Saunders Kathryn J, Hine Kathleen, Hayashi Yusuke, Williams Dean C
University of Kansas, Life Span Institute, Lawrence, KS USA.
Division of Social Sciences and Education, Pennsylvania State University, Hazleton, 76 University Drive, Hazleton, PA 18202 USA.
Behav Anal Pract. 2016 Jun 17;9(3):223-9. doi: 10.1007/s40617-016-0131-2. eCollection 2016 Sep.
Persistent error patterns sometimes develop when teaching new discriminations. These patterns can be adventitiously reinforced, especially during long periods of chance-level responding (including baseline). Such behaviors can interfere with learning a new discrimination. They can also disrupt already learned discriminations, if they re-emerge during teaching procedures that generate errors. We present an example of this process. Our goal was to teach a boy with intellectual disabilities to touch one of two shapes on a computer screen (in technical terms, a simple simultaneous discrimination). We used a size-fading procedure. The correct stimulus was at full size, and the incorrect-stimulus size increased in increments of 10 %. Performance was nearly error free up to and including 60 % of full size. In a probe session with the incorrect stimulus at full size, however, accuracy plummeted. Also, a pattern of switching between choices, which apparently had been established in classroom instruction, re-emerged. The switching pattern interfered with already-learned discriminations. Despite having previously mastered a fading step with the incorrect stimulus up to 60 %, we were unable to maintain consistently high accuracy beyond 20 % of full size. We refined the teaching program such that fading was done in smaller steps (5 %), and decisions to "step back" to a smaller incorrect stimulus were made after every 5-instead of 20-trials. Errors were rare, switching behavior stopped, and he mastered the discrimination. This is a practical example of the importance of designing instruction that prevents adventitious reinforcement of maladaptive discriminated response patterns by reducing errors during acquisition.
在教授新的辨别能力时，有时会出现持续的错误模式。这些模式可能会被偶然强化，尤其是在长时间的随机水平反应期间（包括基线期）。此类行为会干扰新辨别能力的学习。如果它们在产生错误的教学过程中再次出现，还会破坏已经学会的辨别能力。我们给出一个这一过程的例子。我们的目标是教一名智障男孩在电脑屏幕上触摸两个形状中的一个（用专业术语来说，是一种简单的同时性辨别任务）。我们使用了大小渐变程序。正确刺激物是全尺寸的，错误刺激物的尺寸以10%的增量增加。在达到并包括全尺寸的60%之前，表现几乎没有错误。然而，在一次对全尺寸错误刺激物的探测测试中，准确率大幅下降。此外，一种在课堂教学中显然已经形成的在两个选择之间切换的模式再次出现。这种切换模式干扰了已经学会的辨别能力。尽管此前已经掌握了将错误刺激物渐变到60%的步骤，但在超过全尺寸的20%之后，我们无法始终保持高准确率。我们改进了教学程序，使渐变以更小的步骤（5%）进行，并且在每5次而不是20次试验后做出“退回”到更小错误刺激物的决定。错误很少出现，切换行为停止，他掌握了辨别任务。这是一个实际例子，说明了设计教学时防止通过减少习得过程中的错误来偶然强化适应不良的辨别反应模式的重要性。
