Lecture Notes on Stimulus and Stimulus Classes in ABA

Introduction

• Stimulus: The 'S' in the SRS (Stimulus-Response-Stimulus) Contingency
  • Related to ABC: Antecedent-Behavior-Consequence
  • Basis for operant behavior in Applied Behavior Analysis (ABA)

What is a Stimulus?

• A change in the environment that evokes a functional relation
• Examples include changes like noises, smells, lights, and people entering/leaving a room
• Behavior is a reaction to the environment, and the environment reacts back

Importance of Stimuli in ABA

• Stimulus control: Certain stimuli evoke specific behaviors
  • Example: Libraries evoke quiet, respectful behavior
• Stimuli are crucial in various ABA concepts such as:
  • SDs and S-deltas
  • Discrimination
  • Stimulus prompts

Types of Stimulus Classes

1. Physical (Formal or Feature) Stimulus Classes

   • Share common physical features (size, color, weight, spatial relation)
   • Help create concepts (e.g., dogs have tails, noses, paws)
   • Examples: Airplanes (wings, cockpit), Pizza (cheese, crust)

2. Functional Stimulus Classes

   • Based on behavior affected by the stimuli
   • Evokes or modifies behavior (e.g., antecedent and consequence in SRS)
   • Example: Music genres evoke dancing, stop signs evoke stopping

3. Arbitrary Stimulus Classes

   • Evoke the same response but do not share physical or formal similarity
   • Examples: Numbers (50, 1/2, etc.), Fruits (apple, banana) evoke the concept of fruit

Creating New Stimulus Classes

• Through stimulus-stimulus pairing
• Present two stimuli together to create a new stimulus class

Summary

• Stimulus: Changes in the environment affecting behavior
• Stimulus Classes: Can group by form, function, or arbitrarily
• Essential for understanding and applying ABA principles

Resources

• Visit bcbastudy.com for exam preparation materials and study guides.