Fractals in the Nervous System: conceptual Implications for Theoretical Neuroscience

This essay is presented with two principal objectives in mind: first, to document the prevalence of fractals at all levels of the nervous system, giving credence to the notion of their functional relevance; and second, to draw attention to the as yet still unresolved issues of the detailed relationships among power law scaling, self-similarity, and self-organized criticality. As regards criticality, I will document that it has become a pivotal reference point in Neurodynamics. Furthermore, I will emphasize the not yet fully appreciated significance of allometric control processes. For dynamic fractals, I will assemble reasons for attributing to them the capacity to adapt task execution to contextual changes across a range of scales. The final Section consists of general reflections on the implications of the reviewed data, and identifies what appear to be issues of fundamental importance for future research in the rapidly evolving topic of this review

Simulated Experince Evaluation in Developing Multi-agent Coordination Graphs

Cognitive science has proposed that a way people learn is through self-critiquing by generating \u27what-if\u27 strategies for events (simulation). It is theorized that people use this method to learn something new as well as to learn more quickly. This research adds this concept to a graph-based genetic program. Memories are recorded during fitness assessment and retained in a global memory bank based on the magnitude of change in the agent’s energy and age of the memory. Between generations, candidate agents perform in simulations of the stored memories. Candidates that perform similarly to good memories and differently from bad memories are more likely to be included in the next generation. The simulation-informed genetic program is evaluated in two domains: sequence matching and Robocode. Results indicate the algorithm does not perform equally in all environments. In sequence matching, experiential evaluation fails to perform better than the control. However, in Robocode, the experiential evaluation method initially outperforms the control then stagnates and often regresses. This is likely an indication that the algorithm is over-learning a single solution rather than adapting to the environment and that learning through simulation includes a satisficing component

Language: The missing selection pressure

Human beings are talkative. What advantage did their ancestors find in communicating so much? Numerous authors consider this advantage to be "obvious" and "enormous". If so, the problem of the evolutionary emergence of language amounts to explaining why none of the other primate species evolved anything even remotely similar to language. What I propose here is to reverse the picture. On closer examination, language resembles a losing strategy. Competing for providing other individuals with information, sometimes striving to be heard, makes apparently no sense within a Darwinian framework. At face value, language as we can observe it should never have existed or should have been counter-selected. In other words, the selection pressure that led to language is still missing. The solution I propose consists in regarding language as a social signaling device that developed in a context of generalized insecurity that is unique to our species. By talking, individuals advertise their alertness and their ability to get informed. This hypothesis is shown to be compatible with many characteristics of language that otherwise are left unexplained.Comment: 34 pages, 3 figure

Extending digital infrastructures : a typology of growth tactics

Digital infrastructures enable delivery of information services in functional areas such as health, payment, and transportation by providing a socio-technical foundation for partnership governance, resource reuse, and system integration. To effectively serve new purposes and emerging possibilities, however, a key question concerns how an infrastructure can be extended to cater for future services in its functional area? In this paper, we approach such digital infrastructure growth as a challenge related to the alignment of new partners whose capabilities spur innovative services that attract more users. We advance an initial typology that covers four growth tactics (i.e., adding services, inventing processes, opening identifiers, and providing interfaces) with potential to set extension of infrastructures in motion. We then explore the proposed typology by investigating the ways in which its particular tactics successfully extended the scope of a digital infrastructure for public transportation. Our insights invite IS scholars to engage more deeply in the development of growth tactics, which achieve infrastructure extensions that make service delivery durable

Extending Digital Infrastructures: A Typology of Growth Tactics

Digital infrastructures enable delivery of information services in functional areas such as health, payment, and transportation by providing a sociotechnical foundation for partnership governance, resource reuse, and system integration. To effectively serve emerging possibilities and changing purposes, however, a key question concerns how an infrastructure can be extended to cater for future services in its functional area. In this paper, we approach such digital infrastructure growth as a challenge of aligning new partners whose digital capabilities spur innovative services that attract more users. We advance an initial typology that covers four growth tactics (i.e., adding services, inventing processes, opening identifiers, and providing interfaces) with the potential to set extension of infrastructures in motion. We then explore the proposed typology by investigating the ways in which its particular tactics successfully extended the scope of a digital infrastructure for public transportation in Stockholm, Sweden. Our insights invite IS scholars to engage more deeply in the development of growth tactics that achieve infrastructure extensions necessary for improving the durability of service delivery