Errorless learning
Why the help fades instead of letting the child fail
What Interlaza does
Every concept starts with the wrong options barely visible — around 10% opacity — and they sharpen over three phases until the array is at full difficulty. A single error drops that concept back one phase immediately. Each concept carries its own phase, so a new word starts faint even when everything else in the same session is already running at full strength.
Why
An error is not a neutral data point. Terrace compared four ways of introducing the wrong option and found that introducing it early and faint produced between 2 and 9 errors during acquisition, while introducing it late and at full strength produced between 175 and 228. The count was not the interesting part. The subjects that learned through errors kept producing bursts of them long after the discrimination looked settled, responded faster but less reliably, and reacted to the incorrect stimulus as though it had become unpleasant. Errors leave a residue — in what gets learned, and in how the learner feels about sitting down to the task tomorrow.
Terrace never claimed that error-free teaching is always the better trade, and neither do we. Reviewing 46 experiments, Cengher and colleagues found that the class of help Interlaza uses — built into the display itself rather than added on top of it — was more effective than the alternatives in 14 of the 15 studies that compared the two. But they also found that a procedure which tolerates a couple of errors won its own comparisons. Minimising errors is one measure of efficiency among several, and which one matters depends on the learner in front of you. It is our default, not a law.
What it rests on
- Terrace, H. S. (1963). Discrimination learning with and without "errors". Journal of the Experimental Analysis of Behavior, 6(1), 1–27.
- Cengher, M., Budd, A., Farrell, N., & Fienup, D. M. (2018). A review of prompt-fading procedures. Journal of Developmental and Physical Disabilities, 30, 155–173.
- Green, G. (2001). Behavior analytic instruction for learners with autism: Advances in stimulus control technology. Focus on Autism and Other Developmental Disabilities, 16(2), 72–85.