Figure 2.

Serial reaction time task (SRTT). The SRTT is realized by four horizontally aligned bars presented on a screen in front of the participants. The figure exemplifies one of the three sequences applied in the present study. Each bar corresponded to one button of a custom-made response box, which was connected to a standard windows PC. The participants were instructed to respond as fast and as accurately as possible by button press with the right hand as soon as one bar changed its color. Each correct response was followed by a fixed interval of 1000 ms.