Comparison of flashed and moving probes in the flash-lag effect: evidence for misbinding of abrupt and continuous...

In the flash-lag effect, a flash displayed at the same position as a moving object is perceived to lag the moving object. Current accounts of the illusion make different predictions about how the size of the lag would change if participants compared the position of a moving object to the onset position of a moving probe instead of a flash. We compared the lag effect with a moving probe relative to a flashed probe at motion onset, during ongoing motion, and at motion offset. At motion onset and offset, the lag effect was larger with a moving than with a flashed probe, but there was no difference during ongoing motion. Our results are best explained by the assumption that abrupt changes are erroneously bound to continuous changes following the occurrence of the abrupt change. Typically, the abrupt onset of the flash is misbound to continuous target motion, resulting in the flash-lag effect. With moving probes, abrupt changes of the target (onset, offset) may also be misbound to continuous motion of the probe which increases the lag.