Abstract
In a phenomenon called ‘intentional binding’, the perceived temporal interval between a voluntary action (e.g., a button press) and a subsequent sensory event (typically 250 ms later) is subjectively compressed. We investigate this effect in light of recent work showing that perceptual sensitivity oscillates over time, exhibiting peaks and troughs, and that the phase of the perceptual oscillation is aligned with a voluntary action. We examined whether the ‘intentional binding’ effect oscillates over time after a voluntary action by measuring the effect with a fine-grained time course. Participants viewed a rotating clock-hand and voluntarily pressed a button to start a trial, after which a brief tone sounded at a random time (0–800 ms, in 5 ms steps). Participants reported the clock position when they heard the tone. The clock rotation period was either 2.5 s/cycle (Experiment 1) or 5 s/cycle (Experiment 2) and we measured the clock-reading error as a function of the time interval between the voluntary action and the tone. Consistent with previous ‘intentional binding’ results, both experiments showed that the perceived time of the tone (inferred from the clock position) was attracted towards the voluntary action. In general, the magnitude of ‘intentional binding’ decreased as the action/tone interval increased. Interestingly, the ‘intentional binding’ effect oscillated along this linear decreasing trend, oscillating at 1.8 Hz in Experiment 1 and 1.6 Hz in Experiment 2 within the time course of 800 ms. Our results suggest that the oscillations of ‘intentional binding’ may reflect the intrinsic dynamic modulation of attentional tracking which is not modulated by the speed of clock rotation.