1,072 research outputs found

    Open-ended Search through Minimal Criterion Coevolution

    Get PDF
    Search processes guided by objectives are ubiquitous in machine learning. They iteratively reward artifacts based on their proximity to an optimization target, and terminate upon solution space convergence. Some recent studies take a different approach, capitalizing on the disconnect between mainstream methods in artificial intelligence and the field\u27s biological inspirations. Natural evolution has an unparalleled propensity for generating well-adapted artifacts, but these artifacts are decidedly non-convergent. This new class of non-objective algorithms induce a divergent search by rewarding solutions according to their novelty with respect to prior discoveries. While the diversity of resulting innovations exhibit marked parallels to natural evolution, the methods by which search is driven remain unnatural. In particular, nature has no need to characterize and enforce novelty; rather, it is guided by a single, simple constraint: survive long enough to reproduce. The key insight is that such a constraint, called the minimal criterion, can be harnessed in a coevolutionary context where two populations interact, finding novel ways to satisfy their reproductive constraint with respect to each other. Among the contributions of this dissertation, this approach, called minimal criterion coevolution (MCC), is the primary (1). MCC is initially demonstrated in a maze domain (2) where it evolves increasingly complex mazes and solutions. An enhancement to the initial domain (3) is then introduced, allowing mazes to expand unboundedly and validating MCC\u27s propensity for open-ended discovery. A more natural method of diversity preservation through resource limitation (4) is introduced and shown to maintain population diversity without comparing genetic distance. Finally, MCC is demonstrated in an evolutionary robotics domain (5) where it coevolves increasingly complex bodies with brain controllers to achieve principled locomotion. The overall benefit of these contributions is a novel, general, algorithmic framework for the continual production of open-ended dynamics without the need for a characterization of behavioral novelty

    Evidence for Information Processing in the Brain

    Get PDF
    Many cognitive and neuroscientists attempt to assign biological functions to brain structures. To achieve this end, scientists perform experiments that relate the physical properties of brain structures to organism-level abilities, behaviors, and environmental stimuli. Researchers make use of various measuring instruments and methodological techniques to obtain this kind of relational evidence, ranging from single-unit electrophysiology and optogenetics to whole brain functional MRI. Each experiment is intended to identify brain function. However, seemingly independent of experimental evidence, many cognitive scientists, neuroscientists, and philosophers of science assume that the brain processes information as a scientific fact. In this work we analyze categories of relational evidence and find that although physical features of specific brain areas selectively covary with external stimuli and abilities, and that the brain shows reliable causal organization, there is no direct evidence supporting the claim that information processing is a natural function of the brain. We conclude that the belief in brain information processing adds little to the science of cognitive science and functions primarily as a metaphor for efficient communication of neuroscientific data

    A Practical and Practice-Sensitive Account of Science as Problem-Solving

    Get PDF
    Philosophers of science have recently begun to pay more attention to scientific practice, moving away from the discipline’s focus on theories. The creation of the Society for Philosophy of Science in Practice in 2006, as well as the emergence of scholarship on experimental practice (e.g. Sullivan 2009; 2010; 2016) as well as on the tools scientists use to construct explanations and theories (e.g. Feest 2011) all point to a disciplinary shift towards a more practice-conscious philosophy of science. In addition, scholars are realizing the potential social relevance of philosophy of science and identifying the obstacles that stand in the way of realizing said potential (e.g. Douglas 2010). The aim of this dissertation is to propose a novel descriptive framework for philosophy of science, one that rests on the idea that scientific practice should be described as accurately as possible so that philosophical discussions of science rest on a solid descriptive base and can more easily be of use in engaging users and practitioners of science. The dissertation is organized along the stages of developing what I call the dynamic-iterative model of scientific practice. In chapter 1, I clarify the project’s philosophical background and outline six conditions of adequacy on a descriptive model of science. These conditions allow me to evaluate the three descriptive models reviewed in chapter 2. Chapter 3 combines Nickles’ problem-solving view of science (1981) with core insights from the heuristics and biases literature into a workable version of the dynamic-iterative model. I then apply the model to the case of place cell research in chapter 4 as a test of the model’s usefulness and applicability. In chapter 5 I evaluate the model with respect to my six conditions and assess its strengths and weaknesses. The dynamic-iterative model is a flexible descriptive framework that not only allows for more complete philosophical analyses of cases than other current models, but also supports important practical applications

