A method and system for gastric stimulation and imaging for a user. The system having an array of millimeter-sized gastric seeds implanted in a stomach area of a user. Each gastric seed is ultrasonically powered and communicates using a transducer, and the transducer has a recorder to measure a bioelectrical activity in the stomach area of the user. A wearable unit (WU) is worn or carried by the user, and the WU wirelessly powers the gastric seeds. The WU wirelessly communicates with the gastric seeds, and the gastric seeds communicate a parameter to the WU based on the bioelectrical activity. Received pulses by the seeds can be used to localize the position of the seeds and guide the wireless power/data transmission in a self-image-guided manner. A processing unit (PU) wirelessly communicates with the WU, and the WU communicates the parameters from the gastric seeds to the PU.