Description: This article focuses on dynamic networking and dynamic networks in complex research on psychophysics, psychology, and neurophysiology. It states that new ways were suggested by dynamic networking and dynamic networks to transfer information utilizing the long-distance communication through local cooperative interaction. It says that the fluctuations in brain and social dynamics reveal the emergence of complex behavior when analyzed with advanced methods of fractal statistical analysis.

Description: This article includes discussions from self-organized to extended criticality. Abstract: We address the issue of criticality that is attracting the attention of an increasing number of neurophysiologists. Our main purpose is to establish the specific nature of some dynamical processes that although physically different, are usually termed as "critical," and we focus on those characterized by the cooperative interaction of many units. We notice that the term "criticality" has been adopted to denote both noise-induced phase transitions and Self-Organized Criticality (SOC) with no clear connection with the traditional phase transitions, namely the transformation of a thermodynamic system from one state of matter to another. We notice the recent attractive proposal of extended criticality advocated by Bailly and Longo, which is realized through a wide set of critical points rather than emerging as a singularity from a unique value of the control parameter. We study a set of cooperatively firing neurons and we show that for an extended set of interaction couplings the system exhibits a form of temporal complexity similar to that emerging at criticality from ordinary phase transitions. This extended criticality regime is characterized by three main properties: (i) In the ideal limiting case of infinitely large time period, ...

Description: This article discusses criticality and transmission of information in a swarm of cooperative units. Abstract: We show that the intelligence of a swarm of cooperative units (birds) emerges at criticality, as an effect of the joint action of frequent organizational collapses and of spatial correlation as extended as the flock size. The organizational collapses make the birds become independent of one another, thereby allowing the flock to follow the direction of the lookout birds. Long-range correlation violates the principle of locality, making the lookout birds transmit information on either danger or resources with a time delay determined by the time distance between two consecutive collapses.

Description: In this article, the authors study the transport of information between two complex systems with similar properties. Both systems generate non-Poisson renewal fluctuations with a power-law spectrum 1/f 3-μ, the case μ=2 corresponding to ideal 1/f noise. The authors denote by μs and μp the power-law indexes of the system of interest S and the perturbing system P, respectively. By adopting a generalized fluctuation-dissipation theorem (FDT) the authors show that the ideal condition of 1/f noise for both systems corresponds to maximal information transport. The authors prove that to make the system S respond when μs < 2 the authors have to set the condition μp < 2. In the latter case, if μp < μs, the system S inherits the relaxation properties of the perturbing system. In the case where μp > 2, no response and no information transmission occurs in the long-time limit. The authors consider two possible generalizations of the fluctuation dissipation theorem and show that both lead to maximal information transport in the condition of 1/f noise.

Description: This is a Publisher's Note for the article 'Beyond the Death of Linear Response: 1/f Optimal Information Transport' [Phys. Rev. Lett. 105, 040601 (2010)].