Research staff will record the brain activity of subjects by using an electroencephalogram (EEG), a device that measures the electrical activity in the brain through electrodes put on the scalp. There is no risk of electrical shock. Research staff will put a cap on the subject's head that has electrodes that will measure your brain activity. In addition to the electrodes in the cap, two electrode clips will be put on your ears. EEG activity will be collected for 20 minutes: subjects will have their eyes open for ten minutes, and then eyes closed for ten minutes.