Rare footage of Timothy Leary in early 1990s exploring an 'IBVA' brainwave monitor ( worn on the back of his head ) measuring his EEG via electrodes inside the blue headband across his forehead. The sounds are triggered by changes in his concentration as he interrogates the system on an Apple computer. IBVA is a portable brainwave monitor supplied internationally by IBVA UK ; for more information please visit www.ibva.co.uk Less