- Polhemus Fastrak is used to digitize the position of the EEG electrodes and the subject's head shape before putting the electrodes on the cap.
- Participants have a brief training session (6 trials) to get used to the structure of the task. Stimuli in the training session are different from the ones in the task.
**Task**
Two experimental conditions: motor verbs vs non-motor verbs.
Experiment is broken up into four blocks of 66 trials after which participants are offered a break.
Each participant sees all the 66 stimuli (33 motor and 33 non-motor verbs) repeated 4 times (i.e. the 4 blocks).
Each trial starts with a fixation cross for the duration of 200 ms. Then, a verb (imperative form) appears at the centre of the screen for 200 ms, after a SOA of 1500 ms. ISI duration is 1500 ms.
To assure that participants pay attention to the meaning of stimuli, a definition is shown 25% of the times in a randomised fashion.
Participants are instructed to pay attention to the meaning of each stimulus, as a definition can unpredictably appear from time to time, and they are asked to judge if it's correct or incorrect for the previously presented verb. Response is given by pressing the ‘z’ or ‘m’ button on the keyboard.
Response keys are counterbalanced between participants (‘z’ to answer “correct” and ‘m’ to answer “incorrect” for half of the participants, and vice versa for the other half of them). Definitions are half correct and half incorrect. The stimuli that have to be followed by a definition (25%) are randomly chosen each time for each participant.
Stimulus and definition presentations are always randomised for each list repetition and for each participant in order to properly counterbalance the study.
