Insight problem solving is characterized by restructuring. We hypothesized that the difficulty of rebus puzzles could be manipulated by systematically varying the restructurings required to solve them. An experiment using rebus puzzles varied the number of restructurings (one or two) required to solve a problem and the level at which the restructuring took place (sub-word level, word level, and supra-word level). Solution rates were higher for one restructuring than two, and higher for restructuring at the supra-word level (relation between words) than at lower levels. To explain the findings, we suggest that rebus puzzles initially engage normal reading processes, which involve extracting meaning at the level of relations between words.
MacGregor, James N. and Cunningham, John B.
"The Effects of Number and Level of Restructuring in Insight Problem Solving,"
The Journal of Problem Solving:
2, Article 7.