Some rhythmic contraction waves propagated a short distance into the proximal oesophagus.

For one thing, in peristalsis, the speed of blood flow should be equal to the speed at which the contraction wave travels through the walls.

The pacemaker will reverse the contraction wave of your heart and as a result, ease the obstruction caused by the backup of blood."

Also, the normal deglutitive response is generally considered to consist of a contraction wave that appears at manometry as a single or M shaped peak.

The bursts of repetitive, non-sequential pressure peaks were often interrupted by peristaltic contraction waves, which could be deglutitive or non-deglutitive in nature.

The response to bolus distension within the oesophagus is proximal contraction and distal relaxation and the generation of an aboral contraction wave.

In cases where two sponges are fused, for example if there is a large but still unseparated bud, these contraction waves slowly become coordinated in both of the "Siamese twins".

On the other hand, the increase found in the contractile force of the oesophageal body together with an accelerated propagation of the contraction waves may be responsible for the acceleration of acid clearance.

Peristalsis was considered 'failed' either if there was no contraction wave at all, or if it failed to traverse the entire length of the oesophagus, or if a simultaneous contraction occurred.

This study shows that the motor activity of the normal human oesophagus is not limited to contraction waves in response to swallowing, but that non-deglutitive motility patterns occur in almost all normal gullets.

The individual stretches and contractions of the segments are coordinated by the nervous system such that contraction waves run the length of the body, each pair of legs swinging forward and then down and rearward in succession.

Other motor abnormalities of the oesophagus that may contribute to the development of reflux oesophagitis are diminished peristaltic pressure amplitude, shortened duration and slowed propagation of the contraction waves, reduced peristaltic frequency, and delayed oesophageal transit.

Propagation velocity had to be neither more than 8.3 cm/s nor less than 1 cm/s;(8) non-propagated contractions (No/24 h), defined as contraction waves that are not associated with a proximal contraction wave or have an apparent propagation velocity >8.3 cm/s.

By slicing a worm into separate segments, and attaching each segment to a sensitive voltmeter, he noticed distinct, consecutive deflections on the meter which demonstrated a potentional wave moving through the severed parts from the front to the end of the entire cut-up specimen at approximately the speed of a contraction wave of a wriggling earthworm.