AIBO’s first words

This paper explores the hypothesis that language communication in its very first stage is bootstrapped in a social learning process under the strong influence of culture. A concrete framework for social learning has been developed based on the notion of a language game. Autonomous robots have been programmed to behave according to this framework. We show experiments that demonstrate why there has to be a causal role of language on category acquisition; partly by showing that it leads effectively to the bootstrapping of communication and partly by showing that other forms of learning do not generate categories usable in communication or make information assumptions which cannot be satisfied.

Do facial structural characteristics communicate information about health?

High levels of sex hormones may lower immunocompetence, making it difficult for a person’s body to fight off infections. Facial characteristics that reveal high levels of sex hormones might signal the presence of a robust immune system. In men, high testosterone levels are associated with prominent cheekbones, wide jaw, and long chin. In women, high estrogen levels are associated with prominent cheekbones, narrow jaw, and short chin. We examined whether facial features associated with immunocompetence positively covary with health. Participants from 2 groups of university students (67 women, 34 men, in total) completed daily measures of psychological, emotional, and physical health over a one-month period. Physiological fitness was assessed via cardiac recovery time following exercise. A facial photograph of each participant was rated along several personality dimensions, activity level, and attractiveness. Using the photographs, we measured participants’ jaw width, chin length, and cheekbone prominence. Results provide unimpressive evidence for the hypotheses that (1) women displaying an estrogenized face and (2) men displaying a testosteronized face are physiologically, psychologically, and emotionally healthier. Discussion highlights directions for future work on whether facial structural characteristics might communicate information about underlying health.

Meaning = Life (+ Culture)

The article presents the outlines of an integrative theory of meaning based on the concept of value, understood both as a biological and as a socio-cultural category, synthesizing ideas from evolutionary and developmental psychology, semiotics and cybernetics. The proposal distinguishes between four types of meaning systems, cue-based, associational, mimetic and symbolic, forming an evolutionary and epigenetic hierarchy. The theory is applied to phylogenetic and human ontogenetic development, pointing out significant parallels between the two processes, involving both continuity and discontinuity between the different levels. Since one of the basic tenets of the theory is that only living systems have intrinsic value, which is a necessary and sufficient condition for possessing the category meaning, negative implications are drawn for the meaning potential of (current) artificial systems.

Acoustic structure and contexts of emission of vocal signals by black lemurs

We investigated the vocal repertoire of a Malagasy primate: the black lemur (Eulemur macaco macaco). The first study allowed the characterization of 16 different vocal signals on the basis of acoustic parameters. Black lemurs emit sparse harmonic sounds, dense harmonic sounds, spectrally structured noise (Beeman, 1998) and a wide variety of grunts. The second study focused on the behavioral context of emission of these signals and used the pre- and post-event histogram method (Douglass and Sudd, 1980; Preuschoft, 1995a). It provides statistical demonstration of the association between a signal and other behaviors of the emitter, thus giving insight into the latter’s motivations. Four signals are linked to affiliative and agonistic interactions. Three signals express a state of alarm, and two appear related to discomfort. Most grunts are linked to contact and signal precisely the emitter’s level of vigilance. Other interdisciplinary communication studies could benefit from methodology and software used here.

Bootstrapping grounded symbols by minimal autonomous robots

In this paper an experiment is presented in which two mobile robots develop a shared lexicon of which the meanings are grounded in the real world. The robots start without a lexicon nor shared meanings and play language games in which they generate new meanings and negotiate words for these meanings. The experiment tries to find the minimal conditions under which verbal communication may begin to evolve. The robots are autonomous in terms of computing and cognition, but they are otherwise far simpler than most, if not all animals. It is demonstrated that a lexicon nevertheless can be made to emerge even though there are strong limits on the size and stability of this lexicon.