample is reinforced; which comparison is correct changes from trial to trial with the sample.

Identity matching uses physically identical stimuli (picture to picture). Arbitrary matching relates stimuli with no physical similarity (spoken "dog" to a dog picture; printed dog to the picture), which is the basis for language comprehension and for equivalence-based instruction (section 12.4).

Receptive identification ("Touch the cup") is a conditional discrimination with an auditory sample: the learner must listen to the instruction, then scan the comparisons. If the learner ignores the sample, they may still be correct by chance or by using an unintended cue.

Recommended Practices for Arrays

Research reviews of receptive and matching instruction (Green, 2001; Grow & LeBlanc, 2013) recommend:

Use arrays of at least three comparisons so chance accuracy stays low.

Counterbalance positions so each target appears equally often in each location.

Rotate the correct stimulus so each comparison is sometimes correct and sometimes an S-delta.

Present the sample in a consistent order relative to the comparisons and secure attention before presenting the SD.

Remove unintended cues : the instructor's gaze toward the correct card, a smudge on one card, a predictable left-right pattern, or always placing the newest item closest.

Add an observing response when samples are similar: having the learner touch, name, or echo the sample before choosing ensures they attend to it (a differential observing response).

Teach targets together in conditional format. Grow and colleagues (2011) compared the simple-conditional method (teaching each target alone first, then adding distractors) with the conditional-only method (teaching targets together in arrays from the start) and found the conditional-only method more efficient with fewer errors.

Errorless Discrimination Training

Errorless procedures arrange instruction so the learner rarely makes errors during acquisition:

Stimulus fading : make the correct comparison more salient at first (larger, brighter, closer), then fade the extra dimension.

Stimulus shaping : gradually change the form of the stimulus from an easy discrimination to the target one.

Prompt delay : begin with a 0-second delay (prompt delivered immediately), then insert a fixed or progressive delay so the learner can respond before the prompt.

Errorless procedures reduce frustration and error patterns, but probes without prompts are needed to confirm that the intended stimulus, not the prompt, controls responding.

Diagnosing Faulty Stimulus Control

Data pattern Likely problem Fix

Correct only when the target is in one position Position bias Counterbalance positions; reinforce only correct selections in other positions

Correct when the instructor looks at the target, not otherwise Instructor cue Neutral gaze, screen, or a second instructor

Selects the last reinforced item regardless of the sample Not attending to the sample (win-stay pattern) Rotate targets; add an observing response to the sample

Responds to one feature only (e.g., the color, not the shape) Stimulus overselectivity Teach with multiple exemplars that vary the irrelevant feature

High accuracy in teaching, low accuracy in natural settings Control by teaching materials Vary materials, settings, and instructors (train loosely)

Data and Mastery

Record accuracy per trial and review position and target patterns, not just overall percentage. A learner who is 66% correct in a three-item array might be correct on every trial in two positions and wrong in the third, which points to a position bias rather than slow learning. Use unprompted first-trial (cold) probes to judge mastery, and probe with new exemplars before calling a discrimination generalized.

Common Exam Traps

Calling receptive identification a simple discrimination. The correct choice depends on the spoken instruction, so it is conditional.

Using one-item "arrays." With only one comparison, the learner can be correct without discriminating anything.

Treating high percentages as proof. Always check for positional or instructor cues.

Assuming errorless means no testing. Prompt-free probes are required.