The deep comprehension of a text is tantamount to the construction of an articulated mental model of that text. The number of correct recollections is an index of a learner's mental model of a text. We assume that another index of comprehension is the timing of the gestures produced during text recall; gestures are simultaneous with speech when the learner has built an articulated mental model of the text, whereas they anticipate the speech when the learner has built a less (...) articulated mental model. The results of four experiments confirm the predictions deriving from our assumptions for both children and adults. Provided that the recollections are correct, the timing of gestures can differ and can be considered a further measure of the quality of the mental model, beyond the number of correct recollections. (shrink)