We wished in this present study, to describe and automate the identification of the strategies implemented by blindfolded subjects. we had resource to the transformation of Fourier in our description. The transform of Fourier is known by his historical relevance in the characterization of the rhythmic behaviour. The trajectories of the subjects are recorded by means of substitution tactile interface. We could define descriptors that differentiate the perceptive strategies. deployed by the subjects. This study has goal to facilitate the acquistion of sensory substitution device. by offering to the subjects rules and strategies which they can adopt. thus they reduce the period of training phase.

This study reveals that when human subjects use an “enactive interface” to perceive graphic forms, they employ a variety of perceptive strategies. The aim of the present paper is to introduce the question of the significance of the enaction concept in perceptive strategies of graphic forms.

“Enactive knowledge” is distributed across all the interactions between an organism and its environment. When a human subject interacts with a computerized virtual environment, his motor acts determine sensory feedback from the machine, giving rise to sensory-motor dynamics. The traces of these interactions, which are readily retrieved from the computer, complete information concerning the user’s activities. The analysis of traces makes it possible to describe the sensory-motor dynamics, and to characterize the variety of strategies employed by the users.

Minimalism is a useful element in the constructivist arsenal against objectivism. By reducing actions and sensory feedback to a bare minimum, it becomes possible to obtain a complete description of the sensory-motor dynamics; and this in turn reveals that the object of perception does not pre-exist in itself, but is actually constituted during the process of observation. In this paper, this minimalist approach is deployed for the case of the recognition of “the Other.” It is shown that the perception of another intentional subject is based on properties that are intrinsic to the joint perceptual activity itself.

Key words: sensory-motor, dynamics, perception, minimalism

This article revisits the concept of autopoiesis and examines its relation to cognition and life. We present a mathematical model of a 3D tesselation automaton, considered as a minimal example of autopoiesis. This leads us to a thesis T1: “An autopoietic system can be described as a random dynamical system, which is defined only within its organized autopoietic domain.” We propose a modified definition of autopoiesis: “An autopoietic system is a network of processes that produces the components that reproduce the network, and that also regulates the boundary conditions necessary for its ongoing existence as a network.” We also propose a definition of cognition: “A system is cognitive if and only if sensory inputs serve to trigger actions in a specific way, so as to satisfy a viability constraint.” It follows from these definitions that the concepts of autopoiesis and cognition, although deeply related in their connection with the regulation of the boundary conditions of the system, are not immediately identical: a system can be autopoietic without being cognitive, and cognitive without being autopoietic. Finally, we propose a thesis T2: “A system that is both autopoietic and cognitive is a living system.”

Key words: Autopoiesis, cognition, life, tessela- tion automaton, random dynamical system, boundary conditions

The following basic question is studied here: In the relatively stable molecular environment of a vertebrate body, can a dynamic idiotypic immune network develop a natural tolerance to endogenous components? The approach is based on stability analyses and computer simulation using a model that takes into account the dynamics of two agents of the immune system, namely B-lymphocytes and antibodies. The study investigates the behavior of simple immune networks in interaction with an antigen whose concentration is held constant as a function of the symmetry properties of the connectivity matrix of the network. Current idiotypic network models typically become unstable in the presence of this type of antigen. It is shown that idiotypic networks of a particular connectivity show tolerance towards auto-antigen without the need for ad hoc mechanisms that prevent an immune response. These tolerant network structures are characterized by aperiodic behavior in the absence of auto-antigen. When coupled to an auto-antigen, the chaotic attractor degenerates into one of several periodic ones, and at least one of them is stable. The connectivity structure needed for this behavior allows the system to adopt particular dynamic concentration patterns which do not lead to an unbounded immune response. Possible implications for the understanding of autoimmune disease and its treatment are discussed.

In this paper we present a new model for the mechanism underlying what is traditionally known in immunology as the “selfnonself” distinction. It turns out that in operational terms, the distinction effected by this model of the immune system is between a sufficiently numerous set of antigens present from the start of the ontogeny of the system on the one hand, and isolated antigens first introduced after the system has reached maturity on the other. The coincidence between this “founder versus late” distinction and the traditional “somatic self-foreign pathogen” one is essentially contingent, an example of the purely opportunistic tinkering characteristic of biological organization in general. We conclude that the so-called “self-nonself” distinction in immunology is a misleading misnomer. This raises the question as to what would genuinely count as a “self-nonself” distinction, a fundamental question for biology in general and Artificial Life in particular.