    CGAMES'2009

    Get PDF

    Ludotopia

    Get PDF
    Where do computer games »happen«? The articles collected in this pioneering volume explore the categories of »space«, »place« and »territory« featuring in most general theories of space to lay the groundwork for the study of spatiality in games. Shifting the focus away from earlier debates on, e.g., the narrative nature of games, this collection proposes, instead, that thorough attention be given to the tension between experienced spaces and narrated places as well as to the mapping of both of these

    Hierarchical control over effortful behavior by rodent medial frontal cortex : a computational model

    Get PDF
    The anterior cingulate cortex (ACC) has been the focus of intense research interest in recent years. Although separate theories relate ACC function variously to conflict monitoring, reward processing, action selection, decision making, and more, damage to the ACC mostly spares performance on tasks that exercise these functions, indicating that they are not in fact unique to the ACC. Further, most theories do not address the most salient consequence of ACC damage: impoverished action generation in the presence of normal motor ability. In this study we develop a computational model of the rodent medial prefrontal cortex that accounts for the behavioral sequelae of ACC damage, unifies many of the cognitive functions attributed to it, and provides a solution to an outstanding question in cognitive control research-how the control system determines and motivates what tasks to perform. The theory derives from recent developments in the formal study of hierarchical control and learning that highlight computational efficiencies afforded when collections of actions are represented based on their conjoint goals. According to this position, the ACC utilizes reward information to select tasks that are then accomplished through top-down control over action selection by the striatum. Computational simulations capture animal lesion data that implicate the medial prefrontal cortex in regulating physical and cognitive effort. Overall, this theory provides a unifying theoretical framework for understanding the ACC in terms of the pivotal role it plays in the hierarchical organization of effortful behavior

    Ludotopia

    Get PDF
    Where do computer games »happen«? The articles collected in this pioneering volume explore the categories of »space«, »place« and »territory« featuring in most general theories of space to lay the groundwork for the study of spatiality in games. Shifting the focus away from earlier debates on, e.g., the narrative nature of games, this collection proposes, instead, that thorough attention be given to the tension between experienced spaces and narrated places as well as to the mapping of both of these

    Analyzing Digital Literacy Demands, Practices, and Discourses within a Library Computer Programming Club for Children

    Get PDF
    abstract: Among researchers, educators, and other stakeholders in literacy education, there has been a growing emphasis on developing literacy pedagogies that are more responsive to the ways young people experience literacy in their everyday lives, which often make use of digital media and other technologies for exchanging meaning. This dissertation project sought to explore the nature of these digital-age literacies in the context of children learning through and about new technologies. Conducting a year-long, multimethod observational study of an out-of-school library-based program designed to engage students in self-directed learning around the domain of computer programming, this project was framed around an analysis of digital-age literacies in design, discourse, and practice. To address each of these areas, the project developed a methodology grounded in interpretive, naturalistic, and participant-observation methodologies in collaboration with a local library Code Club in a metropolitan area of the Southwestern U.S between September 2016 and December 2017. Participants in the project included a total of 47 students aged 8-14, 3 librarians, and 3 parents. Data sources for the project included (1) artifactual data, such as the designed interfaces of the online platforms students regularly engaged with, (2) observational data such as protocol-based field notes taken during and after each Code Club meeting, and (3) interview data, collected during qualitative interviews with students, parents, and library facilitators outside the program. These data sources were analyzed through a multi-method interpretive framework, including the multimodal analysis of digital artifacts, qualitative coding, and discourse analysis. The findings of the project illustrate the multidimensional nature of digital-age literacy experiences as they are rendered “on the screen” at the content level, “behind the screen” at the procedural level, and “beyond the screen” at the contextual level. The project contributes to the literature on literacy education by taking an multi-method, interdisciplinary approach to expand analytical perspectives on digital media and literacy in a digital age, while also providing an empirical account of this approach in a community-embedded context of implementation.Dissertation/ThesisDoctoral Dissertation Learning, Literacies and Technologies 201

    Computational inquiry into navigation with particular reference to the Hippocampus

    Get PDF
    • 

    corecore