Abstract: Gastric apparatus is provided, including one or more sensors, adapted to generate respective sensor signals responsive to activity of a gastrointestinal tract of a subject. A control unit is configured with an eating detection threshold selected from the group consisting of: a predetermined threshold, and a threshold determined during a calibration procedure. The control unit is adapted to receive and analyze the sensor signals, and identify an aspect of at least one of the sensor signals indicative of periodic activity of the gastrointestinal tract. The control unit modifies the eating detection threshold responsive to identifying the aspect of the signals that is indicative of the periodic activity, and determines that an eating event has occurred responsive to the modified eating detection threshold and at least one of the analyzed sensor signals. Other embodiments are also described.

Abstract: A method is provided that includes providing a fundic impedance signal of a subject sensed during an initial calibration period using at least one implantable fundic sensor of an eating detection device. An indication is received of actual ingestion events of the subject during the initial calibration period. Using a cost function, an analysis is performed of the fundic impedance signal and the actual ingestion events. Responsively to the analysis, a threshold is set, the crossing of which by the fundic impedance signal is indicative of ingestion. The threshold is stored in a memory of the eating detection device. Other embodiments are also described.

Abstract: Apparatus (18, 18?) is provided, which includes one or more fundic sensors (74), configured to be applied to a fundus of a subject (10), and to generate a fundic signal. The apparatus further includes a control unit (90), which is configured to make a tentative determination of ingestion by the subject (10), determine fundic impedance responsively to the fundic signal, and calculate a duration of a period during which the fundic impedance rose during the tentatively-determined ingestion. Upon finding that the duration is less than a fundic rise duration threshold value, the control unit (90) determines that the tentative determination of ingestion is a false positive. Other embodiments are also described.

Abstract: Apparatus (18, 18?) is provided, which includes one or more fundic sensors (74), configured to be applied to a fundus of a subject (10), and to generate a fundic signal. The apparatus further includes a control unit (90), which is configured to make a tentative determination of ingestion by the subject (10), determine fundic impedance responsively to the fundic signal, and calculate a duration of a period during which the fundic impedance rose during the tentatively-determined ingestion. Upon finding that the duration is less than a fundic rise duration threshold value, the control unit (90) determines that the tentative determination of ingestion is a false positive. Other embodiments are also described.

Abstract: A method is provided that includes providing a fundic impedance signal of a subject sensed during an initial calibration period using at least one implantable fundic sensor of an eating detection device. An indication is received of actual ingestion events of the subject during the initial calibration period. Using a cost function, an analysis is performed of the fundic impedance signal and the actual ingestion events. Responsively to the analysis, a threshold is set, the crossing of which by the fundic impedance signal is indicative of ingestion. The threshold is stored in a memory of the eating detection device. Other embodiments are also described.

Abstract: Gastric apparatus (18) is provided, including one or more sensors (70, 72, 74), adapted to generate respective sensor signals responsive to activity of a gastrointestinal tract of a subject. A control unit (90) is adapted to receive and analyze the sensor signals and to determine that an eating event has occurred, responsive to at least one of the sensor signals and a threshold. The control unit identifies an aspect of at least one of the sensor signals deriving from rhythmic activity of the gastrointestinal tract that is not indicative of current eating by the subject, and modifies the threshold responsive to the aspect of the signals that derives from activity that is not indicative of current eating. For some applications, the control unit is adapted to modify the threshold if the aspect is indicative of a migrating motor complex (MMC). Other embodiments are also described.