Brain-activated technology. Researchers using brain activity to control a cursor on a computer screen. The subject, trained using biofeedback techniques, is able to alter the pattern of various brain waves. The patterns, a combination of electroencephalogram (EEG) and electromyogram (EMG) signals, are detected by electrodes on the subject's head, and are interpreted by a computer as simple commands such as 'move left' or 'move down'. The subject is then able to negotiate the cursor through a maze on the screen. Photographed at Brain Actuated Technologies Inc, Ohio, USA.