The relationship of delay of gratification and time comprehension in 4-year-old children

In a typical delay-of-gratification task, children have the choice between eating a small amount of treats immediately and waiting in order to receive a larger number of treats. To date, it has not been investigated whether children's time comprehension is related to the ability to wait for the larger number of treats. Time comprehension can be tested by presenting children with three hourglasses containing different amounts of sand and asking them about the running time of the hourglasses (e.g., Which hourglass will finish first?). In this study, 75 four-year-old children were tested with a delay-of-gratification task, a time comprehension task, and a receptive language task. Children who ate the treat immediately in the delay-of-gratification task did not perform above chance level in the time comprehension task. In contrast, children who waited in the delay-of-gratification task, either for some time or until the end of the task, did perform above chance level. Correlation analyses revealed that performance in the time comprehension task and in the delay-of-gratification task correlated even after controlling for receptive language ability. Thus, children's time comprehension is related to their ability to delay a prepotent response. The nature of this correlation is discussed.