Abstract: The invention provides a method and apparatus for automatically detecting loss of normal gastric myoelectrical activity and certain gastric dysrhythmias which indicate an imminent onset of nausea. Analog signals indicative of gastric myoelectrical activity are detected via electrodes, conditioned and then digitized. The resulting digital signals are passed through a digital band pass filter which has a pass band with a lower limit set at or near zero Hz, and the digitally conditioned signals are compared in a digital computer with stored predetermined signal patterns that are known to be indicative of the onset of imminent nausea. Upon detection of a match, an alarm is activated.