Why does the Quiet Eye improve aiming accuracy? Testing a motor preparation hypothesis with brain potential

The purpose of the present study was to determine whether the Quiet Eye (QE) acquired over time is associated with motor preparation processes by using movement-related cortical potentials (MRCPs). Eighteen male, right-handed college students voluntarily participated in this study. Participants performed a dart throw while wearing an eye-tracking system and electrode cap to measure electroencephalogram waveforms (EEG). After performing the dart task, participants were randomly assigned to a Quiet Eye training group (QET) or control training group (CT). Six subjects were excluded due to incomplete electroencephalography (EEG) data. MRCPs were analysed separately within 4 QE categories: High performance score and Long fixation time (HL), High performance score and Short fixation time (HS), Low performance score and Long fixation time (LL), and Low performance score and Short fixation time (LS). Results revealed that although the QET group acquired QE characteristics, MRCPs did not differ between the two groups. Thus, a longer-term experimental design may be necessary to observe EEG changes. Furthermore, QE durations may relate to not only motor programming but also online control.