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168 Chapter 7 daily transanal colonic irrigation, n = 3). It should be noted that these treatments were not solely based on the manometry results; however, the manometry did guide our decision making. Long-single motor pattern Long-single propagating motor patterns travel rapidly in an antegrade direction across all of the recording sites that span the descending and sigmoid colon (in healthy, they originate in the proximal colon 17 ). The specific physiological role of this motor pattern is unknown. However, given the low amplitude of the component pressure events and its speed of propagation, it would be unlikely to propel solid content through the colon. This motor pattern was more prevalent in the children than either of the adult groups and the question arises as to why this occurred. Although the pressure events that make up these motor patterns cannot be distinguished by shape from those that make up the cyclic motor patterns, it is possible that they are due to intrinsic neural activity. 17 There is increasing evidence that within the small intestine and in the colonofmostmammalian species studied, in addition to the content-dependent propulsive peristaltic contractions (corresponding to the HAPS in humans), there are enteric circuits that generate spontaneous cyclic motor activity at intervals of about a minute. These have been variably described as discrete clustered contractions in the small intestine 35,36 or colonic migrating motor complexes. 28,37,38 They appear to occur even in the empty mouse colon. 39 There are relatively few studies of isolated preparations of human colon that address this question. In short isolated segments of normal colon regular large phasic slow contractions at minute intervals have been recorded which are insensitive to neural blockade (thus appear to be myogenic). 40 Interestingly, the authors of that work found that these myogenic slow contractions could be triggered and reset by intrinsic neural inputs, indicating the modulating role of neural inputs on myogenic activity. Also of relevance is the observation that in isolated long segments of human colon studied ex vivo , similar minute pattern of phasic contractions was recorded over long distances 41 resembling the long-single propagating motor pattern observed in some of our children. While this long-singlemotor pattern is present in healthy adults 17 and adultswith slow-transit constipation 13 , it only occurs in low numbers. This motor patterns becomes apparent when whole sections of human colon are studied in an organ bath; we, therefore, hypothesize that this motor pattern is normally suppressed in vivo . 41 The most likely explanation for this is that the motor pattern is subject to ongoing enteric inhibitory inputs. Therefore, abnormally decreased extrinsic neural activity may see these motor patterns revealed, and this may