Information Processing in Taxis of Physarum Plasmodium. Self-Organization of Size Invariant Positional Information.

It is assumed that positional information within a developing organism is represented by a morphogen gradient. However, it is not yet understood how positional information is organized in a size invariant manner. To achieve such size invariance, it is necessary for an organism to organize the polarity of positional information in advance. We focus on tactic behavior of the Physarum plasmodium and propose a model that describes the organization of size invariant positional information, in which the direction of the phase wave represents the polarity. We would like to point out that self-referential dynamics exist in our model, and their implementation is discussed. Our mode may be applied to other developmental systems.