 - Participants will attend the department of clinical neurophysiology and a member of the research team will take consent. Two experienced EEG technicians will place the electrodes and explain the procedure. We will record resting state EEG. Participants will be told to lie still with eyes closed. It will be explained that although their eyes are closed they must remain awake. Participants will be continuously monitored and if they become drowsy will be re-stimulated and the time of drowsiness will be recorded. This instruction and monitoring is the same as that used in previous EEG and fMRI studies looking at resting state paradigms. 