In this specific work participants

In this specific work participants enumerated objects. The objects were arranged either in a symmetrical and well known configurations (the so called canonical patterns) or in a random pattern. Additionally, we used two further arrangements: slightly and strongly distorted canonical patterns. Participants could subitize sets with more than four objects if they were arranged canonically. Furthermore, the more noisy the patterns were, the less likely the participants could subitize them. These results are consistent with the ideas that (1) subitizing is pattern recognition, and (2) pattern recognition system is flexible enough to transfer any pattern of less than five objects to a known pattern, but beyond four this ability is limited.