In an open-abdominal anesthetized and fasted canine model of the intact small intestine, the presence, location, shape and frequency of spikes patches were investigated. Recordings were performed with a 240-electrode array (24x10, 2 mm inter electrode distance) from several sites sequentially, spanning the whole length of the small intestine. All 240 electrograms were recorded simultaneously during periods of 5 minutes and were analyzed to reconstruct the origin and propagation of individual spikes. At every level in the small intestine, spikes propagated in all directions before stopping abruptly, thereby activating a circumscribed area termed a 'patch'. Two types of spikes were found; longitudinal spikes, that propagated predominantly in the longitudinal direction and occurred most often in the duodenum. A second type, circumferential spikes, propagated predominantly in the circular direction and occurred much more frequently in the jejunum and ileum. Circumferential spikes conducted faster than longitudinal spikes (17±6 and 7±2 cm/sec respectively; p<0.001). Circumferential spikes originated in > 90% of all cases from the anti-mesenteric border whereas longitudinal spikes were initiated all around the circumference of the intestinal tube. Finally, the spatial sequence of spike patches following the slow wave was very irregular in the upper part of the intestine but much more regular in the lower part. In conclusion, spikes and spike patches occur throughout the small intestine while their type, sites of origin, extent of propagation and frequencies of occurrence differ along the length of the small intestine suggesting differences in the local patterns of motility.