Electroencephalograms (EEG): EEG, the "brainwave" test, shows the electrical function of the brain. Electrodes are placed onto the scalp, and a computer captures the tiny electrical signals the brain makes over the course of 30 minutes. There is no discomfort involved in testing. The test takes a total of about 1-1/2 hours. Your doctor may order your test as sleep deprived (no more than 4-5 hours sleep the night before) which is commonly ordered for children. Sleep deprivation actually helps to enhance your test. Please avoid caffeine and stimulants before the test, but eat and take medications as you normally would. Please have clean, dry hair without hairspray or styling gel.