M LLER LYER ILLUSION FEEDBACK VERSUS NO FEEDBACK
The Harris and Slotnick (1996) reported that feedback can improve performance on a wide variety of tasks including tests for visual illusions. In contrast, no feedback would be presumed as a negative enforcer, leaving subjects with little or no knowledge of improvement. But it is possible that subjects are able to improve throughout repeated trials, without any feedback. Harris and Slotnick (1996) found that “feedback can enhance or accelerate” changes in measurement results, reducing the visual illusion in the subject’s eye.