Two methods for teaching simple visual discriminations to learners with severe disabilities.

Area of Science:

• Behavioral Psychology
• Developmental Disabilities Research

Background:

• Simple discriminations are foundational for many functional skills and complex conditional discriminations.
• Individuals with severe disabilities often struggle with standard training methods like differential reinforcement for simple discriminations.

Purpose of the Study:

• To compare two errorless procedures for teaching simple discriminations to youths with severe disabilities.
• To investigate the effectiveness of stimulus control shaping versus progressive delayed prompting.

Main Methods:

• Employed multiple-probe designs to assess learning across three stimulus sets (photos and colored rectangles).
• Utilized differential reinforcement, progressive delayed prompt training, and stimulus control shaping with an adapted Wisconsin General Test Apparatus (WGTA).
• Manipulated stimulus orientation (flat vs. 45-degree angle) to assess its impact.

Main Results:

• Baseline and progressive delayed prompt training showed near-chance performance.
• Stimulus control shaping significantly increased accuracy for all stimulus pairs.
• Stimulus orientation was identified as a critical controlling variable, impacting performance.

Conclusions:

• Stimulus control shaping is a viable and effective errorless procedure for teaching simple discriminations to individuals with severe disabilities.
• The physical arrangement of stimuli, specifically their orientation, plays a crucial role in discrimination learning.