In the past, to really know you’re in an alpha state of mind, you would need to hook yourself up to a machine used by neuroscience researchers called an EEG (Electroencephalograph). You would have sensors stuck to your head in certain places that accurately measure your brain wave frequencies. Mainly Beta, Alpha, Theta, and Delta. Nowadays advanced technology has made it possible (and affordable) to have your own EEG headband for home use to practice these alpha brain wave techniques.