In order to enable a user to easily and quickly ascertain his body's state of relaxation, the device is provided with: a physiological information extractor 101 for extracting an indicator expressing physiological state from user Y; a storage member 102 for storing the extracted indicator; a judging...http://www.google.co.uk/patents/US6554763?utm_source=gb-gplus-sharePatent US6554763 - Relaxation guidance device and biofeedback guidance device
