Action, prediction, and temporal awareness.

The brain needs to track changes in the relation between action and effect. In two experiments, participants made voluntary keypress actions. In an adaptation phase, these actions were followed after a fixed interval by a tone. During a subsequent test phase, the duration of the interval was unexpectedly changed. We used time perception as an implicit marker of the experience of participants' control over the effect, and confirmed a temporal binding between actions and effects. On test trials, participants perceived tones to occur as shifted towards their time of occurrence in the preceding adaptation phase. Therefore, the perceived time of a tone was partly based on learning of an internal prediction, rather than on the time of actual sensory input. This predictive model is rapidly updated over a few trials (Experiment 1), and requires attention to the tones (Experiment 2). The brain learns action-effect relations. This predictive learning influences the perception of effects, and underlies some temporal illusions associated with action.