Medical and biological engineering

, Volume 12, Issue 6, pp 750–758 | Cite as

A mathematical model of the slow-wave electrical activity of the human small intestine

  • B. Robertson-Dunn
  • D. A. Linkens
Article

Abstract

Based on available data of the slow-wave electrical activity in the small intestine of humans and dogs, a mathematical model has been developed. The model comprises an interconnected chain of 100 Van der Pol relaxation oscillators with the method of coupling and its magnitude chosen so that known phenomena in the small intestine are reproduced by the mathematical model. Results from digital simulations on an ICL 1907 computer are presented which show how the model matches the data from the small intestine. Further phenomena such as a travelling area of reduced frequency along the oscillator chain have also been found, and it is shown that this effect is related to the phase relationships along the chain.

Keywords

Electrical activity of the human small intestine 

Sommaire

On a mis au point un modèle mathématique fondé sur les données disponibles d'activité électrique à onde lente dans l'intestin grêle de l'homme et du chien. Ce modèle comporte une chaîne interconnectée de 100 oscillateurs à relaxation Van der Pol dont le mode d'accouplement et la grandeur sont choisis de façon que les phénomènes connus dans l'intestin grêle soient reproduits par le modèle mathématique. On a présenté sur un ordinateur ICL 1907 des résultats provenant de simulations numériques démontrant comment le modèle correspond aux données provenant de l'intestin grêle. On a également découvert d'autres phénomènes tels que: zone de propagation de fréquence réduite le long de la chaîne d'oscillateurs et il est démontré que cet effet est lié aux relations de phase le long de la chaîne.

Zusammenfassung

Ein mathematisches Modell wurde auf Grund der verfügbaren Daten über die elektrische Tätigkeit mit niedriger Phasengeschwindigkeit im Dünndarm des Menschen und von Hunden entwickelt. Das Modell besteht aus einer durch Kupplung verbundenen Kette von 100 Kippgeneratoren vom Typ Van der Pol. Die Größenordnung wurde so gewählt, daß bekannte Phänomene im Dünndarm durch das mathematische Modell dargestellt werden können. Die Ergebnisse aus digitalen Simulierungen mittels eines Rechners vom Typ ICL 1907 sind dargestellt und zeigen, wie das Modell die Daten von dem Dünndarm anpaßt. Weitere Phänomene, z.B. Wanderbereicht der geminderten Frequenz über die Oszillatorkette, wurden ebenfalls festgestellt, und es wird gezeigt, daß diese Wirkung mit den Phasenverhältnissen entlang der Kette verwandt ist.

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Copyright information

© International Federation for Medical & Biological Engineering 1974

Authors and Affiliations

  • B. Robertson-Dunn
    • 1
  • D. A. Linkens
    • 1
  1. 1.Department of Control EngineeringUniversity of SheffieldSheffieldEngland

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