A standard visual oddball experiment, implemented on the E-prime software system (Psychology Software Tools Inc., Pittsburgh, USA), was utilized for the EEG recordings. The task consisted of the presentation of three types of visual stimuli, these being standard non-target stimuli (N = 210), rare non-target stimuli (N = 35) and target stimuli (N = 35). The subjects were instructed not to respond to the standard and rare non-target stimuli, and to press a response box button as quickly as possible when presented with a target stimulus.
