Learning to stop or reset the internal clock

In the present experiments, after training rats in a standard fixed interval (FI) 30 s schedule, we induced a change in the strategy employed during gap trials, by presenting during FI with gaps training, 9-s interruptions of the FI discriminative stimulus in 40% of the trials; in one type of interruption, after the discriminative stimulus resumed, the FI was re-started; in the second type of interruption, the FI had to be completed considering the time before the interruption. The effect of these manipulations was tested in a peak-interval with gaps procedure. The main result was that the strategy employed during gap trials depended on the type of interruption experienced during the training phase, both in a comparison between subjects (experiment 1) and within subjects (experiment 2).

► During fixed interval training, gaps were presented for inducing rats either to stop or reset the internal clock.
► During gap procedure testing, rats behaved according to the training experienced.
► Timing behavior seems to be more flexible than what has been documented in the literature.