Speeding up a master clock common to time, number and length?

The present study investigated the effect of a click train on the bisection of time, number and length when each modality was presented sequentially and non-sequentially. For the bisection of time, the results showed that the clicks shifted the bisection function toward the left and decreased the bisection point (point of subjective equality), thus suggesting that the stimulus duration was judged longer with than without clicks, and this is both in the sequential and the non-sequential condition. For the bisection of number and length, the click train again produced a leftward shift of the bisection function with the result that the number was judged greater and the line longer with than without clicks, but only when the number and the length were presented sequentially. This suggests that the click-related lengthening effect is not due to speeding up of an internal clock specifically devoted to the processing of time, but rather to an effect acting on an accumulator process that is commonly mobilized when judging the magnitude of quantities presented sequentially.