Investigation of Intestinal Slow waves, Spike Bursts, and Motility

<p><b>Supplementary Video 1:</b> A free-form deformation mesh fitted to a spontaneous peristaltic contraction in a pig intestine. The mesh is colour-coded according to the transverse strain fields. As the intestine contracts, the mesh also deforms, and the negative strain indicates the contracted region.</p> <p> </p> <p><b>Supplementary Video 2:</b> A free-form deformation mesh fitted to cyclic peristaltic contractions in a rabbit intestine. The mesh is colour-coded according to the transverse strain fields. These peristaltic contractions propagated along the intestine in a regular manner. The mesh deforms with the peristaltic contractions and the deforming mesh was used to calculate the strain fields.</p> <p> </p> <p><b>Supplementary Video 3: </b>Slow wave and spike burst activity during segmental contractions in pig. Slow waves are shown in red and spike bursts are shown in blue. As the intestine contracts, the mesh also deforms, and the negative strain indicates the contracted regions.<b></b></p> <p> </p> <p><b>Supplementary Video 4: </b>Slow wave and spike burst activity during spontaneous peristaltic contractions in pig. Slow waves are shown in red and spike bursts are shown in blue. These peristaltic contractions originated spontaneously and propagated short distances. The spontaneous peristaltic contractions were underpinned by propagating circumferential spike burst patches, which occurred independently to the slow wave activity.</p> <p> </p> <p><b>Supplementary Video 5: </b>Slow wave and spike burst activity during cyclic peristaltic contractions in rabbit. Slow waves are shown in red and spike bursts are shown in blue. Cyclic peristaltic contractions originated and propagated along the intestine in a regular manner. These peristaltic contractions were also underpinned by propagating circumferential spike burst patches. However, the spike bursts occurred regularly with the slow wave cycles.</p> <p> </p> <p><b>Supplementary Video 6:</b> Slow wave and spike burst activity during pendular contractions in pig. Slow waves are shown in red and spike bursts are shown in blue. Longitudinal pendular contractions were caused by longitudinal spike burst patches. These spike bursts occurred with the slow wave cycles. The longitudinal contractions in the mesenteric and anti-mesenteric borders were different, which was due to different spike burst activation patterns at the corresponding borders.</p> <p> </p> <p><b>Supplementary Video 7:</b> Bioelectrical and contractile activity of the intestine during baseline, ischemia, and reperfusion. Slow waves are shown in red and spike bursts are shown in blue. During baseline, the intestine was quiescent, and slow waves propagated throughout the segment. During ischemia, the intestine went into a spasm of circumferential contractions mediated by an increase in spike bursts activating as circumferential patches. The slow waves became sporadic in the ischemic region, and the ischemic region acted as a conduction block to the slow waves propagating from the surrounding regions. During reperfusion, slow waves regain the normal periodic nature and propagated throughout the previously ischemic segment. The spike bursts died down, and the contractions subsided.</p>