Figure 1

Trial structure. Each trial began with a fixation cross (jittered time between 500 and 800 ms) followed by the presentation of a search array (max 1500 ms). Participants were instructed to search for a target stimulus (rotated T) and to report its rotation by pressing “-” (target rotated counterclockwise) or “z” (target rotated clockwise) keys on the keyboard. Each response was followed by an auditory feedback (200 ms) that varied based on participants’ response (i.e., hit: 800 Hz; incorrect: 200 Hz; miss: 500 Hz). The search array disappeared whenever a response was provided and was followed by a variable duration blank black screen ensuring a constant trial duration regardless of individual response speed. Search arrays could be either “new” or “old”. In new arrays, stimuli were randomly displaced on the monitor, while old arrays consisted in the presentation of pre-determined arrangements of stimuli. Each new search array was presented once in the entire experiment, while each old search array was repeated once in each block. Each block consisted in the presentation of 24 trials (12 new and 12 old) and the whole experiment comprised of 13 blocks.